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BACnet Application Guidefor Consulting Engineers

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BACnet® Application Guide for Consulting Engineers125-1984T Rev. 1, January, 2012

Rev. 1, January, 2012

NOTICE

The information contained within this document is subject to change without notice and should not be construed as a commitment by Siemens Building Technologies, Inc. Siemens Building Technologies, Inc. assumes no responsibility for any errors that may appear in this document.

All software described in this document is furnished under a license and may be used or copied only in accordance with the terms of such license.

WARNING

This equipment generates, uses, and can radiate radio frequency energy and if not installed and used in accordance with the instructions manual, may cause interference to radio communications. It has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equipment in a residential area is likely to cause interference in which case users at their own expense will be required to take whatever measures may be required to correct the interference.

SERVICE STATEMENT

Control devices are combined to make a system. Each control device is mechanical in nature and all mechanical components must be regularly serviced to optimize their operation. All Siemens Building Technologies, Inc.branch offices and authorized distributors offer Technical Support Programs that will ensure your continuous, trouble-free system performance.

For further information, contact your nearest Siemens Building Technologies, Inc. representative.

Copyright 2007 by Siemens Building Technologies, Inc.

TO THE READER

Your feedback is important to us. If you have comments about this manual, please submit them to: [email protected]

APOGEE is a registered trademark of Siemens Building Technologies, Inc. Tracer Summit is a trademark of The Trane Company BACnet is a registered trademark of American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) Insight for Minicomputers is a registered trademark of Siemens Building Technologies, Inc. Insight for Personal Computers is a registered trademark of Siemens Building Technologies, Inc. Country of Origin: US

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Table of Contents

About this Application Guide ........................................................................................................ I

Purpose of this Guide .................................................................................................................. I

How this Guide is Organized ....................................................................................................... I

Suggested Reference Materials ................................................................................................. II

Symbols ...................................................................................................................................... II

Getting Help ............................................................................................................................... III

Where to Send Comments ........................................................................................................ III

Chapter 1–Introduction to BACnet............................................................................................... 1

What is BACnet?......................................................................................................................... 1

Why BACnet was Developed...................................................................................................... 2

How BACnet was Developed...................................................................................................... 3

Certification ................................................................................................................................. 3

BACnet Implementation within APOGEE ................................................................................... 3

Chapter 2–BACnet Objects and Services.................................................................................... 5

Objects Theory............................................................................................................................ 5

Properties of Objects................................................................................................................ 6 The OBJECT_TYPE Property ............................................................................................... 7 Command Priority Properties ................................................................................................ 8

BACnet Device ....................................................................................................................... 14 Point-Like Objects .................................................................................................................. 16

Analog Input Object ............................................................................................................. 16 Analog Output Object .......................................................................................................... 18 Analog Value Object ............................................................................................................ 19 Binary Input Object .............................................................................................................. 20 Binary Output Object ........................................................................................................... 21 Binary Value Object ............................................................................................................. 23 Multi-State Input Object ....................................................................................................... 24 Multi-State Output Object .................................................................................................... 24 Multi-State Value Object...................................................................................................... 25

Other Objects Supported by APOGEE BACnet Field Panels................................................ 26 Calendar Object................................................................................................................... 26 Command Object................................................................................................................. 27 File Object............................................................................................................................ 27 Notification Class Object ..................................................................................................... 27

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Schedule Object .................................................................................................................. 27 Trend Log Object ................................................................................................................. 27

Viewing with the BACnet Browser.......................................................................................... 27 Services Theory ........................................................................................................................ 29

Services Supported................................................................................................................ 31 Services Not Supported ......................................................................................................... 32

Chapter 3–BACnet Interoperability ............................................................................................ 33

Interoperability .......................................................................................................................... 33

Certification ............................................................................................................................ 34 Specifying BACnet ................................................................................................................. 34

Protocol Implementation and Conformance Statement....................................................... 35 BACnet Interoperable Building Blocks................................................................................. 37

BACnet Device Profiles.......................................................................................................... 41 Building Controller Profile (B-BC) and Operator Workstation Profile (B-OWS)................... 42

Chapter 4–BACnet Communications......................................................................................... 45

BACnet Networking Technologies ............................................................................................ 45

Master-Slave/Token-Passing ................................................................................................. 45 LonTalk Cautions ................................................................................................................... 46 BACnet Protocol Model .......................................................................................................... 46 Basic BACnet Networking ...................................................................................................... 47

Native BACnet Devices On The Same LAN........................................................................ 47 Native BACnet Devices with Different LAN Technologies................................................... 48 Native BACnet to Non-Native BACnet Devices................................................................... 49

BACnet Communications ....................................................................................................... 50 BACnet/IP ............................................................................................................................ 50 BACnet Broadcast Management Device (BBMD) ............................................................... 51 BACnet Foreign Devices ..................................................................................................... 53 BACnet Router vs. IP Router............................................................................................... 54

Chapter 5–BACnet Field Panel ................................................................................................... 55

APOGEE BACnet Field Panel .................................................................................................. 55

Field Panel Hardware............................................................................................................. 55 Field Panel Features .............................................................................................................. 55 BTL Certification..................................................................................................................... 56

Chapter 6–Insight BACnet Option.............................................................................................. 57

Insight BACnet Option .............................................................................................................. 57

Native BACnet and B-OWS ................................................................................................... 57 Backward Compatibility .......................................................................................................... 58

Insight Changes for BACnet ..................................................................................................... 58

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BACnet Alarms....................................................................................................................... 58 Point Priority ........................................................................................................................ 58 Initials................................................................................................................................... 58 Alarm Acks........................................................................................................................... 58 Event Information and Alarm Summary............................................................................... 59 Unknown BACnet alarms .................................................................................................... 59 BACnet Text Messages....................................................................................................... 59 Alarm Priority ....................................................................................................................... 60 Alarm Messages .................................................................................................................. 60

APOGEE GO.......................................................................................................................... 60 Attribute Duplicator................................................................................................................. 61 BACNET Object Browser ....................................................................................................... 61

BACnet Browser Features................................................................................................... 62 BACnet Browser Limitations................................................................................................ 63

Point Commander .................................................................................................................. 63 Database Transfer.................................................................................................................. 66

Progress Tab ....................................................................................................................... 66 Log Tab................................................................................................................................ 66 Upload Selected Dialog ....................................................................................................... 67 Object Types........................................................................................................................ 67 Backup and Restore ............................................................................................................ 67

Other Changes ....................................................................................................................... 68 Dynamic Plotter ...................................................................................................................... 68 Event Log ............................................................................................................................... 68 Event Printer........................................................................................................................... 68

RENO Notification................................................................................................................ 68 PXC Compact Slope/Intercept............................................................................................. 68

Program Editor ....................................................................................................................... 68 Report Builder/Reports........................................................................................................... 69

Display BACnet Priority ....................................................................................................... 69 Reports................................................................................................................................... 69

Point Definition Report......................................................................................................... 69 Panel Point Definition Report .............................................................................................. 69 Panel Configuration Report ................................................................................................. 69 Panel Display Report ........................................................................................................... 70 User Account Report ........................................................................................................... 70 System Profile Report.......................................................................................................... 70 Trend Definition Report ....................................................................................................... 70 Panel Trend Definition Report ............................................................................................. 70 Trend Data Detail Report..................................................................................................... 70 Totalization Log Report ....................................................................................................... 70

Scheduler ............................................................................................................................... 71

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System Profile ........................................................................................................................ 71 Command Priority Array Strings .......................................................................................... 71 BACnet Address Table ........................................................................................................ 71 BLN Definition...................................................................................................................... 71 FLN Devices ........................................................................................................................ 72 Device Re-Initialization ........................................................................................................ 73 Device Communication Control ........................................................................................... 73 Who-Is Diagnostic Tool ....................................................................................................... 74

Time-of-Day Scheduling......................................................................................................... 74 Trend Editor............................................................................................................................ 74

Trend Definitions.................................................................................................................. 74 User Accounts ..................................................................................................................... 74 Command Priority ................................................................................................................ 74 Insight Account Tab............................................................................................................. 76 BLN Account TAB................................................................................................................ 76 BACnet Export ..................................................................................................................... 77

Chapter 7–BACnet Scheduling................................................................................................... 79

BACnet Scheduling Theory ...................................................................................................... 79

Schedule Object ..................................................................................................................... 80 BACnet Schedule Object Operation.................................................................................... 80

Command Object ................................................................................................................... 82 Calendar Object................................................................................................................... 85

BACnet and Insight Scheduling ................................................................................................ 86

Event Scheduling ................................................................................................................... 87 Start Stop Time Optimization (SSTO) .................................................................................... 87 BACnet Device Database Storage......................................................................................... 87 Schedule Object Properties that Can be Commanded.......................................................... 87

BACnet Scheduling Examples.................................................................................................. 88

BACnet Scheduling Example 1 .............................................................................................. 88 BACnet Scheduling Example 2 .............................................................................................. 90 BACnet Scheduling Example 3 .............................................................................................. 91 BACnet Scheduling Example 4 .............................................................................................. 91 BACnet Scheduling Example 5 .............................................................................................. 92

Chapter 8–BACnet Alarming....................................................................................................... 95

BACnet Alarming Theory .......................................................................................................... 95

Change Of Value (COV) Reporting........................................................................................ 95 Algorithmic Change Reporting ............................................................................................... 96 Intrinsic Reporting .................................................................................................................. 96

Notification Class ................................................................................................................. 97 Recipient List (Destinations)................................................................................................ 98

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Transitions and Event States............................................................................................... 99 Alarm Acknowledgement................................................................................................... 101 Alarm and Event Priority.................................................................................................... 101

BACnet and APOGEE ............................................................................................................ 102

Alarm Enable/Disable ........................................................................................................ 102 Floating Alarm Limits ......................................................................................................... 103 System Messages ............................................................................................................. 103 Initials................................................................................................................................. 103 Alarm Acknowledgements ................................................................................................. 103 Get Event Information vs. Alarm Summary ....................................................................... 103 Unknown BACnet Alarms .................................................................................................. 104 Life Safety Alarms.............................................................................................................. 104 BACnet Text Messages..................................................................................................... 104 Alarm Priority ..................................................................................................................... 104 Alarm Messages ................................................................................................................ 105

BACnet Browser................................................................................................................... 105 Point Objects ..................................................................................................................... 105

RENO Notification ................................................................................................................ 106 APOGEE GO........................................................................................................................ 106

BACnet Alarming Example ..................................................................................................... 106

L2SL Point............................................................................................................................ 107 LTD Point ............................................................................................................................. 108 SAT Point ............................................................................................................................. 109 SSP Point ............................................................................................................................. 112 Notification Class.................................................................................................................. 113

Alarm Message Definition.................................................................................................. 114

Chapter 9–BACnet Trending..................................................................................................... 117

BACnet Trending Theory ........................................................................................................ 117

BACnet Trending in APOGEE ................................................................................................ 120

APOGEE Trending: Non-BACnet vs. BACnet ..................................................................... 120 Scheduling Trends ............................................................................................................... 120 Scheduling Trend Collections .............................................................................................. 120

Notification Class ............................................................................................................... 121

Chapter 10–BACnet Tools......................................................................................................... 127

BAS-o-matic Protocol Analyzer .............................................................................................. 127

Obtaining BAS-o-matic......................................................................................................... 127 Connecting to a Network...................................................................................................... 128

Connecting a Separate BAS-o-matic Computer................................................................ 128 Using the Insight Workstation for BAS-o-matic ................................................................. 129

Commissioning Tool Support for APOGEE BACnet Field Panels.......................................... 129

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Firmware Loading Tool ........................................................................................................ 129 MMI Database Transfer........................................................................................................ 129

Build System Profile........................................................................................................... 129 Backup/Restore ................................................................................................................. 129 Terminal Emulation............................................................................................................ 130

Copy Field Panel .................................................................................................................. 130 Point Transfer....................................................................................................................... 130 Non-Field Panel Data Transfer ............................................................................................ 131 Point Summary Report ......................................................................................................... 131 Point Checkout Data ............................................................................................................ 131 Commissioning Report Generator........................................................................................ 131

Insight BACnet Communications Tools .................................................................................. 132

Multiple Device Configuration .............................................................................................. 132 Global Broadcast Who-Is ..................................................................................................... 133 Custom Send Who-Is Diagnostic Tool ................................................................................. 133 Enable Device Discovery ..................................................................................................... 134 BACnet Device Communication Control .............................................................................. 134 BACnet Communication Diagnostic ..................................................................................... 135

Glossary...................................................................................................................................... 139

Index............................................................................................................................................ 149

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About this Application Guide

This section discusses the following topics:

Purpose of this guide.

How this guide is organized.

Suggested reference materials and Web sites.

It also provides information on symbols used, how to access help, and where to direct comments about this guide.

Purpose of this Guide

This application guide discusses the Building Automation and Control networks (BACnet®) standard data communication protocol and gives details about the implementation of the Insight BACnet Option and the APOGEE BACnet Field Panels. This guide is intended to supplement all of the other APOGEE BACnet system documentation (online help, Getting Started, User Guides, etc.) by providing information not contained in those documents.

It is assumed that the reader is technically capable of understanding the concepts of building automation and database management. It also assumes that they are familiar with APOGEE concepts and understand its operations.

This application guide should help Branch and customer personnel understand how BACnet has been implemented in the APOGEE Building Automation System.

How this Guide is Organized

This application guide contains the following chapters:

Chapter 1, Introduction to BACnet, describes BACnet in general terms and how it relates to the APOGEE Building Automation System.

Chapter 2, BACnet Objects and Services, describes BACnet Objects and Services theory, and how the Insight application and the BACnet Browser are used to access objects and their properties.

Chapter 3, BACnet Interoperability, describes the ability of APOGEE BACnet devices to integrate with BACnet products made by different manufacturers into a single system.

Chapter 4, BACnet Communications, describes BACnet communication theory in relation to the Insight application.

Chapter 5, BACnet Field Panel, describes the features and functions of the APOGEE BACnet field panel as well as the firmware used to operate it.

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Chapter 6, Insight BACnet Option, describes the Insight BACnet Option and the changes to the Insight application since Revision 3.2

Chapter 7, BACnet Scheduling, describes BACnet scheduling theory as it relates to scheduling in the APOGEE Building Automation System.

Chapter 8, BACnet Alarming, describes BACnet alarming theory, how it relates to the APOGEE Building Automation System, and how to set up alarming in an APOGEE Building Automation System.

Chapter 9, BACnet Trending, describes BACnet trending theory and trending in an APOGEE Building Automation System.

Chapter 10, BACnet Tools, describes tools for analyzing BACnet communications in an APOGEE Building Automation System.

The Glossary describes various terms and acronyms used in this application guide.

The Index helps you locate information presented in this guide.

Suggested Reference Materials

In addition to this application guide, you may also want to become familiar with the following reference materials:

ANSI/ASHRAE Standard 135-2004 available at: www.ashrae.org.

BACnet Web site: www.BACnet.org

BACnet International (BI) Web site: www.bacnetinternational.org

See the Glossary for other references.

Symbols

The following table lists the symbols used in this guide to draw your attention to important information.

Notation Symbol Meaning

CAUTION:

Indicates that equipment damage, or loss of data may occur if the user does not follow a procedure as specified.

Note

Provides additional information or helpful hints that need to be brought to the reader's attention.

Tip

Suggests alternative methods or shortcuts that may not be obvious, but can help the user better understand the capabilities of the product.

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Getting Help

For more information about regulated facilities, contact your local Siemens representative.

Where to Send Comments

Your feedback is important to us. If you have comments about this guide, please submit them to: [email protected]

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Chapter 1–Introduction to BACnet

Chapter 1 describes BACnet in general terms and how it relates to the APOGEE Building Automation System. It includes the following topics:

What is BACnet?

Why BACnet was Developed

How BACnet was Developed

Certification

BACnet Implementation within the APOGEE Automation System

What is BACnet?

BACnet is an acronym for Building Automation and Control networks. It is the name for an ASHRAE and ANSI standard data communication protocol, which is a set of rules governing the exchange of data over a computer network. The rules govern hardware (for example, cable types, system topology) and software (for example, formation of request or command messages). The rules are in a published specification (ANSI/ASHRAE Standard 135-2004) that defines what is required to conform to the protocol.

Figure 1. The BACnet Logo.

The BACnet specification also defines the BACnet components: the object and services model, the network layer protocol, and a selection of various network transport technologies. (See Table 1.) As a result, the BACnet specification can govern the design of workstations, controllers, gateways, routers, and diagnostic tools.

Table 1. Components of BACnet.

BACnet Components Description

Objects Methods of Representing Information

Services Methods of Making Requests and Interoperating

LANs and Internetworking Transport Systems

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BACnet was designed specifically for all building automation applications:

HVAC control

Fire detection and alarm

Lighting control

Security

Elevator interface

Utility company interface

To achieve these capabilities, BACnet specifies nearly all of the common building control and monitoring functions, for example: analog and binary inputs, outputs, and values; control loops; schedules, etc.

One of the strengths of BACnet is in accommodating future building automation applications. A vendor can easily add to the existing objects and services. This is not only expected, it is encouraged. Of course, for proprietary features to interoperate, vendor cooperation is required.

Thousands BACnet sites are already operating both in the USA and in various countries around the world.

Why BACnet was Developed

The idea for BACnet was fostered by building automation system (BAS) users within ASHRAE. They believed that BAS technology had progressed sufficiently that standards could be established such that products from different manufacturers could all work together. In other words, BACnet could enable control product interoperability.

The benefits of interoperability to BAS users are:

One workstation can work with remote panels and controls from different manufacturers

More competitive bidding on expansions and additions

Freedom to select the manufacturer(s) that best meet the requirements of the project at the best price

Allows the addition of technologies and services as they become available, regardless of manufacturer

A higher likelihood that a current system can be expanded without having to replace it entirely–thus protecting the control system investment

The benefits of BACnet to controls system manufacturers and suppliers are:

There is no charge (license fee) for its use–anyone is permitted to develop and use implementations without cost.

It is maintained by an ASHRAE committee representing all sectors of the industry.

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It is designed specifically for building control.

It is designed to be implemented in devices of all sizes.

It is designed to be readily enhanced and improved.

Its design is not tied to present technologies.


To develop BACnet, ASHRAE established a Standard Project Committee (SPC-135). The original BACnet standard was published in 1995. To help ensure acceptance, the standard had been thoroughly reviewed, studied and analyzed by the industry. The participants in the original testing became the National Institute of Standards and Technology (NIST) BACnet Interoperability Testing Consortium.

BACnet was introduced at the ASHRAE Winter Meeting in January, 1996. In the BACnet booth at the show, equipment from ten different vendors running various types of computers, operating systems, and LAN types were successfully interconnected.

In 2001, the BACnet standard was updated with five addenda. In January 2003, the BACnet standard was approved as ISO Standard 16484-5 and as a European standard within the Committee for European Standardization (CEN).

The BACnet specification is maintained by ASHRAE Standing Standard Project Committee (SSPC) 135. This committee works on refining and expanding the standard.

Certification

Conformance of a product to the BACnet standard is the responsibility of an independent organization called the BACnet Testing Labs (BTL). The BTL develops testing tools and scripts to certify and list devices that conform to device profiles. The BTL consists of a core group sponsored by the BACnet International (BI) and individual manufacturer participation.

BACnet Implementation within APOGEE

The goals of Siemens Building Technologies’ implementation of BACnet are:

Support ANSI/ASHRAE standard BACnet IP throughout field panel and workstation architecture.

Meet BTL requirements for the field panel and the workstation.

Meet the global strategic BACnet requirements of Siemens Building Technologies, Inc.

Maintain/Enhance APOGEE Automation System features, functionality, performance, look and feel.

Maintain APOGEE Automation System backward compatibility.




Maintain support for LonWorks Floor Level Network (FLN), P1 FLN, OP Drivers, Insight options, and InfoCenter.

This is accomplished by the introduction of a BACnet MEC and MBC, and an enhanced Insight BACnet Client and Server Option along with Navigator Support (Commissioning Tool/Design Tool) and appropriate training, documentation, and rollout.

Chapter 2–BACnet Objects and Services

Chapter 2 describes BACnet Objects and Services, and how the Insight application and the BACnet Browser are used to access objects and their properties. It includes the following topics:

Objects Theory

Services Theory

Proprietary building automation systems from different manufacturers almost always have different functionality and different communication schemes. BACnet devices, however, all share a common communication standard regardless of manufacturer and the functionality within the device. This is accomplished through the use of objects to represent data and control, and services to convey requests, data, and information. The result is that each device looks the same on the communication medium.

Objects Theory

To standardize different systems from multiple of manufacturers, BACnet uses objects. An object is a collection of information about a particular function that is uniquely identified and is accessed over the communication medium in a standardized way.

All information in a BACnet system is represented using objects. Standardized objects make all of the devices within a BACnet system look alike. Examples of objects are analog and binary inputs and outputs, schedules, control loops, alarms, logical groupings of points that perform a specific function, software calculations, and software processes.

Of course, a specific object can only exist for a manufacturers’ product if the product has that function that the object represents. For example, you cannot write to the schedule object of a BACnet device if the device has no schedule function.

Figure 2. Examples of BACnet Objects.



Properties of Objects

All BACnet objects have a set of properties that are used to either get information from the object, or give information and commands to the object. An object’s properties are often represented as a table with two columns. On the left is the name or identifier for the property, and on the right is the property’s value.

Some properties are read only meaning that you can look at the property value, but cannot change it. Some properties can be changed (written).

Standard objects can have both required properties and optional properties. Vendors can also create non-standard objects and/or properties.

In the APOGEE Automation System, if a property exists in a BACnet field panel, then the property may be accessed in one of three ways:

Through the field panel MMI.

Through the BACnet Object Browser–an Insight application feature in which the properties are listed in tabular form where they can be read or written (if applicable).

Through the Insight application’s windows and dialog boxes–if the property needs to be read, written, or commanded for the application being used. Some properties may be renamed. For example, the Object_Identifier property is called the Instance Number in the Insight application.

A property of every BACnet object that is responsible for identifying the object is called the Object_Identifier. It is a numerical value that must be unique within the BACnet device in which it resides. (Property names appear with underbars in the BACnet specification.)

Each BACnet object also has an Object_Name property. This is a string of printable characters that also must be unique within the BACnet device in which it resides.

To further assist a user in identifying and managing objects within a BACnet device, each BACnet object has a Description property. It is a string of printable characters, but does not have to be unique in the BACnet device.

Figure 3. BACnet Analog Input Representation of a Temperature Sensor.

Figure 3 is an example of a temperature sensor that might be represented as a BACnet Analog Input object. The example shows a few of the properties that might be available with this object. In practice there would be many more properties than those shown.


Objects Theory

The Object_Name property has the value of SPACE TEMP and Object_Type property has the value of ANALOG INPUT. The Present_Value property is the temperature that the sensor is currently reading (72.3). The remaining properties represent other information about the sensor object, such as whether it is functioning normally, and the values of the High and Low Limits for alarming purposes.

The OBJECT_TYPE Property

Another property of all BACnet objects is called the Object_Type. In BACnet, 23 standard object types have been established to contain much of the information that can be associated with a building automation system. Table 2 lists these object types in seven categories.

Table 2. BACnet Standard Object Types.

Object Type

Point-like

Binary Input Binary Output Binary Value

Analog Input Analog Output Analog Value

Multi-state Input Multi-state Output Multi-state Value

Event Reporting

Event Enrollment Notification Class

Scheduling/Logging

Schedule Calendar Trend Log

Control

Program Loop Averaging

Life Safety

Life Safety Point Life Safety Zone

Grouping

Group Command

Device Level

Device File

Each occurrence of an object within a device is marked by the Instance Number. For example, if there are three Notification Class objects in a device, they will carry Instance Numbers 1, 2 and 3, respectively. Some objects have the Instance Number as a property. For example, in the Notification Class object, the value of its Notification_Class property is its Instance Number. The Instance Number is part of what makes up an object’s Object_Identifier property. The relationship is:

Object_Identifier = Object_Type + Instance Number



Command Priority Properties

BACnet has an application-controlled prioritization mechanism, the Command Priority Array, that determines which application is commanding an object property. The Command Priority Array is similar to the Point Command Priority in the APOGEE Automation System.

The BACnet properties that implement the command priority array are Priority_Array and Relinquish_Default. Every commandable object property supports a 16-slot Priority_Array plus a Relinquish_Default value that serves as a default if no applications are controlling the object value when all 16 slots are empty. Figure 4 shows the standard priorities within the 16 slots along with BACnet’s recommended applications for these priorities. The unused slots are available for other priorities.

Figure 4. BACnet Standard Priorities.

When multiple applications, each with a different priority, have active commands to the object, the object decides which to accept based on the relative priorities of the applications. As commands are set and released, the object will continuously re-evaluate which command to use. Each commanding application must stay in its own priority slot and not interfere with commands from other applications. If all commands are released, the object will default to the value held in the mandatory Relinquish_Default object property. Figure 5 shows an example of how the Command Priority Array operates.


Objects Theory

Figure 5. Example of the BACnet Command Priority Array Operation.

Command Priority Array vs. APOGEE

The BACnet Command Priority Array, which is similar to APOGEE’s Point Command Priority, manages the Present_Value property. Each Insight application that commands points has a configurable default priority that is used for point commands and releases.

Table 3 shows the Command Priority Array, along with the default mapping to APOGEE priorities. If desired, any of the six defaults can be changed by the user. For OPERATOR, the value in the table is used as the highest priority slot available for commanding. For example, the user can command at this priority and lower.

Table 3. BACnet Command Priority Array Mapped to APOGEE Priorities.

Slot BACnet Names APOGEE Priority

1 Manual Life Safety

2 Automatic Life Safety

3 Available

4 Available

5 Critical Equipment Control

6 Minimum On/Off

7 Available

8 Manual Operator OPERATOR

9 Available

10 Available SMOKE

11 Available

12 Available EMERGENCY

13 Available



Slot BACnet Names APOGEE Priority

14 Available PDL

15 Available

16 Available SCHEDULING, PPCL, NONE, TEC TOOL

Relinquish Default TEC APPLICATION

BACnet commands do not provide enough information for CFR-11 logging. As a result, the CFR-11 feature is not available in the BACnet field panel.

Modifying the Priority Array

The BACnet Priority Array can be modified from the System menu in the Insight System Profile application (Figure 6).

Figure 6. Accessing Priority Array from System Profile.

The BACnet Command Priority Array dialog box (Figure 7) displays the current Text and Abbreviated Text for each priority level.


Objects Theory

Figure 7. Command Priority Array Dialog Box.

The Edit button allows modification of the Priority Text and Abbreviated Text via the Modify Priority Text dialog box (Figure 8).

Figure 8. Modify Priority Text Dialog Box.

After clicking OK in both dialog boxes, the BACnet Command Priority Array dialog displays the updated priority text (Figure 9).



Figure 9. BACnet Command Priority Array after Modification.

Operation

The BACnet priority array operation can cause different operation at times when compared to the current APOGEE Automation System. The following scenario illustrates the change:

APOGEE Automation System:

1) The Scheduler application turns the lights off at the end of the workday. 2) A maintenance technician uses the Insight workstation to command the lights ON. 3) After performing service, the maintenance technician releases the command. 4) The end result is that the lights remain ON all night.

BACnet:

1) The equipment scheduler turns the lights off at the end of the workday. 2) A maintenance technician uses the Insight workstation to command the lights ON. 3) After performing service, the maintenance technician releases the command, returning control of the lights to the scheduler application, which turns the light OFF. 4) The lights remain OFF until commanded ON by the scheduler the next morning.

Another difference is that with BACnet, unlike the current APOGEE Automation System, commands cannot be dropped if the priority of the command is lower than the existing priority. The lower priority command must be properly entered into the command priority table for implementation whenever the higher priority command is released.

Another difference is that input points can be commanded when the object is out of service. The APOGEE Automation System selectively restricts input commanding for local points, but allows it for TEC subpoints. In BACnet, any point that is out of service can be commanded. Conversely, a physical point must be out of service to be commanded.


Objects Theory

Impact to MMI

The MMI must show which priority array entry is currently controlling the object. The MMI must also allow configuration of the highest priority allowed, such that priority levels used for life safety may be intentionally prohibited or allowed. See Point Objects for exact details.

Impact to PPCL

PPCL, like all of the other BACnet APOGEE applications that commands points, has a configurable default priority that is used for point commands and releases. Upon saving a new PPCL program in the Program Editor application, the Save As dialog box prompts the user to choose a priority level (Figure 10). The choices are established in the user’s account. PPCL programs will use the PPCL default priority level for point commands and releases if a priority is not specified in the statement. If a PPCL Command Priority (default priority) is not selected when a new program is saved, the PPCL value in the table (for example, BACnet priority level 16 if Table 3 were to apply) is used as the default priority level for the whole program.

Figure 10. PPCL Command Priority Setting.

A BACnet field panel positively acknowledges a command without changing the value if the value is under the control of higher priority. This is a change in operation from non-BACnet field panels, in which the PPCL interpreter would continuously re-command the point if the value didn’t change. Additionally, in a BACnet field panel, the RELEASE statement releases only the one priority level that is designated after the @ symbol. If no @ priority is defined, RELEASE will default to releasing level 16. Therefore, when using existing PPCL programs that use @Priority and Release, check if they have to be re-written to operate correctly.

When using the @<Priority> statements in BACnet field panels, only the top four APOGEE priorities (with their BACnet priority equivalents) can be used. For example. if Table 3 were the BACnet to APOGEE priority mapping for a field panel, then only OPERATOR, SMOKE, EMER and PDL can be used in the @<Priority> statements.



Impact to TEC Subpoints

In a BACnet field panel, commanding a TEC point will cause it to unbundle and use additional field panel memory. Like with any other point, the Present_Value will be set to the highest priority level.

When a TEC point is browsed, the Relinquish_Default property will contain the current Present_Value of the point, and the Priority_Array property will initially display as empty.

EEPROM points can only be written by commands with a priority higher (smaller priority number) than OPERATOR. Therefore, EEPROM points cannot be commanded by PPCL. If a remote third-party device commands an EEPROM point and the command has a priority higher than OPERATOR, the command will be blocked. The point’s Reliability property will display Unreliable because the Present Value and the Relinquish_Default disagree.

BACnet Device

A BACnet Device is a collection of objects that represent the functions actually present in a given real device. Figure 11 shows one example of how a group of objects make up a field panel type of BACnet device. Although only one instance of each kind of object is shown, a more typical field panel type of BACnet device might have 16 DI and DO objects, two or three Schedule objects, etc.

Figure 11. Example BACnet Device.

Note that a BACnet Device contains something called a Device object. The properties of this object are where information about the BACnet device resides. The properties include the device’s manufacturer and model number.

There is only one Device object in a BACnet Device. The Device object’s Object_Identifier property uniquely identifies the BACnet device on the communications network. Therefore, the Object_Identifier number must be unique on the network. The Device object also has an Object_Name property, which also must be unique on the network. Table 4 shows the properties of the Device object along with information about how they interface to the APOGEE Automation System.


Objects Theory

Table 4. Device Object Properties.

Property_Identifier Support Access Notes

Object_Identifier Yes Range is 0 to 4 MB. Configured in IP Settings.

Object_Name Yes Field Panel Name, limited to 30 characters, Configured in IP Settings.

Object_Type Yes Encoded name component “BACDev”

System_Status Yes OPERATIONAL status used to set Ready status

Vendor_Name Yes "Siemens BAU"

Vendor_Identifier Yes All Siemens ISA devices = 7

Model_Name Yes "Siemens BACnet EMEC"

Firmware_Revision Yes Firmware Rev String that is, "BCE V3.0 APOGEE”

Application_Software_Version Yes Firmware Rev String that is, "BCE3001”

Location Yes Limited to 40 characters, Configured in IP Settings.

Description Yes Limited to 40 characters, Configured in IP Settings.

Protocol_Version Yes 1

Protocol_Revision Yes 4

Protocol_Services_Supported Yes See Table 14 for a listing of supported services.

Protocol_Object_Types _Supported

Yes See the Object Summary table in Chapter 5–BACnet Field Panels.

Object_List Yes List of object Ids for all points in this field panel.

Max_APDU_Length_Accepted Yes 1497

Segmentation_Supported Yes BACNET_SEGMENTATION_TYPE_BOTH

Max_Segments_Supported Yes 32

VT_Classes_Supported No

Active_VT_Sessions No

Local_Time Yes Field Panel Time

Local_Date Yes Field Panel Date

UTC_Offset No The number of minutes between the local time and UTC time.

Daylight_Savings_Status Yes

APDU_Segment_Timeout Yes 3000

APDU_Timeout Yes 3000

Number_Of_APDU_Retries Yes 3

List_Of_Session_Keys No

Time_Sync_Recipients No

Max_Master No

Max_Info_Frames No




Device_Address_Binding Yes

Database_Revision Yes Logical revision number for the database, incremented when objects are created and/or deleted, an object's name is changed, or a database restore is performed.

Configuration_Files Yes List of files to be backed up. Valid only during the backup procedure.

Last_Restore_Time Yes Time of last file download. Applies only to BACnet file transfer services.

Backup_Failure_Timeout Yes Writable How long to wait before aborting a backup or restore operation.

Active_COV_Subscriptions Yes A list of active subscriptions. Applies to the server side.

Slave_Proxy_Table No

Manual_Slave_Address_Binding No

Auto_Slave_Discovery No

Slave_Address_Binding No

Profile_Name No

Point-Like Objects

Table 2 lists the BACnet objects that resemble points in a building automation system. As with all BACnet objects, point-like objects are just representations of a BACnet device’s points to other BACnet devices on the network. The points’ structure inside of the manufacturer’s device may be entirely different–perhaps representing the manufacturer’s proprietary and/or legacy software architecture.

The following are some of the highlights of the point-like objects.

Analog Input Object

The Analog Input Object is a representation of a physical analog input point in the BACnet device. Table 5 shows the properties of the Analog Input object along with information about how they interface to the APOGEE Automation System.

Table 5. Analog Input Object Properties.


Object_Identifier Yes Range is 0 to 4 MB. Automatically assigned by default.

Object_Name Yes System Name, limited to 30 characters.

Object_Type Yes Encoded name component “AI”.

Present_Value Yes Writable REAL

Description Yes Writable Limited to 16 characters.


Objects Theory


Device_Type Yes Text corresponding to the APOGEE LAI sensor type is as follows: "current" "voltage" "pneumatic" "100k Thermistor" "1K Platinum RTD" "LType" "custom"

Status_Flags Yes IN_ALARM = true if point is in alarm, else false. FAULT = true if point is failed, else false. OVERRIDDEN = true if point is in hand mode, else false. OUT_OF_SERVICE = false.

Event_State Yes If point is in alarm, then Event_State = OFFNORMAL, else if point is failed, then Event_State = FAULT, else Event_State = NORMAL.

Reliability Yes If point is in trouble, then Reliability = OPEN_LOOP, else if point is failed, then Reliability = UNRELIABLE_OTHER, else Reliability = NO_FAULT_DETECTED.

Out_Of_Service Yes Writable Must be set to override Present_Value.

Update_Interval No

Units Yes Writable Uses BACnet enumeration corresponding to fixed engineering units strings.

Min_Pres_Value No

Max_Pres_Value No

Resolution Yes Slope

COV_Increment Yes Writable COV Limit

Time_Delay Alarm Always equals zero.

Notification Class Alarm Writable

High_Limit Alarm Writable High Limit

Low_Limit Alarm Writable Low Limit

Deadband Alarm Always equals zero.

Limit_Enable Alarm If alarming enabled, then low_limit and high_limit both enabled.

Event_Enable Alarm Writable If alarming enabled, then to-offnormal, to-fault, and to-normal all set to TRUE.

Acked_Transitions Alarm Indicates which of the transitions have been acknowledged, TO_OFFNORMAL, TO_FAULT, TO_NORMAL.

Notify_Type Alarm Always = “Alarm”

Event_Time_Stamps Alarm Timestamps of the following event transitions, TO_OFFNORMAL, TO_FAULT, TO_NORMAL.

Profile_Name No

The Present_Value property is the current value of the point. Note that the Out_Of_Service property must be TRUE, before you can write a value into the Present_Value property.



Analog Output Object

The Analog Output Object is a representation of a physical analog output point in the BACnet device. Table 6 shows the properties of the Analog Output object along with information about how they interface to the APOGEE Automation System.

Table 6. Analog Output Object Properties.




Object_Type Yes Encoded name component “AO”.



Device_Type Yes Associated APOGEE Point type.



Reliability Yes if point is in trouble, then Reliability = OPEN_LOOP, else if point is failed, then Reliability = UNRELIABLE_OTHER, else Reliability = NO_FAULT_DETECTED.

Out_Of_Service Yes Always FALSE

Units Yes Uses BACnet enumeration corresponding to fixed engineering units strings.

Min_Pres_Value No

Max_Pres_Value No

Resolution Yes Slope

Priority_Array Yes For commanding the present value.

Relinquish_default Yes For releasing the present value when the Priority Array is empty.






Deadband Alarm Always equals zero.




Objects Theory



Notify_Type Alarm Always equals Alarm.


Profile_Name No

The Present_Value property is the current value of the point. Since this is an output, its Present_Value property is always writeable.

Analog Value Object

The Analog Value Object is a representation of a virtual analog output point or a software parameter in the BACnet device. Table 7 shows the properties of the Analog Value object along with information about how they interface to the APOGEE Automation System.

Table 7. Analog Value Object Properties.




Object_Type Yes Encoded name component “AV”






Out_Of_Service Yes Always FALSE.

Units Yes Uses BACnet enumeration corresponding to fixed engineering units strings.











Deadband Alarm Always equal zero.






Profile_Name No

The Present_Value property is the current value of the point. Note that it should be writeable if it is commandable or if Out_Of_Service is TRUE.

Binary Input Object

The Binary Input Object is a representation of a physical binary or digital input point in the BACnet device. Table 8 shows the properties of the Binary Input object along with information about how they interface to the APOGEE Automation System.

Table 8. Binary Input Object Properties.




Object_Type Yes Encoded name component “BI”.

Present_Value Yes Writable Binary Value


Device_Type Yes Associated APOGEE Point type



Reliability Yes if point is in trouble, then Reliability = OPEN_LOOP, else if point is failed, then Reliability = UNRELIABLE_OTHER,else Reliability = NO_FAULT_DETECTED.

Out_Of_Service Yes Writable Must be set in order to override the Present_Value.


Objects Theory


Polarity Yes Normally Closed

Inactive_Text Yes Correspond with first entry in the points State Text Table.

Active_Text Yes Correspond with second entry in the points State Text Table.

Change_Of_State_Time No

Change_Of_State_Count No

Time_Of_ State_Count_Reset

No

Elapsed_Active_Time Yes Writable Totalization

Time_Of_ Active_Time_Reset

Yes Totalization_Reset_Time



Alarm_Value Alarm Specifies what the Present_Value is when the point is in Alarm.



Notify_Type Alarm Always equals Alarms


Profile_Name No

The Present_Value property is the current value of the point. Note that the Out_Of_Service property must be TRUE for the Present_Value to be writeable. The Polarity property indicates the relationship of the physical state of the input to the logical state represented by the Present_Value property.

Binary Output Object

The Binary Output Object is a representation of a physical Binary output point in the BACnet device. Table 9 shows the properties of the Binary Output object along with information about how they interface to the APOGEE Automation System.

Table 9. Binary Output Object Properties.




Object_Type Yes Encoded name component “BO”.











Polarity Yes Inverted






No




Minimum_Off_time No

Minimum_On_time No



Time_Delay Alarm Proof Delay


Feedback_Value Alarm Current value of the proof point for APOGEE proof points, set equal to the Present_Value for points without proofing.





Profile_Name No

The Present_Value property is the current value of the point. Since this is an output, its Present_Value property is always writeable.


Objects Theory

Binary Value Object

The Binary Value Object is a representation of a virtual Binary output point or a software parameter in the BACnet device. Table 10 shows the properties of the Binary Value object along with information about how they interface to the APOGEE Automation System.

Table 10. Binary Value Object Properties.




Object_Type Yes Encoded name component “BV”.












No




Minimum_Off_time No

Minimum_On_time No





Alarm_Value Alarm Specifies what the Present_Value is when the point is in Alarm.








Profile_Name No


Multi-State Input Object

The Multi-state Input Object has not analogy in the APOGEE BACnet field panel and is not supported

Multi-State Output Object

The Multi-state Output Object is a representation of a physical Multi-state output point in the BACnet device. This point supports L2SL, L2SP, LOOAL, LOOAP, LFSSL, and LFSSP points in APOGEE field panels. Table 11 shows the properties of the Multi-State Output object along with information about how they interface to the APOGEE Automation System.

Table 11. Multi-state Output Object Properties.




Object_Type Yes Encoded name component “MO”.

Present_Value Yes Writable Unsigned






Out_Of_Service Yes Writable


Objects Theory


Number_Of_States Yes Correspond to size of State Text Table.

State_Text Yes Corresponds with State Text Table.


Relinquish_default Yes For releasing the Present_Value when the Priority Array is empty.



Feedback_Value Alarm Current value of the proof point for APOGEE proof points, set equal to the Present_Value for points without proofing.





Profile_Name No

The Present_Value property is the current value of the point. Since this is an output, its Present_Value property has a Conformance Code of W meaning that it is always writeable.

Multi-State Value Object

The Multi-state Value Object is a representation of a virtual Multi-state output point or a software parameter in the BACnet device. This point is the equivalent of the LENUM point in the APOGEE field panel. Table 12 shows the properties of the Multi-state Value object along with information about how they interface to the APOGEE Automation System.

Table 12. Multi-state Value Object Properties.




Object_Type Yes Encoded name component “MV”.

Present_Value Yes Writable Unsigned








Out_Of_Service Yes Writable

Number_Of_States Yes Correspond to size of State Text Table.

State_Text Yes Corresponds with State Text Table.


Relinquish_default Yes For releasing the Present_Value when the Priority Array is empty.



Alarm_Values Alarm

Fault_Values Alarm

Event_Enable Alarm Writable




Profile_Name No


Other Objects Supported by APOGEE BACnet Field Panels

Other BACnet objects that are supported by APOGEE BACnet Field Panels are:

Calendar Object

Command Object

File Object

Notification Class Object

Schedule Object

Trend Log Object

Calendar Object

See Chapter 7-BACnet Scheduling for details.


Objects Theory

Command Object


File Object

This object is involved with the database uploads and downloads of an APOGEE field panel. Table 13 shows the properties of the File object along with information about how they interface to the APOGEE Automation System.

Table 13. File Object Properties.




Object_Type Yes Encoded name component “FI”.

Description Yes Limited to 16 characters.

File_Type Yes

File_Size Yes Writable

Modification_Date Yes

Archive Yes Writable

Read_only Yes

File_Access_Method Yes

Record_Count No

Profile_Name No

Notification Class Object

See Chapter 8-BACnet Alarming for details.

Schedule Object


Trend Log Object

See Chapter 9-BACnet Trending for details.

Viewing with the BACnet Browser

BACnet objects and their properties can be viewed using the BACnet Object Browser. The Object Browser is accessed from the Tools menu in System Profile. A Building Level Network (BLN) must first be chosen to un-gray the BACnet Object Browser.



Figure 12. Accessing the BACnet Object Browser.

Then the navigation pane in the browser can be used to choose the desired BACnet device (field panel). Choosing a BACnet device will cause its objects to display in the navigation panel and the properties of that device to display on the right side of the screen (assuming you select View Device Properties from the View selection). See Figure 13.


Services Theory

Figure 13. BACnet Object Browser Screen.

Services Theory

This section is included to provide a greater understanding of how BACnet operates. Most of the operation of BACnet services is behind the scenes and not visible to the user.

BACnet services are the messages that the BACnet devices send to each other. Services are the means by which one BACnet device acquires information from another device, commands another device to perform some actions, or announces to one or more devices that some event has taken place.

BACnet is based on a Client-Server communications model, and these messages are carried out by the server at the request of the client. Therefore, BACnet messages are service requests. A client computer sends a service request to a server computer that then performs the service and reports the result back to the client. Each service request issued and service acknowledgment (reply) returned becomes a message packet transferred over the network from the sending to the receiving device.

The BACnet message-passing and object access services are divided into five groups or classes of Application Services:

Object Access Services–Provide the means to read, modify and write properties, as well as add and delete objects.



Alarm and Event Services–Deal with changes in conditions seen by a BACnet device such as problems, error conditions, sensors reading out of normal range or alarms returning to normal operation. Also included are Changes-Of-Values or COVs.

File Access Services–Used to read and manipulate files in BACnet devices. In BACnet, files represent groups of data of arbitrary length and meaning; they do not necessarily relate to any kind of mass storage device. Every BACnet-accessible file has a File Object associated with it.

Remote Device Management Services–Provide a number of assorted functions, including operator control, specialized message transfer, addressing/auto-configuring functions, discovery of devices and objects, device control, time synchronization file access, reading, and writing.

Virtual Terminal Services–Used by an operator to establish a bi-directional text-based connection with an application program executing in a remote device. In effect, for the duration of a VT session established with the remote device, the operator's device looks like a terminal connected to the remote application program.

Service requests are issued or processed by application program software running on the BACnet device. In the case of an operator workstation, the software might maintain a display of several sensor inputs and would periodically issue service requests to the appropriate objects in the target devices to obtain the latest values of the inputs. In the monitored device, the service request would be processed in its application program and the reply containing the requested data returned (Figure 14).

Figure 14. Example Service Request and Reply.

Services are categorized as Confirmed in which a reply, typically with data, is expected, or Unconfirmed in which no reply is expected. BACnet devices are not required to implement every single Service. Just one Service, ReadProperty, is required to be processed by all BACnet devices. Depending upon the function and complexity of the device, additional Services may be initiated or executed.


Services Theory

Services Supported

The APOGEE BACnet solution only supports the services listed in Table 14.

Table 14. Services Supported.

Service Name

ACKNOWLEDGE_ALARM

ADD_LIST_ELEMENT

ATOMIC_READ_FILE

ATOMIC_WRITE_FILE

CONFIRMED_COV_NOTIFICATION

CONFIRMED_EVENT_NOTIFICATION

CONFIRMED_PRIVATE_TRANSFER

CONFIRMED_TEXT_MESSAGE

CREATE_OBJECT

DELETE_OBJECT

DEVICE_COMMUNICATION_CONTROL

GET_ALARM_SUMMARY

GET_ENROLLMENT_SUMMARY

GET_EVENT_INFORMATION

I_AM

I_HAVE

READ_PROPERTY

READ_PROPERTY_MULTIPLE

READ_RANGE

REINITIALIZE_DEVICE

REMOVE_LIST_ELEMENT

SUBSCRIBE_COV

TIME_SYNCHRONIZATION

UNCONFIRMED_COV_NOTIFICATION

UNCONFIRMED_EVENT_NOTIFICATION

UNCONFIRMED_TEXT_MESSAGE

WHO_HAS

WHO_IS

WRITE_PROPERTY

WRITE_PROPERTY_MULTIPLE




Services Not Supported

The APOGEE BACnet solution does not support the services listed in Table 15.

Table 15. Services Not Support.

Service Name

AUTHENTICATE

LIFE_SAFETY_OPERATION

READ_PROPERTY_CONDITIONAL

REQUEST_KEY

SUBSCRIBE_COV_PROPERTY

UNCONFIRMED_PRIVATE_TRANSFER

UTC_TIME_SYNCHRONIZATION

VT_CLOSE

VT_DATA

VT_OPEN

Chapter 3–BACnet Interoperability

Chapter 3 describes the ability of APOGEE BACnet devices to integrate with BACnet products made by different manufacturers into a single system. It includes the following topics:

Interoperability

Interoperability

Certification

BACnet Device Profiles

APOGEE BACnet Field Panel Interoperability

Insight Interoperability

Interoperability

BACnet Interoperability is the ability to integrate BACnet products made by different manufacturers into a single system. Interoperability does not mean that installations must have multiple vendors, just that the site can have multiple BACnet vendors if desired. Many automation system users prefer the benefits of dealing with a single vendor, and a system using the BACnet protocol in no way prevents this.

Note that Interoperability is not plug-and-play. You still have to make choices about what functionality is needed. Also, BACnet interoperability does not address:

Configuration

Programming (programming language)

User interface (look and feel)

Some obstacles to interoperability are:

Many properties are optional.

Manufacturers may interpret the specification differently and make different design assumptions.

Differing character sets are used around the world.



Certification

BACnet is a registered trademark of ASHRAE. ASHRAE does not endorse, approve, or test products for BACnet compliance. That is the responsibility of BACnet International (formerly the BACnet Manufacturers Association and the BACnet Interest Group - North America). To test manufacturers’ BACnet devices for interoperability and certify the results, BACnet International (BI) established the BACnet Testing Laboratories (BTL). The BTL logo is a trademark of BI. Products that have been successfully tested by the BTL are eligible to display the BTL logo as part of the listing process.

The main functions of the BTL are to:

Sponsor an annual BACnet Interoperability Workshop.

Develop testing procedures and rules to certify that BACnet devices conform to the BACnet standard so that the devices may carry the BTL certification mark (Figure 15).

Figure 15. BACnet Testing Laboratories Certification Mark.

The APOGEE BACnet Field Panels are BACnet Testing Laboratories (BTL) certified and listed BACnet Building Controllers (B-BC). They carry the BTL certification mark and can meet specifications calling for native BACnet field panels. They provide interoperability with third-party BACnet workstations.

The Insight Revision 3.7 workstation with the BACnet Option can be considered a native BACnet workstation. It has been developed to conform to the anticipated B-OWS test specification. The B-OWS test specification is not complete or approved, but the ANSI/ASHRAE Standard135-2004 includes a B-OWS profile that Siemens Building Technologies has followed.

Specifying BACnet

Specifying BACnet is challenging because the protocol purposely defines more functionality than any particular device will likely implement, and devices can vary greatly in their implementation of BACnet and BACnet functionality. A document called a Protocol Implementation and Conformance Statement (PICS) was devised to disclose BACnet information such that vendors, customers, and consulting engineers can understand the functionality implemented in a given device. From this information they can determine realistic expectations for interoperability between any given BACnet devices.


Interoperability

BACnet Interoperability Building Blocks (BIBBs) are defined in part of PICS. BIBBs are sets and groupings of functionality that can be easily mapped from device-to-device, to determine the functionality that is likely interoperable between devices.

Protocol Implementation and Conformance Statement

Protocol Implementation and Conformance Statement (PICS) is a BACnet specification sheet containing a list of a device's BACnet capabilities. Written in a standard format specified by ASHRAE, the PICS contains a general product description, a product's BACnet capabilities, available LAN options, and other items relating to character sets and special functionality.

Every BACnet device must have a PICS. Chapter 12–Appendix in BACnet Modular Equipment Controller (MEC) and Point Expansion Module (PXM) Start-up Procedures (145-025) contains the PICS for the APOGEE BACnet MEC.

Consulting engineers, vendors, and customers can use a PICS to determine what capabilities a BACnet device might have. The PICS may be used to determine what functionality devices are capable of supporting and what functionality is interoperable with other devices.

The PICS provides the following information about a BACnet device:

Product name, version, and description

Device profile (Annex L) to which the device conforms

B-OWS (BACnet Operator Workstation)

B-BC (BACnet Building Controller)

B-AAC (BACnet Advanced Application Controller)

B-ASC (BACnet Application Specific Controller)

B-SS (BACnet Smart Sensor)

B-SA (BACnet Smart Actuator)

BIBBs supported by the device

Data Sharing

Scheduling

Trending

Network Management

Alarm and Event

Device Management

Segmentation support and window size

Standard object types supported, plus an indication of objects that can be created and deleted by a third-party BACnet system/device

Analog Input, Output, Value

Averaging

Binary Input, Output, Value



Calendar

Command

Device

Event Enrollment

File

Group

Life Safety Point, Zone

Loop

Multi-State Input, Output, Value

Notification Class

Program

Schedule

Trend Log

Proprietary

Datalink and physical network layers support

BACnet/IP (Annex J)

BACnet Ethernet (10Base-2, 10Base-5, 10Base-T, Fiber)

BACnet ARCnet

BACnet MS/TP (EIA-485 Master-Slave/Token Passing)

BACnet Point-To-Point (EIA-232)

BACnet LonTalk

Device address binding support

Networking datalink options support

Router

BACnet Tunneling (Annex H)

BACnet/IP BBMD (BACnet Broadcast Management Device) (Annex J)

BACnet/IP Foreign Device

Character sets support

ANSI X3.4

ISO 10646 (ICS-4)

IBM/Microsoft DBCS

ISO 10646 (UCS2)

JIS C 6226

ISO 8859-1


Interoperability

BACnet Interoperable Building Blocks

BACnet Interoperable Building Blocks (BIBBs) are meaningful units of functionality of a BACnet device. The BIBBs of one BACnet device can be compared to the same BIBBs of another device to determine what functionality is likely to interoperate between the devices.



BIBBS descriptions are abbreviated as shown in the examples in Table 16.

Table 16. Data Sharing BIBBs Abbreviation Examples.

Description Client BIBBS (initiate) Server BIBBs (execute)

Data Sharing, Read Property DS-RP-A DS-RP-B

Data Sharing, Read Property, Multiple

DS-RPM-A DS-RPM-B

Data Sharing, Read Property, Conditional

DS-RPC-A DS-RPC-B

Data Sharing, Write Property DS-WP-A DS-WP-B

Data Sharing, Write Property, Multiple

DS-WPM-A DS-WPM-B

Each BIBB abbreviation ends with an A or B to denote its prescribed functional support. Definitions of A and B support are as follows:

A: User of data as a client–initiate function

B: Provider of data as a server–execute function

Achieving interoperability between two or more BACnet devices requires support in the device acting as the requester of data for the A type functionality, and support in the provider of the data for the B type of functionality. All devices expected to be interoperable must support the function required (BIBB) and the Initiate or Execute side of the functionality, depending on the role of the device (Figure 16).

Client

DS-RP-A

SA

G00

18R

1

DS-RP-B

DS

-WP

-B

Request Succeeded

DS

-WP

-A

Execute ControlRequest

Provide Information

Request InformationServer

Figure 16. BIBB Client and Server Interaction for Interoperability.


Interoperability

Figure 17 is an example Trending BIBB. Device B could be a BACnet field panel and device A could be workstation that archives the trended data.

Figure 17. Sample BIBB for Trending.

BIBBs interoperable functionality can be grouped into six categories or interoperability areas (IA):

Data Sharing

Scheduling

Trending

Network Management

Device Management

Alarm and Event Management

Data Sharing

The Data Sharing IA defines monitoring and commanding of property values, COV subscriptions, and object configuration. This functionality is similar to APOGEE logical point operations:

Read/write property

Read/write multiple properties

Read property conditional

COV (Change-of-Value)

Unsolicited COV

Scheduling

The Scheduling IA defines objects for calendars and scheduled commands for predefined lists of object properties:

Scheduling–internal

Scheduling–external



Trending

The Trending IA defines functionality for configuring trends and transferring trend data over the network:

Viewing and modifying trends–internal

Viewing and modifying trends–external

Automated trend retrieval

Network Management

Network management defines functionality for determining which devices are present on a given network:

Device connection establishment

Router configuration

Device Management

Device management defines functionality of some of the operational capabilities of a device, including:

Backup and restore device database

Device binding–discovery and connection

Device communication control

List manipulation

Object binding–discovery and connection

Object creation and deletion

Private transfer of message

Reinitialize device communications

Text message

Time synchronization

UTC time synchronization

Virtual terminal


Alarm and Event Management defines functionality including:

Annunciation and acknowledgment of alarms

Display of data indicating the basis for the alarm annunciation

Sharing of events for the purpose of logging or distributed control applications

Modification of alarm limits and routing


Interoperability

Production of summaries of the occurrence of such alarms and events.

BACnet supports two mechanisms for the generation of alarms and events:

Intrinsic Reporting–this relies on using properties that are part of, or "intrinsic" to, the object that is being monitored for alarms or events.

Algorithmic Change Reporting–this method is more general, but it also requires the overhead of an additional object called the Event Enrollment object. The intrinsic reporting method is preferred under circumstances where it meets the objectives of the intended application.

Alarm and event notification–internal

Alarm and event notification–external

Alarm acknowledgement

Alarm and event summary

Alarm enrollment summary

Alarm information

Life safety alarm

BACnet Device Profiles

BACnet Device Profiles indicate which BIBBs must be supported for each of a number of device types. Thus the profiles provide guidelines for interoperability. The device types include:

B-OWS (Operator Workstations), the target profile for APOGEE (the Insight workstation)

B-BC (Building Controllers), the target profile for the APOGEE BACnet field panels (MBC, MEC, PXC Compact)

B-AAC (Advanced Application Controllers)

B-ASC (Application Specific Controllers), the target profile for the BACnet TEC

Figure 18 shows the functional relationship and hierarchy of the device types in a building automation system. Included are the APOGEE Automation System devices.



Figure 18. Functional Relationship of BACnet Devices for Device Profiles.

Building Controller Profile (B-BC) and Operator Workstation Profile (B-OWS)

The B-BC and B-OWS profiles specify functionality in each of the interoperability areas that the BACnet committee deemed appropriate for field-panel class devices and workstations, respectively. However, the profiles are vague targets, specifying functionality at a high level and leaving many items optional or open to interpretation. The BACnet Test Labs (BTL), on the other hand, specifies a series of conformance tests and provides an automated testing framework that usually reduces ambiguity and improves chances for interoperability but also reduces a vendor’s opportunities for creativity.

Note that there is no standard BTL test for B-OWS compliance, but rather the tests are tailored to the functionality of the device at hand. For example, even though BTL will specify tests for all BIBBs listed in the following B-BC Profile section, devices that have no Multi-state Value objects will not be required to implement the Read Property service for Multi-state Value objects.

Each device sent to the BTL must be accompanied by an Electronic Protocol Implementation Conformance Statement (EPICS), which specifies the Objects and Services supported by the device. The BTL will use the EPICS to tailor the test suite to the specific implementation.

BACnet Building Controller (B-BC) Profile

A BACnet Building Controller (B-BC) is a general-purpose, field-programmable device capable of carrying out a variety of building automation and control tasks. Profiles are specified in terms of BIBBs, which are small pieces of functionality (Table 17).


Interoperability

Table 17. B-BC Profile.

B-BC Profile Description

Data Sharing Provides the values of any of its BACnet objects

Retrieves the values of BACnet objects from other devices

Allows modification of some or all of its BACnet objects by another device


Generates alarm/event notifications and the ability to direct them to recipients

Maintains a list of unacknowledged alarms/events

Notifies other recipients that the acknowledgment has been received

Adjusts alarm/event parameters

Scheduling Schedules output actions, both in the local device and in other devices, both binary and analog, based on date and time. There are no services specific to the Scheduling BIBBS. The Scheduling BIBBS specifies objects that must exist in devices.

Trending Collects and delivers (time, value) pairs

Device and Network Management

Responds to information about its status

Responds to requests for information about any of its objects

Responds to communication control messages

Synchronizes its internal clock upon request

Performs re-initialization upon request

Uploads its configuration and allow it to be subsequently restored

Commands half-routers to establish and terminate connections




BACnet Operator Workstation (B-OWS) Profile

The B-OWS is the operator's window into a BACnet system. While the B-OWS is primarily used for the operation of a system, it may be used for configuration activities that are beyond the scope of the BACnet standard. The B-OWS profile is specified in Table 18.

Table 18. B-OWS Profile.

B-OWS Profile Description

Data Sharing Archives data

Presentation of data (that is, reports and graphics)

Monitors the value of all BACnet object types, including all required and optional properties

Modifies setpoints and parameters


Operator notification and presentation of event information

Alarm acknowledgment by operators

Alarm summarization

Adjustment of alarm limits

Adjustment of alarm routing

Scheduling Modifies schedules

Displays start and stop times (schedule) of scheduled devices

Trending Modification of the parameters of a trend log

Displays and archives trend data

Device and Network Management

Displays information about the status of any device on the BACnet internetwork

Displays information about any object in the BACnet internetwork

Silences a device on the network that is transmitting erroneous data

Synchronizes the time in devices across the BACnet internetwork

Causes a remote device to reinitialize itself

Backups and restores the configuration of other devices

Commands half-routers to establish and terminate connections

Queries and changes the configuration of half-routers and routers

Chapter 4–BACnet Communications

Chapter 4 describes BACnet communication theory in relation to the Insight application. It includes the following topics:

BACnet Communication Theory

Insight Communication with the BACnet Option

BACnet Networking Technologies

A BACnet system requires an appropriate network technology to interconnect all of the devices. Although the BACnet specification defines a number of different network technology options, including ARCNET, MS/TP (RS-485), Point-to-point (RS-232) and LonTalk, the Insight BACnet Option supports direct connection only to the following:

BACnet/IP–Developed specifically for transporting BACnet messages between IP devices (over TCP/IP). It is the preferred networking technology for BACnet. BACnet/IP uses the IP address plus the UDP port address. BACnet/IP uses BACnet/IP Broadcast Management Devices (BBMDs) to get messages through IS/IT routers. For further details, see the BACnet/IP Broadcast Management Devices (BBMDs) section in this chapter.

Ethernet–Supports BACnet but with limitations, the biggest is that IS/IT routers typically block Ethernet broadcasts over the network. BACnet on Ethernet cannot get around these blocks. With BACnet on Ethernet, only devices on the same subnet are able to detect each other, unless the IS/IT department modifies their routers to allow Ethernet broadcast distributions. BACnet over Ethernet uses the Ethernet MAC addresses in each of the network devices.

Once the Insight workstation is connected to the network, it can successfully communicate with all other devices on the BACnet Internetwork, regardless of the networking technology used by the other devices.

Master-Slave/Token-Passing

Master-Slave/Token-Passing (MS/TP) uses a token to control access to a bus network. A master node can initiate the transmission of data when it holds the token. Slave nodes may transmit data in response to requests from master nodes. In MS/TP systems with multiple masters, the token determines which master can initiate transmissions.

APOGEE MS/TP slave nodes never hold the token. So, a means is provided to allow time for replies to be returned from slave devices. When a request that expects a reply is sent to a MS/TP slave node, the master waits for the reply to be returned before sending a request to another slave.



BACnet defines MS/TP for small networks with devices having lower speed requirements – 1 Mbps or less over twisted pair wiring. MS/TP over EIA-485 provides for small local networks that are up to 5,000 ft (1524 m) long using shielded twisted pair wiring.

BACnet MS/TP devices can be integrated into an APOGEE Automation System by using the BACnet MS/TP Driver. The driver software can be loaded into MBC Open Processor and MEC hardware. The driver communicates with Insight software, other APOGEE field panels, and the BACnet MS/TP devices. See the BACnet MS/TP Driver section in this chapter.

LonTalk Cautions

LonTalk is the Echelon Corporation’s LAN technology. The Insight BACnet Option cannot directly connect to a BACnet on a LonTalk network, but it can communicate with such networks via BACnet routers.

BACnet devices can utilize a LonTalk LAN to convey BACnet messages. This is identical to the way that BACnet messages are transported by Ethernet, ARCNET, and MS/TP. System designs, however, have steered away from BACnet messages on LonTalk. BACnet is optimized more for applications related to field panels and workstations. LonTalk, carrying proprietary LONMark messages, is the preferred method for unitary controller products, terminal unit controllers, and smart sensor/actuator applications.

CAUTION:

Although BACnet messages can be transported by LonTalk, this does not mean that native BACnet devices can automatically communicate with any other device on a LonTalk network. BACnet devices can only communicate with other BACnet devices. If a device on a LonTalk network uses Echelon’s proprietary technology, for example, it will not be able to understand BACnet messages, which are completely different.

As stated above, the Insight BACnet Option does not support direct connection to BACnet on a LonTalk network.

BACnet Protocol Model

The BACnet protocol is based on the seven-layer OSI model; however, BACnet is optimized by eliminating the transport, session and presentation layers (layers four, five and six) of the OSI model. Table 19 shows the BACnet layers and the equivalent OSI model layers.

For example, BACnet Master-Slave/Token-Passing (MS/TP) is a data link protocol. MS/TP provides services to the BACnet network layer similar to the way Ethernet’s (ISO 8802-2) Logical Link Control (part of the data link layer) does. MS/TP uses the services provided by the EIA-485 physical layer.

Some protocols, such as the Internet’s TCP/IP and BACnet’s BACnet/IP, are actually suites or stacks of protocols. They are layered sets of protocols which work together to provide a set of network functions. Each intermediate protocol layer uses the layer below it to provide a service to the layer above. The OSI model is an attempt to provide a standard framework within which to describe protocol stacks.



The Insight BACnet Option uses a BACnet protocol stack implementation called BACstac from a company named Cimetrics. BACstac is shipped with the Insight application, but is installed separately. BACstac’s version must be compatible with the version of the Insight application. For Insight Revision 3.7, use BACstac version 4.2-g. For Insight Revision 3.8 and 3.8.1, use BACstat version 4.3-e. See Insight® 3.8 Release Notes (125-3160-3P8) or later for compatibility information for other Insight revisions.

Table 19. BACnet Protocol Architecture.

BACnet Layers Equivalent OSI Layers

BACnet Application Layer

Application

N/A Presentation

N/A Session

N/A Transport

BACnet Network Layer

Network

ISO 8802-2 (IEEE 802.2)

Type 1 Ethernet

MS/TP

PTP

Data Link

ISO 8802-3 (IEEE 802.3)

Ethernet

ARCNET

EIA-485

EIA-232

Lon Talk Physical

For more information about the OSI model, see the Networking Essentials for APOGEE Application Guide (125-2011).

Basic BACnet Networking

This section describes how BACnet devices can be interfaced with other BACnet devices, non-native BACnet devices and BACnet devices on different networks. BACnet routers allow APOGEE BACnet/IP-based networks to interoperate with any other BACnet networks. The following examples can provide the basis for many combinations.

Native BACnet Devices On The Same LAN

Native BACnet means that the devices speak and understand BACnet. The devices may be interconnected using any of the approved BACnet LAN technologies. Most communication is direct, device-to-device (Figure 19).



BACnet Workstation

Sensors and Actuators

BACnetField Panels

BACnet LAN - Ethernet, ARCNET, MS/TP, LonTalk, or BACnet/IP

Vendors AVendors A

Vendors BVendors C

SA

G00

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Figure 19. Native BACnet Devices Communicating Directly.

Native BACnet Devices with Different LAN Technologies

To interconnect native BACnet devices on multiple LAN technologies, such as an Ethernet LAN to a MS/TP LAN, the network layer protocol is used. A BACnet router is the physical device that passes the messages on the network level. The BACnet standard contains the specifications for the BACnet router. See the BACnet Router vs. IP Router section in this chapter for more details.

Figure 20 shows an example of how two BACnet routers allow native BACnet devices on different networks to communicate. Messages between the ARCNET and MS/TP LANs pass through both routers via the BACnet Ethernet. If the BACnet workstation is running the Insight software, then the BACnet MS/TP devices and the BACnet ARCNET devices will appear in System Profile as ALN/BLN devices. Virtual points must be set up for an APOGEE BACnet field panel on Ethernet to communicate with a BACnet MS/TP or ARCNET devices to support alarms and trends.



BACnet Workstation



Ethernet toARCNET

BACnet Router

BACnetField Panel

Ethernet toMSTP

BACnet Router

BACnetField Panels

BACnetField Panels

BACnet LAN - Ethernet

Vendors AVendors A

Vendors C

SA

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Vendors AVendors A

BACnet LAN - ARCNET


Vendors AVendors A

BACnet LAN - MSTP

Figure 20. BACnet Devices on ARCNET and MS/TP LANs Communicating via BACnet Routers.

Native BACnet to Non-Native BACnet Devices

To interconnect native BACnet devices to non-Native BACnet devices, the Application Layer protocol is used. As Figure 21 shows, a gateway is the physical device used to pass the Application layer.

Because the messages of BACnet devices are different from the messages of non-BACnet devices, gateways translate these messages. A gateway also handles the Network, Data Link, and Physical layers by packaging the message for transport on the networks involved. Gateways are more complicated devices than routers.

A gateway is required to interface native BACnet devices to the non-BACnet devices of an existing, proprietary DDC system–such as an APOGEE Automation System. Gateways of this type usually must come from the maker of the proprietary system because detailed knowledge of the system’s proprietary protocol is required.

The Insight BACnet Option can act as a gateway to allow communication between BACnet devices and Insight workstations with APOGEE P2/Ethernet field panels.



BACnet Workstation


BACnetField Panels

BACnetto Vendor B

Gateway

Non-BACnetField Panels

BACnet LAN - Ethernet

Vendors A

Vendors B

SA

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Vendors A


Vendors BVendors B

Vendors BVendors B

Proprietary LAN

Figure 21. Native BACnet and Non-Native BACnet Devices Communicating through a Gateway.

BACnet Communications

BACnet/IP

BACnet messages can travel over networks that use the Internet Protocol (IP) by using BACnet/IP. With BACnet/IP, the BACnet device is an IP device (IP node), complete with its own IP address and IP protocol stack.

BACnet/IP devices communicate using BACnet messages wrapped in IP messages. BACnet/IP messages can be unicast (point-to-point)–from one device specifically to another device, or broadcast–from one device to many devices. Broadcast messages are also called multicast. Due to the limitation of sending broadcast (multicast) messages though IP routers, BBMDs (BACnet Broadcast Management Devices) are used to send broadcast messages around IP routers.

A BACnet broadcast message can be:

Local–on the same BACnet network as the source Remote–on another BACnet network (but not its own) Global–to all BACnet networks

Siemens Building Technologies, Inc. has standardized on BACnet/IP for APOGEE Automation Systems. Most competitors’ BACnet devices use BACnet/IP. If necessary, BACnet routers can be used o allow APOGEE’s BACnet/IP networks to interoperate with any other BACnet networks. The Insight BACnet Option and APOGEE BACnet 3.x field panels support using BBMDs, and each can provide the BBMD functionality.



BACnet Broadcast Management Device (BBMD)

Many IP routers prevent broadcast messages from being transmitted across a WAN. The BACnet protocol uses broadcast messages such as Who-Is, Who-Has, I-Am and I-Have to interrogate the network and determine what other BACnet devices exist. For these broadcast messages to be transmitted across IP routers that block such messages, one device on each subnet must be set up as a BACnet Broadcast Management Device (BBMD).

BBMDs are software applications that forward BACnet/IP broadcast messages across IP routers. A BBMD must appear on each side of an IP router. Communication between BBMDs is via unicast messages. There are two methods available to the BBMD to broadcast a message on a remote network–the one-hop and the two-hop. A BBMD can send broadcasts to another subnet or directly to another BBMD. Sending broadcasts to a subnet is called One-Hop Forwarding. Sending broadcasts to another BBMD is called Two-Hop Forwarding.

The BBMD does not need to be a physically distinct device. It is a software application that can be integrated into a device that performs other operations. For example, an Insight workstation with the BACnet Option can also function as a BBMD.

One-Hop

Figure 22 shows the one-hop or directed broadcast method. Device A on Network 1 initiates a broadcast message that is received by the other BACnet devices and the BBMD on Network 1. The BBMD sends the broadcast message to Network 2. The message has a destination address which causes the IP router for Network 2 to broadcast the message to all of the BACnet devices on that network.

SA

G00

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IP Router

IP Router

WAN

Network 1

Network 2

BBMD BACnetDevice

BACnetDevice

BACnetDevice

BBMD BACnetDevice

BACnetDevice

BACnetDevice

Sender

Figure 22. BBMD One-Hop (Directed Broadcast) Example.



Two-Hop

If the IP routers will not perform directed broadcasts, the two-hop or directed unicast method, shown in Figure 23 must be used. Device A on Network 1 initiates a broadcast message that is received by the other BACnet devices and the BBMD on Network 1. The BBMD on Network 1 sends a directed unicast message to the BBMD on Network 2. The Network 2 BBMD then broadcasts the message on its network.

SA

G00

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IP Router

IP Router

WAN

Network 1

Network 2

BBMD BACnetDevice

BACnetDevice

BACnetDevice

BBMD BACnetDevice

BACnetDevice

BACnetDevice

Sender

Figure 23. BBMD Two-Hop (Directed Unicast) Example.

The assumption with BACnet communications is that BACnet broadcast messages on any IP network (subnet) are used very infrequently, so their propagation should not cause any problems. So, care must be taken on all IP networks with BBMDs to prevent overwhelming the network with broadcast messages. Where broadcasts cannot be minimized, the use of another strategy, such as rearranging the subnets, should be examined.

Some other aspects of BBMD broadcasting are:

An Insight workstation that acts as a BBMD for a subnet must have a fixed IP address.

Every IP subnet with BACnet/IP devices must have a single BBMD so that broadcasts from the BACnet/IP devices on one subnet can reach the BACnet/IP devices on the other subnets.

Each BBMD has a Broadcast Distribution Table, which lists all the BBMDs, including itself, on the IP WAN. This table must be identical in all the BBMDs of a particular IP WAN. This table also tells which broadcast method, one-hop or two-hop, is to be used for each destination network.

The BBMD is not involved with non-broadcast communications (such as file transfers or reading and writing data values) between BACnet/IP devices. These communications are conducted directly.



There can be only one BBMD per IP subnet. Having more than one causes messages to be repeated in a loop.

BACnet Foreign Devices

BACnet foreign device registration allows access to a BACnet network’s broadcast messages from any BACnet device (workstation or field panel) having an IP connection but not having a BBMD or a multicast router on its subnet. Figure 24 shows an example of a BACnet foreign device workstation accessing a BACnet network’s broadcast messages. The BACnet foreign device workstation registers with the network’s BBMD and, thus, becomes a member of the BACnet/IP network. Then, for a specified time period (time to live time), the BACnet foreign device workstation will receive forwarded broadcast messages from the BBMD when they occur.

SA

G00

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IP Router

WAN

Network 1

Sender

BBMD BACnetDevice

BACnetDevice

BACnetDevice

BACnetForeign Device

Figure 24. BACnet Foreign Device receiving a Broadcast Message from a BACnet Network.

In addition, Figure 25 shows that the BACnet foreign device workstation can send messages to a BBMD with which it is registered, so they can be broadcasted.

SA

G00

12R

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IP Router

WAN

Network 1

Sender

BBMD BACnetDevice

BACnetDevice

BACnetDevice

BACnetForeign Device

Figure 25. BACnet Foreign Device Sending a Broadcast Message to a BACnet Network.




BACnet Router vs. IP Router

BACnet routers are devices that interconnect two or more BACnet networks to form a BACnet Internetwork. BACnet routers communicate via a single path–that is, all of the packets of a message take the same route to get to their destination. The BACnet networks that a BACnet router interconnects usually have different networking technologies. For example, a BACnet router may connect a BACnet Ethernet network to a BACnet/IP network. Table 20 lists some examples of BACnet routers.

Table 20. Examples of BACnet Routers.

Manufacturer Model Number

Description

Cimetrics BR2 BACnet/IP Router–connects BACnet to IT network; connects BACnet/IP to BACnet/Ethernet or BACnet MS/TP or BACnet/PTP or BACnet/ARCNET; can act as a BBMD; allows access to BACnet/IP network via modem.

Cimetrics B6000 BACnet/IP to MS/TP Router–connects BACnet/IP to MS/TP; DHCP; no mapping required.

PolarSoft® FreeRange™ Router

BACnet Router v1.12–routing between Ethernet 8802-3, BACnet/IP, PTP or MS/TP LANs; rugged enclosure; setup using built-in Web server.

IP Routers or IS Department Routers are devices that interconnect IP subnetworks into a single WAN. An IP Router determines the best path for a packet through the network when there are multiple paths. The IP Router is usually set up by the IS department to block IP broadcast messages, which in effect, blocks BACnet Broadcast messages. BBMDs are then used to propagate BACnet broadcasts to all IP subnets.

Chapter 5–BACnet Field Panel

Chapter 5 describes the features and functions of the APOGEE BACnet field panel as well as the firmware used to operate it. It includes the following topics:

APOGEE BACnet Field Panel

Firmware

MMI

APOGEE BACnet Field Panel

The APOGEE BACnet field panel is based on the APOGEE Ethernet field panel platform. The APOGEE BACnet field panel uses a combination of standard BACnet objects and services and proprietary functions to implement functions not covered by the BACnet standard.

Field Panel Hardware

All APOGEE field panels that have the Ethernet hardware can be upgraded to BACnet firmware. There are no new IO modules or FLN devices for BACnet. The BACnet firmware supports the same physical point IO and FLN devices as the non-BACnet Ethernet field panel.

Field Panel Features

APOGEE BACnet field panels retain much of the functionality of APOGEE non-BACnet field panels. Some of these functions include:

User Accounts and Access Control

Global Data Replication

Point Teams

PPCL Programming Language

Database upload and download

Support of P1 FLN devices

MMI menus and prompts

Where APOGEE and BACnet are incompatible, such as in network management and scheduling, new generic BACnet applications replace their non-BACnet counterparts.


Chapter 5–BACnet Field Panel


BTL Certification

The APOGEE BACnet field panels are BACnet Testing Laboratories (BTL) certified and listed BACnet Building Controllers. They carry the BTL certification mark and can meet specifications calling for native BACnet field panels. They provide interoperability with third-party BACnet workstations.

Chapter 6–Insight BACnet Option

Chapter 6 describes the Insight BACnet Option and the changes to the Insight software since Revision 3.2. It discusses the following topics:

Insight BACnet Option

Insight Changes for BACnet

Insight BACnet Option

The BACnet Option in Insight Revision 3.7 extends the capabilities of the BACnet Client & Server Option first introduced with Insight Revision 3.2.

The BACnet Client Option provides communication with both the APOGEE Automation System and third-party BACnet devices and systems, enabling functionality such as:

monitor and command BACnet objects

establish BACnet schedules and calendars

back up databases in BACnet devices

receive and acknowledge BACnet alarms, and

establish and read BACnet trend logs.

The BACnet Server Option can export proprietary protocol APOGEE point information as BACnet objects, so that a third-party BACnet client system may monitor and command APOGEE points, and monitor and acknowledge alarms within APOGEE proprietary networks and field panels.

Insight Revision 3.7 application runs on Microsoft® Windows® 2000, Windows XP, Windows Server 2003.

For more details on how each of these options interface with a BACnet network, see Insight Communication with the BACnet Option in Chapter 4–BACnet Communications.

Native BACnet and B-OWS

Insight Revision 3.7 software with the BACnet Option can be considered a native BACnet workstation because it conforms to the anticipated BACnet Operator Workstation (B-OWS) specification. The B-OWS specification is not complete or approved, but the ANSI/ASHRAE Standard 135-2004 includes a B-OWS profile that Siemens Building Technologies has followed.



Backward Compatibility

The addition of the BACnet option does not compromise APOGEE Automation System functionality or backward compatibility. All applications relating to APOGEE P2 BLN field panels, such as enhanced alarming, trending, point teams, scheduling, SSTO, PPCL, backup/restore, etc. are supported. Other Insight options such as OPC support, InfoCenter, specials, Fire/Security Workstation, RENO, and APOGEE GO are supported.


This section lists the changes made to Insight for BACnet. The emphasis is on the user interface changes (look and feel) since the details for using the dialog boxes are in the online Help and other chapters of this application guide.

BACnet Alarms

This section covers how the Insight software supports BACnet from a user's standpoint. For more detail about the operation of BACnet alarming, see Chapter 8–BACnet Alarming.

Point Priority

The Point Priority column displays the BACnet point priority for BACnet points.

Initials

The BACnet client option always displays BAC as the initials when an alarm is acknowledged. The correct user initials are displayed for alarms that are acknowledged by the Insight workstation, but alarms that are acknowledged by a foreign BACnet system display BAC. The initials SYS are displayed for alarms that do not require acknowledgements (similar to previous revisions of Insight software).

Alarm Acks

In BACnet, an object keeps an ack required flag for each state separately. The three states are To-OffNormal, To-Fault, and To-Normal. Each one of these states can require a separate acknowledgement. If the user acknowledges an item in the Insight alarm window, up to three acknowledgements are sent to the BACnet device (the BACstac keeps track of how many need to be sent). There is no means to acknowledge a single state. Conversely, if a third-party workstation acknowledges only one state when three states require acknowledgement, the Insight workstation will not display the alarm as acknowledged until all three states have been acknowledged.



Event Information and Alarm Summary

The Insight software supports the BACnet Get Event Information service (labeled getinformation). This service allows a BACnet field panel to be periodically interrogated for all of its alarms. If the BACnet field panel supports these services, the Insight workstation will learn and display any alarms for that device. It does this when it starts up and after a field panel returns from failure. This feature is optional on a field panel, so not all field panels will do this. APOGEE BACnet field panels support this service. The Event Information service replaces Alarm Summary. The Insight software still supports the Alarm Summary for compatibility with BACnet non-APOGEE field panels.

In addition to the above, the Insight workstation looks though its existing list of alarms and makes sure the alarms are current. For example, if Point A is in alarm and needs to be acknowledged, then the field panel that contains Point A fails and comes back later with Point A not in alarm and not needing to be acknowledged. The Insight alarm window will update with this new information. It will show the point's new status and show the point as acknowledged.

Unknown BACnet alarms

If an alarm displays for a point that is not known or has been deleted, then the name of the point will be the encoded name, such as BAC_1234_AO_3 (BACnet device instance number 1234, Analog Output Instance 3).

A registry key has been added to allow alarms for object types that are not supported by Insight as points to be displayed. The key is called ShowAlarmsForAllObjects and is under the client key.

If the key is set to 1, then the Insight workstation will display alarms for Life Safety Points, Life Safety Zones, Loops, etc.

If the key is 0 (the default), the Insight workstation will only show alarms for the standard point types (BI, BO, BV, AO, AI, AV, MI, MO, MV, EE).

BACnet Text Messages

In BACnet, confirmed/unconfirmed text messages can be sent to a device. If the Insight workstation receives any messages, they will be displayed in the BLN messages pane of the alarm window. The messages will also be logged in the system activity log.



Alarm Priority

The alarm priority found in a point's Notification Class object has a value from 0 to 255. This alarm priority is mapped to the six APOGEE alarm levels (Table 21).

Table 21. BACnet Alarm Priority mapping to APOGEE.

BACnet Notification Class Alarm Priority APOGEE Alarm Level Mapping

1 - 31 A1 (life safety)

32 - 63 A2 (property safety)

64 - 95 A3 (supervisory)

96 - 127 A4 (trouble)

128 - 191 A5 (high priority alarms)

192 - 255 A6 (low priority alarms)

The A1-A6 will be displayed for BACnet points in all applications that display priority. Table 22 shows example alarm displays.

Table 22. BACnet Alarm Displays.

BACnet alarm level Displayed as *A6*, for example. (Similar to APOGEE enhanced alarms.)

BACnet normal state Displayed as -N- regardless of the TO-NORMAL priority.

BACnet fault state Displayed as *F* regardless of the TO-FAULT priority.

Alarm Messages

BACnet supports sending an unlimited-sized text message with an alarm. The Insight workstation truncates the message to 200 characters. These messages are numbered and defined in the BACnet Field Panel Definition. Then, a message number can be entered in a point definition. (These are the same messages that are used for APOGEE enhanced alarms).

If the BACnet Field Panel Definition does not have any messages defined (only a message #0), one can be defined for the point in the Point Editor (Alarm Type, Alarm Properties), and the Insight alarm window will use that one. The message #0 triggers the Insight workstation to look in its message database.

APOGEE GO

All applications that display point priority will display BACnet priority for BACnet points.



Attribute Duplicator

The following BACnet properties can be copied by Attribute Duplicator if the source and destination point are APOGEE BACnet points:

Notification Class

Standard Alarm Message number

Event Enable Bits

Relinquish Default

BACNET Object Browser

The BACnet Object Browser is an Insight application that allows you to view and write to the BACnet objects and their properties using generic windows and dialog boxes. This application is accessed from the Tools menu in the System Profile application when you select either a BLN or a field panel in the tree.

Figure 26 shows an example of viewing the properties of a device object using the Object Browser. A navigation pane on the left side shows the hierarchy of the BACnet network and the device you are currently viewing. The right panel displays data about whatever item is selected in the tree. In Figure 26, a BACnet device is selected in the tree, so a device property view is seen on the right. If you were to select a point object in the tree, then you would see an object property view on the right. Error messages may display at the bottom of the screen, if applicable. Various filtering actions are also available within these screens.



Figure 26. Viewing Device Object Properties with the Object Browser.

BACnet Browser Features

Other features of the BACnet Browser include:

A View Options dialog box that lets you select what properties you want displayed by default (set in registry upon exiting).

A Tools menu that provides dialog boxes to:

Send Who-Is messages

Send Who-Has messages

Write properties of objects

Perform device communication control (as described in Chapter 10-BACnet Tools)

Re-Initialize a device

Import Points



There are 20 different view types. Each view can be printed and/or saved as a .csv file. These views appear in the View box at the top of the screen based on what is selected in the tree control and list control. For example, View Device Properties is displayed in the View box (Figure 26).

Most of the simple data types as well as the complex data types can be edited. The simple data types include strings, numbers, Boolean values, Bit strings, times, and date ranges. The complex data types include Weekly Schedules, Exception Schedules, Recipient Lists, Object Reference Lists, Action Lists and Calendars. (You must have configure access to the Browser to use Write Property.)

The browser has its own functional access level that can be set per user in the User Accounts application. There are two levels:

Read access–This lets you read/browse everything, but you cannot do write properties, import points, reinitialize a device or use device communication control commands.

Configure access–This lets you do everything.

Display and edit proprietary properties. (Only the simple data types can be edited–unsigned, float, Boolean, string, and signed.)

Display proprietary objects in their own folder. (The write property cannot be used.)

BACnet Browser Limitations

Limitations of the browser include:

The ability to only edit existing objects. You cannot create new objects or delete objects from the browser.

Some data types cannot be edited. The write property button will remain grey if you are on a property that cannot be written by the browser.

Point Commander

When a BACnet point is selected from the object selector or typed in, the Point Commander dialog box changes slightly. Instead of the non-BACnet priority buttons, you will see Set, Relinquish, and Advanced buttons and a drop-down list for BACnet priority (Figure 27).



Figure 27. Point Commander Dialog Box.

The drop-down list only contains priorities that the user has authorization to command (based on their user account setup).

The Advanced button displays the current Command Priority Array. It is enabled only for point types that can have a Command Priority Array. (AO, BO, MO, AV, BV, MV). Also, the Relinquish button is enabled only for points with Command Priority Arrays.

To command a point the user must select Set or Relinquish. If the point has a Command Priority Array, then the priority slot displayed will be commanded or relinquished. If the point does not have a Command Prioirty Array, the present value of the point will be written.

Out of Service will be enabled for third-party BACnet points and APOGEE input points only.



The command priority defaults to Manual Operator (the priority defined in Syspro as operator). If the user doesn’t have access to this level (defined in user accounts), it will default to the next lower priority (higher in number) that the user has access to. If the user does not have access to a lower priority, then the next higher one will be the default.

Reset Totalization is supported in BACnet. Only binary points can be totalized.

Alarm by command and ODSB are not supported in BACnet and will be grayed out.

Clicking on the Advanced button displays the BACnet Command Priority Array (Figure 28).

Figure 28. BACnet Command Priority Array.

The current values for all the Command Priority Array slots are displayed.

Users can relinquish any priority level that they have access to (from user account setup). Levels that the user does not have access to are grayed.

The actual relinquish happens after the point command (not when clicking OK to this command priority array dialog box).



Database Transfer

Progress Tab

In the Database Transfer dialog box, new BACnet databases have been added to the Progress tab. To make room, the four SSTO databases have been combined into one counter, and the TIU counter has been removed (there is only one TIU and only on pre-APOGEE panels). The four counters at the bottom have been added for BACnet (Figure 29).

Figure 29. Database Transfer Dialog Box.

Log Tab

Support has been added to display information as BACnet databases are uploaded and downloaded.



Upload Selected Dialog

New BACnet databases have been added to the upload selected database dialog box. You can selectively upload BACnet Schedules, Commands, Calendars, and Notification Classes.

Object Types

Two new object types will be uploaded and represented as points. The Trend log object will now get uploaded and represented as a virtual LDO. The Command object will be uploaded as a LENUM point. This is for third-party panels only.

Backup and Restore

Some BACnet devices will support a backup and restore of their database. Two buttons have been added to the toolbar (and menus) to perform these operations (Figure 30).

On a backup, the Insight workstation will store a single copy of the device database in the ATOM database. Any subsequent backups will overwrite the previous one. On a restore, Insight workstation will reinitialize the device and send down the last backup. The status of the backup and restore operation will be displayed in the log panel of the Database Transfer application. Users need configure access to database transfer to do a backup or a restore.

Some field panels, including those of Siemens Building Technologies, require a password. The user must enter this password in the BACnet Field Panel Definition dialog box in System Profile. For Siemens Building Technologies field panels, the password is the high account password.

Figure 30. Database Transfer Dialog Box for Backup/Restore.



Other Changes

Cloaked Panels will not appear in the panel list.

Dynamic Plotter

There are no changes to Dynamic Plotter other than it now supports BACnet points.

Event Log

BACnet loader messages and BACnet Text messages are logged in the System Activity log.

Event Printer

BACnet loader messages and BACnet Text messages are printed at the event printer.

RENO Notification

In order to send RENO notification when a BACnet point goes into alarm, the notification class must have checked “Acknowledgement required” for TO-OFFNORMAL and/or TO-NORMAL. BACnet points can have notifications on ALARM_PRIORITY 1 through 6.

PXC Compact Slope/Intercept

The PXC Compact field panel type was added to the slope intercept calculator. The same values as the MEC are used. In addition to the sensors that a MEC supports, the PXC Compact supports the following sensors: Nickel 1K RTD, Platinum 1K RTD 385, and Thermistor.

Program Editor

PPCL is supported in APOGEE BACnet field panels. The Save As dialog box has additional fields for BACnet (Figure 31).



Figure 31. Program Editor Save As Dialog Box.

If a BACnet field panel is selected, the fields in the BACnet Settings section become enabled. PPCL Command Priority is the priority at which the PPCL program commands points. The PPCL Command Priority defaults to the value defined through System Profile.

Report Builder/Reports

Display BACnet Priority

All reports that display point priority display the BACnet priority (BN01 through BN16). If no priority is present, NONE is displayed.

Reports

Point Definition Report

The Point Definition report displays the Object ID, Notification Class, Relinquish Default, and Event Enable Flags for BACnet points.

Panel Point Definition Report

The Panel Point Definition report displays the Object ID, Notification Class, Relinquish Default, and Event Enable Flags, and priority array for BACnet points.

Panel Configuration Report

The Panel Configuration report displays additional BACnet configuration data for APOGEE BACnet panels only.



Panel Display Report

The Panel Display report displays panel status information for BACnet BLNs. PXC Compact is also supported.

User Account Report

The User Account report displays a users functional access rights to the BACnet Browser. The users Command Priority Array access level is displayed.

System Profile Report

The System Profile report displays information for BACnet BLNs and Panels. PXC Compact is supported.

Trend Definition Report

The Trend Definition report shows the properties of a BACnet Trend Log object.

Panel Trend Definition Report

The Panel Trend Definition report shows the properties of a BACnet trend log object.

Trend Data Detail Report

The Trend Data Detail report shows data for BACnet Trend Log objects that have been collected. There are trend status markers for BACnet in addition to the dataloss marker we already available for the APOGEE Automation System. You can have the following entries:

Log Enabled–indicates the beginning of data collection.

Log Disabled–indicates the ceasing of data collection.

Log Purged–indicates a user purged all the data at the device by writing a 0 to the record count property.

Error–provides a BACnet error number. It indicates the device has problems collecting the data.

Time Changed–indicates the local time of the device was changed. It is the offset in seconds by which that the time changed.

Totalization Log Report

The Totalization Log report shows elapsed active runtime for BACnet binary points. It also shows the last reset time.



Scheduler


System Profile

Command Priority Array Strings

The BACnet Command Priority Array on the System menu displays the BACnet Command Priority Array dialog box (Error! Reference source not found.). This dialog box allows you to edit the long and short versions of the strings that are displayed for the different BACnet Command Priority levels. The short strings are used throughout most of the system. The long strings are available in the Point Commander. You can also select the default priorities for Insight applications.

BACnet Address Table

The BACnet Address Table selection on the System menu displays the BACnet Address Table dialog box (Error! Reference source not found.). This dialog box allows you to assign addresses to devices (for example, MS/TP devices) and objects that do not report their addresses when asked. This table is used by the field panel to resolve devices or objects that might appear in PPCL.

BLN Definition

The Building Level Network Definition dialog box for a BACnet BLN has changed slightly (Error! Reference source not found.). You can now specify the Instance Number for the Insight workstation, whereas, in previous revisions this could be done only in the registry.

Cloaking

The concept of cloaking has been added for BACnet panels. Clicking the Cloaked button in Status section of the BACnet Field Panel Definition dialog box, the panel is removed from the system profile tree. This allows you to hide devices that you do not want to appear at the Insight workstation and to keep device discovery from constantly re-adding the devices to a BLN.

Only third-party devices can be cloaked.

Selecting the Show Cloaked Panels item on the View menu in System Profile (Figure 32). displays the cloaked panels in the System Profile tree. This allows access to the definition dialog box where you can uncloak the panels, if desired. In this view, cloaked panels appear as an outline of a panel.



Figure 32. Show Cloaked Panels Item in System Profile.

FLN Devices

Device Instance range edit dialog boxes have been added to the TEC, LTEC, and UC definition dialog boxes. Figure 33 shows the TEC Definition dialog box.

Figure 33. TEC Definition Dialog Box.



The instance range fields are only enabled for BACnet field panels. These are the instance numbers that points on this FLN device will use.

Once the number of subpoints is saved, it cannot be changed. The TEC has to be deleted and re-added to change it.

The default base is displayed as –1. As soon as the field panel assigns a value, it will be uploaded to the Insight workstation and displayed. This cannot be set manually. Only the number of subpoints can be set when creating a device. The default and minimum value is 100.

Device Re-Initialization

If a BACnet device is selected in the tree and Coldstart/Re-Initialize on the Tools menu is selected, the BACnet Re-Initialize dialog box (Figure 34) displays to allow a warmstart or coldstart of the device.

Figure 34. BACnet Re-Initialize Dialog Box.

An Are you sure message box displays before the command is sent.

Some devices require a password. An error displays if left blank and the device requires a password. For APOGEE BACnet field panels, use the high account password.

Configure access to System Profile is required to issue this command.

Device Communication Control

If a BACnet device is selected in the tree and Device Communication Control on the Tools menu is selected, the BACnet Device Communication Control dialog box (Error! Reference source not found.) displays to allow users to send communication control commands to the panel. There are three commands: Enable, Disable, and Disable Initiation Only. The disable commands allow you to stop a device from communicating on the network for a period of time. For more details see Chapter 10-BACnet Tools.



Who-Is Diagnostic Tool

Clicking BACnet Custom Send Who-Is on the Tools menu displays the Who-Is Diagnostic Tool dialog box (Error! Reference source not found.). This tool allows users to send out Who-Is messages and view the I-am messages as they arrive. For more details, see Chapter 10-BACnet Tools.

Time-of-Day Scheduling

APOGEE BACnet field panels support the PPCL-based Time-of-Day scheduling.

Trend Editor

Trend Definitions

Users can create trend definitions for points only in APOGEE BACnet panels. The COV and Interval dialog boxes have a BACnet section that lists the properties of a Trend Log object.

Figure 35. Modify COV Definition Dialog Box.

User Accounts

Command Priority

In the Edit Insight Account dialog box (Figure 36), there is a section for BACnet Command Priority.



Figure 36. Edit Insight Account Dialog Box.

The Command Settings button displays the BACnet Command Priority Array dialog box (Figure 37).



Figure 37. BACnet Command Priority Array Dialog Box.

This allows selection of the BACnet priorities that the user is allowed to command or relinquish. These settings are used by the Point Commander to allow/disallow commanding and relinquishing certain priority levels.

Changes to these settings take effect next time the Insight workstation starts up. (Technically, the changes take effect the next time the Point Commander starts. However, once Point Commander is run, it really doesn’t shutdown until the Insight workstation is shutdown).

Insight Account Tab

The currently logged-in user account is selected by default. This is not specifically a BACnet related change, but is part of the Insight Release 3.7 application.

BLN Account TAB

BACnet BLNs appear in the BLN User Accounts tab. This allows assigning users to BACnet BLNs.



Figure 38. BLN User Accounts Dialog Box.

BACnet Export

BACnet Export, accessed from the Account menu, is a feature of the Insight BACnet server that enables populating the BACnet virtual network with non-BACnet APOGEE points in the Insight database server. The BACnet export dialog box has been enhanced to give a warning if the user exports points with COV limits twice the slope or smaller. These points will be displayed in an Export Results dialog box (Figure 39) and can be copied to the clipboard. This feature was added for Anthem support, which may lead to users exporting thousands of points. Too much COV traffic can be detrimental to a P2 (RS485) BLN.



Figure 39. Export Results Dialog Box.

Error handling has been improved. The Export Results dialog box will warn users when they forget to make the BACnet account or if no points are exported.


Chapter 7–BACnet Scheduling

Chapter 7 describes BACnet scheduling theory as it relates to scheduling in the APOGEE Building Automation System. It discusses the following topics:

BACnet Scheduling Theory

BACnet and Insight Scheduling

Setting Up BACnet Schedules

BACnet Scheduling Examples


BACnet Scheduling involves the interaction of the Scheduler object, the Calendar object and the objects (usually Command objects) whose properties are being commanded by the Scheduler object. The commanded objects’ properties are contained in the Scheduler object property called List_Of_Object_Property_References.

Figure 40 shows a simplification of this relationship. The BACnet Scheduler Object shows a partial list of its properties. The Schedule Object issues commands to the properties of objects in its List_Of_Object_Property_References according to its Weekly_Schedule property. The Weekly Schedule can be over-ridden by the Exception_Schedule property, which can be a fixed schedule or can be determined by the Calendar object. The exception schedule can be for special events, holidays, etc.

Figure 40. BACnet Scheduling Concept Drawing.



Schedule Object

The BACnet schedule object describes a periodic schedule that can occur during a range of dates that determines the values of one or more BACnet objects being controlled. The BACnet schedule object normally controls with a regular (Weekly) schedule, but also has an exception schedule list for holidays, special events etc. The exception function can integrate with the BACnet Calendar Object to ease programming of exception schedules that affect large numbers of schedule objects.

Schedules are divided into days, of which there are two types: normal days within a week and exception days. Both types of days can specify scheduling events for either the full day or portions of a day, and a priority mechanism defines which scheduled event is in control at any given time.

The current state of the Schedule object is represented by the value of its Present_Value property, which is normally calculated using the time/value pairs from the Weekly_Schedule and Exception_Schedule properties. A default value is used when no schedules are in effect.

Table 23. Properties of the Scheduler Object Type.

Property Identifier Property Data Type

Object_Identifier BACnetObjectIdentifier

Object_Name CharacterString

Object_Type BACnetObjectType

Present_Value Any

Description CharacterString

Effective_Period BACnetDateRange

Weekly_Schedule* BACnetARRAY[7]of BACnetDailySchedule

Exception_Schedule* BACnetARRAY[N]of BACnetSpecialEvent

Schedule_Default Any

List_Of_Object_Property_References List of BACnetDeviceObjectPropertyReference

Priority_For_Writing Unsigned(1..16)

Status_Flags BACnetStatusFlags

Reliability BACnetReliability

Out_Of_Service BOOLEAN

Profile_Name (NOT USED) CharacterString

* At least one of these properties is required.

BACnet Schedule Object Operation

The normal calculation of the Preset_Value of a schedule is:

Find the highest relative priority Exception Schedule that is in effect for the current day and whose current value is not NULL, and assign that value to the Present_Value property.



If the Present_Value was not assigned in the previous step, then evaluate the current value of the Weekly_Schedule array element for the current day and if that value is not NULL, assign it to the Present_Value property.

If the Present_Value was not assigned in the previous steps, then assign the value of the Schedule_Default property to the Present_Value property of the Preset_Value.

The current value of a schedule is the value associated with the latest time in either the Weekly Schedule or Exception Schedule that occurs on or before the current panel time. If no such element is found, then the current value for the schedule is considered to be NULL.

The calculation of the schedule value is such that it can be performed at any time and the correct value will result. In APOGEE BACnet field panels the calculation is performed:

At 00:00 each day.

Whenever the device resets.

Whenever properties that can affect the results are changed.

Whenever the time in the device changes by an amount that may have an effect on the calculation result.

At other times, as required, to maintain the correct value of the schedule through the normal passage of time.

The schedule value is equal to Schedule Default value at 00:00 of any given day unless there is an entry for 00:00 in effect for that day. If a scheduled activity begins on one day and ends on another day, an entry of 00:00 must be placed in the schedule that is in effect for the second day and for any subsequent days of the activity’s duration to ensure that the schedule value is calculated correctly.

Figure 41 shows a flowchart of the above descriptions of the calculations of the Present_Value of a Schedule object.



Figure 41. Flowchart of the Calculation of the Present_Value of a ScheduleObject.

Command Object

The Command object writes a set of values to a group of object properties in specified BACnet devices, based on the "action code" value that is written to its Present_Value.

The capability to write to remote devices is not required by the BACnet specification. So, a device that supports the Command object may not support writing outside that device. All BACnet devices, regardless of vendor, will accept commands from a Command object of a remote BACnet device.



The Command object is particularly useful in setting up BACnet schedules. For example, a particular zone of a building might have three states: UNOCCUPIED, WARMUP, and OCCUPIED. For each state, numerous objects' properties may need to be changed to specific values. For example, when unoccupied, the temperature setpoint might be 65°F and the lights might be off. When occupied, the setpoint might be 72°F and the lights turned on, etc. The Command object can command a mix of data types, whereas a Schedule object cannot.

Normally, a Command object is passive (its In_Process property is FALSE), indicating that the Command object is waiting for its Present_Value property to be written with a value. When the Present_Value is written, the In_Process property is set to TRUE, and the actions related to that particular Present_Value are executed. Any attempt to write to the Present_Value property through WriteProperty services while In_Process is TRUE is rejected.

The Action property of the Command object contains the Action Lists, which are indexed to the values that are written to the Present_Value property. Each value initiates its own action list in which the Command object writes a value to a property of an object in a particular BACnet Device. The writes occurs in the order that the Action List elements appear. If a list is empty, no action takes place, except that In_Process is returned to FALSE and All_Writes_Successful is set to TRUE.

The Command object does not guarantee that every write will be successful, and the Command object will NOT "roll back” successfully written properties to their previous values in the event that one or more writes fail to other properties.

If any of the writes fail for any reason, then the All_Writes_Successful property is set to FALSE and the Write_Successful flag for that specific Action is set to FALSE. If the Quit_On_Failure flag is TRUE for the failed Action, then the execution of the action list terminates prematurely and all subsequent Actions in the list shall have their Write_Successful flag set to FALSE. Otherwise, writing shall continue after each failure with the next element of the action list. Regardless of whether writes succeed or fail, All_Writes_Successful remains FALSE throughout the execution of an Action List.

If an individual write succeeds, then the Write_Successful flag for that specific Action is set to TRUE. If all the writes are successful, then the All_Writes_Successful property is set to TRUE. Once all the writes have been processed to completion, the In_Process property is set back to FALSE, and the Command object becomes passive again, waiting for another command. The Present_Value property will continue to indicate the action that the Command object has already taken.

At the moment that Present_Value is written to, In_Process is set to TRUE and All_Writes_Successful is set to FALSE. If after the list has been executed, all of the writes have succeeded, then All_Writes_Successful is set to TRUE at the same time that In_Process is set to FALSE. Therefore, while In_Process is TRUE, the value of All_Writes_Successful is not a valid indication of the current or previous operation.

It is important to note that the particular value that is written to the Present_Value property is not what triggers the action, but the act of writing itself. Thus, if the Present_Value property has the value 5 and it is again written with the value 5, then the 5th list of actions will be performed again.

Writing zero to the Present_Value of the command object causes no action to be taken and is the same as invoking an empty list of actions.



The Command object is a powerful function, but it can cause confusing or destructive side effects if improperly configured. Since the Command object can manipulate other objects' properties, it is possible that a Command object could be configured to command itself. In this case, the In_Process property acts as an interlock and protects the Command object from self-oscillation. However, it is also possible for a Command object to command another Command object that commands the first Command object and so on. The possibility exists for Command objects that command GROUP objects. In these cases of circular referencing, it is possible for confusing side effects to occur. When references occur to objects in other BACnet Devices, there is an increased possibility of time delays, which could cause oscillatory behavior between Command objects that are improperly configured in such a circular manner. Caution should be exercised when configuring Command objects that reference objects outside the BACnet device that contains them.

Table 24 summarizes the Command object and its properties.

Table 24. Properties of the Command Object.

PropertyIdentifier Property Data Type





Present_Value Unsigned

In_Process BOOLEAN

All_Writes_Successful BOOLEAN

Action BACnetARRAY[N] o fBACnetActionList

Action_Text BACnetARRAY[N] of CharacterString

Profile_Name CharacterString

The Object Identifier property, which contains the instance number, is a numeric code that must be unique within the BACnet Device that maintains it. The Object type property has the value COMMAND.

The Action Lists are indexed by the value that is written to the Present_Value property. A given list may be empty, in which case no action takes place, except that In_Process is returned to FALSE and All_Writes_Successful is set to TRUE. If the list is not empty, then for each action in the list, the Command object writes a particular value to a particular property of a particular object in a particular BACnet Device based on the specifications in the Action. Each write occurs in the order that the Action List elements appear.

Each Action specifies a single value be written to a single property of a single object. Actions have nine components. Table 25 lists these components and their data types.



Table 25. Action Property Components and Data types.

Component Data Type

Device_Identifier BACnetObjectIdentifier (Optional)


Property_Identifier BACnetPropertyIdentifier

Property_Array_Index Unsigned (Conditional)

Property_Value Any

Priority Unsigned (1..16) (Conditional)

Post_Delay Unsigned (Optional)

Quit_On_Failure BOOLEAN

Write_Successful BOOLEAN

When the Property_Identifier (Property ID) refers to an array property, then the Property_Array_Index value is used to specify the index within the array of the property to be written.

After each write, whether successful or not, if the Post_Delay is present, it shall represent a delay in seconds before the execution of the next write or the completion of all writing and the setting of In_Process to FALSE.

Calendar Object

The BACnet Calendar Object is a list of date entries from which action can be initiated. The Calendar Object’s Present Value is a Boolean TRUE on any date that is defined by its Date List. On other dates the Calendar Object’s Present Value is FALSE.

In the APOGEE BACnet field panel, the Present Value of the Calendar Object is set includes:

After 00:00 each day.

Whenever the device resets.

Whenever properties that can affect the results are changed.

Whenever the time in the device changes by an amount that may have an affect on the calculation result.

At other times, as required, to maintain the correct value of the calendar through the normal passage of time.

Table 26 lists the properties of the Calendar Object.



Table 26. Properties of the Calendar Object.

Property Identifier Property Data Type





Present_Value BOOLEAN

Date_List List of BACnetCalendarEntry

Profile_Name CharacterString (not used)


BACnet replaces the APOGEE Scheduling application as shown in Table 27.

Table 27. BACnet Replacements for APOGEE Functions.

APOGEE: Replaced by BACnet:

Weekly Schedule (allows varied start & end times for all zones and events)

Schedule Object’s Weekly Schedule (must be the same start and end times for all zones and events within this Schedule)

Mode Schedule Schedule Object together with Command Object

Special Assignment

(Replacement Day)

(Day Shift)

Override

Schedule Object’s Exception Schedule

Zone Command Object

Command Table (within a Zone) Command Object’s Action List

Calendar (that is shared as global data on the BLN)

Calendar Object

Start Stop Time Optimization (SSTO) SSTO in PPCL

Insight software supports viewing, creating, deleting, and editing Schedules, Zones, and Events.

APOGEE Go supports scheduling Zones, Events, and Reports that already exist in Insight.

Insight software supports viewing, creating, deleting, and editing of schedules, calendars, and command objects.

BACnet Object Browser supports viewing schedules, calendars, and command objects.

APOGEE Go supports viewing, creating, deleting, and editing of schedules and calendars.



Event Scheduling

BACnet objects cannot be included within an Insight Event. The closest method for duplicating an Event with BACnet is to include the object IDs in the Action List of a BACnet Command Object. The object IDs can be Command objects themselves and can be considered similar to APOGEE zones.

Start Stop Time Optimization (SSTO)

Firmware Revision 2.7 offers no integration of BACnet Scheduling to the APOGEE or pre-APOGEE SSTO algorithms except to command the Present_Value of an object. To implement SSTO in field panels with this firmware, either use the APOGEE SSTO implemented in the Insight Soft Controller option, or pre-APOGEE PPCL-based Time-Of-Day Start Stop Optimization.

BACnet Device Database Storage

Schedule and Calendar objects for Siemens BACnet panels are stored in the Insight database. So, these objects can be edited even if the Insight workstation is not communicating with the panel (editing may be performed online or offline).

Schedule and Calendar objects for third-party BACnet devices are stored in the third-party devices only. Therefore, these objects can be edited only when the Insight workstation is communicating with the device (editing must be performed online only).

Schedule Object Properties that Can be Commanded

Although the BACnet Schedule specification supports commanding object properties of any type, the Siemens Building Technologies BACnet field panel implementation is limited to:

Unsigned - intended for commanding the value of a Command Object.

Real - intended for Analog Output points.

Enumerated - intended for commanding Binary Output points.

Boolean - intended for enabling/disabling Trend Log objects.

In most cases, the property written is limited to the Present_Value property.

1. Object properties that are Arrays of the above simple data types (unsigned, real,

enumerated and Boolean) are not supported by Siemens Building Technologies BACnet field panels.

2. The capability to write to remote devices is not required by the BACnet specification, but the Siemens Building Technologies’ BACnet field panel supports commanding to outside devices. All BACnet devices, regardless of vendor, will accept commands from a Siemens Building Technologies BACnet field panel.




The following examples illustrate how Scheduling works in an APOGEE field panel implementing the BACnet 2004 specification.

BACnet Scheduling Example 1

Figure 42 is an example of a BACnet schedule. This simple example shows the basic elements of BACnet scheduling.

The Schedule object name is season-based because it relates to its Effective Period property. The Description is geographic so a user does not have to drill down to each of the Object Property References to determine what zones are controlled by this Schedule object. If every building on the campus had a different Weekly Schedule, then it would probably be appropriate to include the building name in the Schedule Name for quicker access by the user.



Figure 42. BACnet Scheduling Example.

The Weekly Schedule (Figure 43) starts at 00:00:00 and causes the Night Cooling Action to occur, otherwise the Schedule Default (0) will take over at midnight and no action will occur until 6:00:00, when Cool down begins. The Occupied (cooling) action occurs at 8:00:00 and ends at 18:00:00 when Night Cooling reinstates.



Figure 43. Example 1 Weekly Schedule for Night Cooling.

The Exception Schedule comes from the Calendar object named Holiday Calendar. This requires that the user update only this one Calendar object each year with the new holiday dates. The Date List shows that fixed dates are entered for most of the holidays while Date Ranges are entered for the Thanksgiving and Christmas holidays.

The List of Object Property References shows the three Command objects being commanded by the Schedule object. Each Command object represents a building. The Name and Description are use to detail how the Command object is programmed and save the user some time viewing each. The Action List of each Command object includes the supply fan object. Obviously, there is no Start Stop Time Optimization implemented. If there was SSTO, the supply fan would be controlled by SSTO PPCL as explained elsewhere in this section.


The weekly schedule is: 8:00=OCC and 17:00=UNOCC

It is desired to have a week in which everyone leaves early at 15:00.

To do this, set up an exception schedule that defines the week (for example, 24 December 2005, 02 January 2006) and has one time entry (15:00=UNOCC).





It is desired to have a week in which everyone arrives later (9:00) and leaves early (15:00).

To do this, set up an exception schedule that defines the week (for example, 24 December 2005, 02 January 2006) and has three entries (UNOCC with any time between 00:00:00 and 7:59:59, and 9:00=OCC, and 15:00=UNOCC).



It is desired to have a week in which everyone arrives early (7:00), but leaves at the time in the weekly schedule (leaving time may vary slightly from day-to-day).

To do this, set up an exception schedule with two entries (7:00=OCC, and NULL with any time value between 8:00:01 and earliest possible UNOCC time in the weekly schedule).



BACnet Scheduling Example 5 On a university campus, BACnet scheduling can be used to ring the bells on each hour and 50 minutes after each hour, 24 hours a day. The bells should ring for four seconds. To do this, create a BACnet Schedule object and BACnet Command Objects as follows: Schedule Object Schedule Name:

Campus Bells Description:

Class Bells – All Buildings Effective Period:

Start: August <last><any>Monday End: May <last><any>Friday

Weekly Schedule: *:00:00 2 *:00:04 1 *:50:00 2 *:50:04 1

Schedule Default: 1

List of Object Property References: Lecture Hall 1 Bells Lecture Hall 2 Bells Lecture Hall 3 Bells Lecture Hall 4 Bells Classroom Hall 1 Classroom Hall 2 Classroom Hall 3 Classroom Hall 4 Outdoor Annunciator

Command Object (one of many) Name:

Lecture Hall 1 Bells Description:

Class Bells – All Floors Action Index:

1 Bells OFF 2 Bells ON

Action List (Bells OFF): First Floor Bells OFF Second Floor Bells OFF

Action List (Bells ON): First Floor Bells ON Second Floor Bells ON

If 24 hour operation is not desired, a separate entry for each hour can be entered in the Weekly Schedule. For example:

08:00:00 2 08:00:04 1 08:50:00 2 08:50:04 1 09:00:00 2 09:00:04 1 09:50:00 2 09:50:04 1 Etc.


Chapter 8–BACnet Alarming

Chapter 8 describes BACnet alarming theory, how it relates to the APOGEE Building Automation System, and how to set up alarming in APOGEE. It discusses the following topics:

BACnet Alarming Theory

BACnet and APOGEE

Setting Up BACnet Alarming

BACnet Alarming Example


BACnet Alarming involves communications related to events. An event is a change in value of a property of a source object or a change in the internal status of a source object. An example of a change in value of a property is the change in the Present_Value of an Analog Input object. The BACnet specification provides three mechanisms for managing property-value-change events: change of value reporting, algorithmic change reporting, and intrinsic reporting.

Intrinsic reporting is the BACnet mechanism supported by the Siemens Building Technologies APOGEE Automation System for managing alarms and events. For complete details on intrinsic reporting, see Intrinsic Reporting.

Change Of Value (COV) Reporting

Change of value (COV) reporting allows an event (alarm) to be generated when a property of a BACnet object changes in value by an amount in the object’s COV_Increment property. If an object supports the COV_Period property, COV notifications are issued at the interval specified by COV_Period, in addition to the notifications initiated by the change of value. If COV_Period is zero, the periodic notifications are not issued.

Like many other BACnet features, COV reporting is optional, based on the choice of the manufacturer of the BACnet device. The manufacturer is also allowed flexibility in how COV reporting is implemented. It can be implemented on standard BACnet objects and/or non-standard objects. A manufacturer may use the COV_Increment property or choose to use other criteria for COV generation.

For more information about BACnet Change of Value reporting, see Section 31.1 of the ANSI/ASHRAE Standard 135-2004 (or newer) and the documentation provided by the manufacturer of the BACnet device (field panel) providing COV reporting.



Algorithmic Change Reporting

Algorithmic change reporting uses a source point (Reference Object), defined by an Event Enrollment object, to generate alarm or event notification. Then, a property of the point (its referenced property) is applied to a standard algorithm (Event Type) to determine if there should be a change report. Occurrences of change are then reported to destinations based on a Notification Class object. For example, the changes of the value of a property of an object may be programmed to trigger event notifications to be sent to one or more workstations.

The following event type algorithms are specified in the BACnet standard:

Buffer_ready

Change_of_bitstring

Change_of_life_safety

Change_of_state

Change_of_value

Command_failure

Floating_limit

Out_of_range

Unsigned_range

For more information about BACnet Algorithmic Change Reporting, see Section 31.3 of the ANSI/ASHRAE Standard 135-2004 (or newer) and the documentation provided by the manufacturer of the BACnet device (field panel) providing the Algorithmic Change Reporting. The Insight application with the BACnet Option can receive Algorithmic Change Reporting events, but the APOGEE field panels do not support Algorithmic Change reporting.

Intrinsic Reporting

Intrinsic reporting is the BACnet mechanism supported by the Siemens Building Technologies’ APOGEE Automation System for managing alarms and events.

In Intrinsic reporting, the logic for creating the alarm is contained within the source object of the alarm. A change of value of a specific property of the object, or changes of status internal to the object, triggers an event notification.

Figure 44 shows the relationship of an Analog Input Object and the Notification Class object in the intrinsic reporting process. An intrinsic alarm can be generated within the Analog Input Object if the Present_Value property makes a transition to outside of the range between High_Limit and Low_Limit properties for longer than Time_Delay property and the new transition is enabled in Event_Enable and Limit_Enable properties. The alarm is sent to destinations as defined in the Notification Class object. For examples of the operation of intrinsic reporting in BACnet objects, see Table 30.



Figure 44. BACnet Intrinsic Reporting.

The Notify_Type property of an event-initiating object identifies whether the occurrence is an alarm or an event. In BACnet, the only distinction between alarms and all other events is that alarms are reported by a BACnet service called GetAlarmSummary, while all other events are not.

Notification Class

A Notification Class object directs the alarm or event notifications to specific destinations, such as workstations. The destinations are defined in the Recipient_List property. The Notification Class object also defines the priorities of the event-notification messages, and whether acknowledgments are required. Multiple alarm or event-initiating objects may reference the same Notification Class object in a device. Internal status change alarms usually generate diagnostic notifications. Table 28 describes the Notification Class object’s properties.

Table 28. Notification Class Object’s Properties’ Description.

Property Description

Object_Identifier Must be unique within its BACnet Device. This is a combination of the Object_Type and the Instance Number (Notification Class number).

Object_Name Must be unique within its BACnet Device and is restricted to printable characters.

Object_Type Is always NOTIFICATION_CLASS.

Description Can be any printable character and need not be unique.



Notification_Class. This object’s instance number.

Priority An array of three integers, used for event notifications for TO-OFFNORMAL, TO-FAULT, and TO-NORMAL transitions, respectively. Priorities range from 0 - 255 with a lower number indicating a higher priority. Priority and the Network Priority are associated as defined in Table 31.

Ack_Required Conveys three separate flags that represent whether an acknowledgment is required in notifications generated for the following transitions, respectively:

TO-OFFNORMAL

TO-FAULT

TO-NORMAL

Recipient_List A list of BACnet destinations to which notifications are sent upon an occurrence of an event. See Table 29.

Profile_Name A vendor code identifying the vendor and its name for a set of additional properties, behavior, and/or requirements for this object beyond those of the BACnet specification. An optional property.

Recipient List (Destinations)

It is often necessary for event notifications to be sent to multiple destinations or to different destinations based on the time of day or day of week. For example, HVAC alarms may be sent to the HVAC manager during regular hours and to the guard station after hours.

Within each destination (Recipient_List) record is a set of Valid Days of the week (Monday through Sunday) and a From Time and To Time, during which the destination is sent a notification. Also specified is the applicable event transition(s) (TO-OFFNORMAL, TO-FAULT, or TO-NORMAL) for which the destination is sent a notification. See Table 29.

For a specific event transition (TO-OFFNORMAL, TO-FAULT, or TO-NORMAL) to reach a recipient, that transition choice has to be selected BOTH in the source object AND in the destination (recipient) record.



Table 29. Components of a BACnet Destination (Recipient List).

Parameter Description

Valid Days The set of days of the week on which this destination may be used between From Time and To Time.

From Time,

To Time

The window of time (inclusive) during which the destination is viable on the days of the week Valid Days.

Recipient The destination device(s) to receive notifications.

Process Identifier The handle of a process within the recipient device that is to receive the event notification.

Issue Confirmed Notifications

(TRUE) if confirmed notifications are to be sent and (FALSE) if unconfirmed notifications are to be sent.

Transitions A set of three flags that indicate those transitions {TO-OFFNORMAL, TO-FAULT, TO-NORMAL} for which this recipient is suitable.

Transitions and Event States

Event-initiating objects identify their "state" from moment to moment as one of any number of possibly unique event states. Notifications are triggered by the "transition" from one event state to another. Alarm and event transitions are broadly classified into one of three possible groups:

TO-FAULT–Transition to a malfunction, nearly always representing a failure within the automation system itself.

TO-OFFNORMAL–Transition to a condition within the system that is not normal and meets a specific event criteria (Table 30), but is not a fault.

TO-NORMAL–Transition to a condition that is anything else.



Different object types use different standard criteria and different event types for determining that an event has occurred. Table 30 summarizes the standard objects that may provide intrinsic event notification and their event types.

Table 30. Standard Objects That May Support Intrinsic Reporting.

Object Type Criteria Event Type

Binary Input, Binary Value, Multi-state Input* Multi-state Value*

If Present_Value changes to a new state for longer than Time_Delay AND the new transition is enabled in Event_Enable.

The Alarm_Value property specifies which of the two Present_Value states are interpreted as OFF_NORMAL. The opposing state is NORMAL. Transitions to either or both states may generate notifications if the corresponding flags are set in Event_Enable.

CHANGE_OF_STATE

Binary Output, Multi-state Output

If Present_Value differs from Feedback_Value for longer than Time_Delay AND the new transition is enabled in Event_Enable

COMMAND_FAILURE

Loop If the absolute difference between Setpoint and Controlled_Variable_Value exceeds Error_Limit for longer than Time_Delay AND the new transition is enabled in Event_Enable

FLOATING_LIMIT

Analog Input, Analog Output, Analog Value, Pulse Converter

If Present_Value exceeds range between High_Limit and Low_Limit for longer than Time_Delay AND the new transition is enabled in Event_Enable and Limit_Enable, OR Present_Value returns within the High_Limit - Deadband to Low_Limit + Deadband range for longer than Time_Delay AND the new transition is enabled in Event_Enable and Limit_Enable

OUT_OF_RANGE

Trend Log If Event_State is NORMAL state and Records_Since_Notification is equal to Notification_Threshold

BUFFER_READY

Life Safety Point* Life Safety Zone*

If Present_Value changes to become equal to one of the values in the Life_Safety_Alarm_Values list AND remains equal to a value within the Life_Safety_Alarm_Values list for longer than Time_Delay AND the new transition is enabled in Event-Enable OR If Present_Value changes to become equal to one of the values in the Alarm_Values list AND remains equal to a value within the Alarm_Values list for longer than Time_Delay AND the new transition is enabled in Event-Enable OR Mode changes

CHANGE_OF_LIFE_SAFETY



Object Type Criteria Event Type

Accumulator If Pulse_Rate exceeds range from Low_Limit through High_Limit for longer than Time_Delay AND the new transition is enabled in Event_Enable and Limit_Enable, OR Pulse_Rate returns to range from Low_Limit through High_Limit for longer than Time_Delay AND the new transition is enabled in Event_Enable and Limit_Enable

UNSIGNED_RANGE

* For Multi-state Input, Multi-state Value, Life Safety Point, and Life Safety Zone objects, the Alarm_Values property lists each of the possible Present_Value states that are interpreted as OFFNORMAL. The Fault_Values property lists each of the possible Present_Value states that are interpreted as FAULT. All other Present_Value states are interpreted as NORMAL. Transitions to any of the states may generate notifications if the corresponding flags are set in Event_Enable. For Life Safety Zone and Life Safety Point objects, the Life_Safety_Alarm_Values property lists each of the possible Present_Value states that are interpreted as LIFE_SAFETY_ALARM.

Alarm Acknowledgement

In some systems a device may need to know that an operator has seen and responded to the alarm notification. The BACnet object keeps track of the acknowledgement of each of the three event transitions separately. Each one of these states can require a separate acknowledgement. A Time Stamp' is used to identify the event notification that is being acknowledged.

Alarm and Event Priority

Alarms and events traversing the BACnet network need prioritization to assure that important information reaches its destination and is acted upon quickly. Priorities may be assigned to TO-OFFNORMAL, TO-FAULT, and TO-NORMAL events individually within a notification class. To assure alarm prioritization at the network level, the Network Priority is set as a function of the alarm and event priority as defined in Table 31.

Table 31. Alarm and Event Priority - Network Priority Association.

Alarm and Event Priority Network Priority

00 through 63 Life Safety message

64 through 127 Critical Equipment message

128 through 191 Urgent message

192 through 255 Normal message

As with the other reporting mechanisms, the manufacturer of a BACnet device can choose whether to have proprietary objects support intrinsic reporting.



BACnet and APOGEE

The Siemens Building Technologies’ BACnet field panel supports the BACnet specification’s Intrinsic Alarming on points, replacing the Insight’s standard alarm and enhanced alarm applications. BACnet intrinsic alarms, although closely resembling APOGEE standard alarms, include Notification Class Objects, which are similar to the APOGEE model for alarm destinations (also known as categories). For APOGEE BACnet field panels, an alarm message number can also be defined in the point definition. Figure 45 shows an example of the APOGEE implementation of BACnet Alarming from the perspective of a system point (BACnet Analog Input object).

Figure 45. APOGEE Implementation of BACnet Alarming.

Table 32 shows a quick comparison of BACnet Alarming and APOGEE Alarming.

Table 32. Comparison of BACnet and APOGEE Alarming.

APOGEE BACnet

APOGEE Points with Standard Alarms displayed at Destination Zero.

BACnet Objects with Intrinsic Alarms displayed at any Notification Class.

Alarm destinations are a shared global database. Notification classes are a downloadable database per panel.

Alarms are sent to the mass storage device (Insight) by default if a destination is unknown.

Alarms are only sent to devices in the Notification Class recipient list–even the device in which the alarm originated.

Alarm Enable/Disable

Operator-initiated and PPCL-initiated alarm enable/disable are not available for BACnet.


BACnet and APOGEE

Floating Alarm Limits

Floating Alarms (in which the alarm setpoint moves with the value of another point) are not available with the APOGEE BACnet solution. Use PPCL to create floating alarms. See the Creating Multiple Alarm Levels For Analog Points section of BACnet Modular Building Controller Power Open Processor Start-up Procedures (145-024) and BACnet Modular Equipment Controller (MEC) and Point Expansion Module (PXM) Start-up Procedures (145-025).

System Messages

Some examples of APOGEE Automation System events are PPCL run-time errors and Logon/Logoff messages. The APOGEE Automation System messages are available to third-party devices delivered using unconfirmed text message service..

Initials

When alarms are acknowledged by an Insight operator, the correct user initials will be displayed. Alarms that are acknowledged by a third-party system will display BAC at the Insight workstation. The initials SYS will be displayed at the Insight workstation for alarms that do not require acknowledgements.

Alarm Acknowledgements

In BACnet, each one of the three state transitions (To-OffNormal, To-Fault, and To-Normal) can require a separate acknowledgement. If an operator acknowledges an item in the alarm window from the Insight workstation, it will send up to three acknowledgements to the BACnet device (software keeps track of how many acknowledgements to send). A means to acknowledge a single transition is not provided. Conversely, if a third-party workstation acknowledges only one state, when three states require acknowledgement, the Insight application will not display the alarm as acknowledged until all three states have been acknowledged.

Get Event Information vs. Alarm Summary

The BACnet Get Event Information service (labeled geteventinformation) allows a BACnet device (field panel) to be periodically asked for all of its alarms. The Insight BACnet option supports this service. If a BACnet device also supports this service, the Insight application will learn this and display any alarms for the device. Insight asks for the alarms when the Insight application starts up and after a device returns from failure or being unconnected. This is a feature of APOGEE field panels, but not all third-party devices do this.

Additionally, the Insight workstation checks its existing list of alarms and makes sure they are up to date. For example, suppose Point A is in alarm and needs to be acknowledged. Then, the device that contains Point A fails but comes back later with Point A not in alarm and not needing to be acknowledged. The Insight alarm window will update with this new information. It will show the point’s new status and show the point as acknowledged.



APOGEE BACnet field panels support the get event information service as a replacement for the Alarm Summary function. The Insight BACnet Option still supports the Alarm Summary for devices that support only Get Alarm Summary function (for example, old BACnet field panels).

Unknown BACnet Alarms

If an alarm comes in for a point that is not known or has been deleted, then the name of the point will be the encoded name, such as, BAC_1234_AO_3 (BACnet device instance number 1234, Analog Output Instance 3).

Life Safety Alarms

Only alarms for the following standard point types are displayed:

Binary Input

Binary Output

Binary Virtual

Analog Output

Analog Input

Analog Virtual

Multi-state Input

Multi-state Output

Multi-state Virtual

A registry key has been added to allow alarms for object types that are not supported by the Insight application as points to be displayed. The key is called ShowAlarmsForAllObjects and is under the client key.

If the key is set to 1, then the Insight application displays alarms for Life Safety Points, Life Safety Zones, Loops, etc.

If the key is 0 (the default), the Insight application only shows alarms for the standard point types (BI, BO, BV, AO, AI, AV, MI, MO, MV, EE).

BACnet Text Messages

In BACnet, confirmed/unconfirmed text messages can be sent to a device. If the Insight application receives any messages, they will be displayed in the BLN messages pane of the alarm window. The messages will also be logged in the system activity log.

Alarm Priority

The alarm priority found in a point’s Notification Class object has a value from 0 to 255. This alarm priority is mapped to the six APOGEE alarm levels (Table 33).


BACnet and APOGEE

Table 33. BACnet Alarm Priority mapping to APOGEE.

BACnet Notification Class Alarm Priority APOGEE Alarm Level mapping

1 - 31 A1 (life safety)

32 - 63 A2 (property safety)

64 - 95 A3 (supervisory)

96 - 127 A4 (trouble)

128 - 191 A5 (high priority alarms)

192 - 255 A6 (low priority alarms)

The A1-A6 will be displayed for BACnet points in all applications that display priority. Examples of alarm displays (Table 34).

Table 34. BACnet Alarm Displays.

BACnet alarm level Displayed as *A6*, for example. (Similar to APOGEE enhanced alarms)

BACnet normal state Displayed as –N– regardless of the TO-NORMAL priority

BACnet fault state Displayed as *F* regardless of the TO-FAULT priority.

Alarm Messages

BACnet supports sending an unlimited-sized text message with an alarm. Insight truncates the message to 200 characters. These messages are numbered and defined in the BACnet Field Panel Definition. Then, a message number can be entered in a point definition. (These are the same messages that are used for APOGEE enhanced alarms).

If the BACnet Field Panel Definition does not have any messages defined (only a message #0), one can be defined for the point in the Point Editor (Alarm Type, Alarm Properties), and the Insight alarm window will use that one. The message #0 triggers Insight to look in its message database.

BACnet Browser

Point Objects

When viewing point objects with the BACnet Browser, each point type has properties associated with intrinsic alarming. If the point is configured for alarms, the properties are readable as a group. If the point is NOT alarmable, the properties do not appear.

The Event_Enable property displays a point’s ability to send alarms as follows:

All three bits are TRUE if the point is alarmable AND alarms are enabled.

All three bits are FALSE if the point is alarmable AND alarms are disabled.

There may be a mix of TRUE and FALSE.



The Event_Enable property may be written for:

Alarm enable–all flags set to TRUE.

Alarm disable–all flags set to FALSE.

Point Add–mix and match of TRUE and FALSE.

Point Modify–mix and match of TRUE and FALSE.

The Event_Enable property may be edited within the BACnet Browser. Any change to the Event_Enable bits will refresh the Browser display and will trigger a point upload, but will not cause an annunciation.

RENO Notification

RENO notifications can be sent from BACnet points. BACnet points can have RENO notifications on Alarm Priorities 1 through 6. To send a RENO notification when a BACnet point goes into alarm, the appropriate Ack required choice for the desired transition must be checked in the BACnet Notification Class dialog box.

RENO notification examples:

For a RENO notification of a TO-OFFNORMAL transition, Ack required for To Off-Normal transitions must be checked.

For a RENO notification of a TO-FAULT transition, Ack required for To Fault transitions must be checked.

It is suggested that ALL of the “Ack required…” check boxes be checked when RENO notification is required.

APOGEE GO

APOGEE GO can display BACnet alarms like any other APOGEE alarms. However, it does not provide any capability for setting up alarm functionality. For example, Notification Class and Alarm Message dialog boxes are not accessible.


Figure 46 shows an example of applying BACnet Alarming to a VAV air handling system. The AHU has the following components:

Mixed air dampers

Cooling coil

Low temperature detector switch (LTD)

Differential pressure flow-proofing switch (DI for L2SL)

Fan with relay requiring a latched contact (DO for L2SL)

Supply air temperature sensor (SAT)



Supply static pressure sensor (SSP)

Figure 46. Air Handling Unit for BACnet Example.

The requirement is to apply alarms to the L2SL, LTD, SAT, and SSP points.

L2SL Point

A supply fan alarm must occur if the differential pressure proofing switch does not close 60 seconds after the fan has been commanded to the ON state. In the Point Editor, a L2SL point is created (Figure 47). BACNet-specific entries are made as follows:

Addresses–The address of the digital output controlling the fan relay (0.0.25), the address of the digital input proofing switch (0.0.1), and the value of 60 for the Proof Delay seconds are entered.

BACnet Settings–A -1 is entered for auto assignment of the point’s Instance Number and 1 is entered for Notification Class. For details, see Figure 54.

Relinquish Default is set to OFF.

Alarm Type–Standard Alarms is selected. The Alarm Properties button does not need to be clicked because there are no entries to be made in this point’s Standard Alarm Setup dialog box.

Alarm Characteristics–This fan system’s operation is important, so alarms are to annunciate on all three types of transitions. Alarm Message #2 is to appear in the alarm banner. For details, see Figure 54.



Figure 47. Supply Fan L2SL Point Example.

LTD Point

A low temperature alarm must occur if the low temperature detector switch (“freezestat”) trips. In the Point Editor, a LDI point is created as shown in Figure 48. BACNet-specific entries are made as follows:

Address–The address of the physical digital input (0.0.2), is entered.


Relinquish Default is set to OFF


Alarm Characteristics–The low temperature device has to be manually reset at the device, so it is decided that it is not necessary to annunciate transitions to Normal. Alarm Message #3 is to appear in the alarm banner. For details, see Figure 54.



Figure 48. Low Temperature Device Digital Input Point Example.

SAT Point

An alarm must occur if the supply air temperature is too low or too high. In the Point Editor, a LAI point is created (Figure 49). BACNet-specific entries are made as follows:

Address–The address of the physical analog input (0.0.17) of the BACnet device, is entered.


Relinquish Default –Is set to 55°F.

Alarm Type–Standard Alarms is selected. The Alarm Properties button is clicked because there is to be a private message entered in this point’s Standard Alarm Setup dialog box (Figure 50).



Alarm Characteristics–High and Low Alarm Limits are set to 65 and 45°F, respectively (10 degrees above and below the setpoint of 55°F). This temperature is to be monitored closely, so alarms are to annunciate on all three types of transitions. Alarm Message is set to #0 so that a Private Message, entered in the Standard Alarm Setup dialog box (Figure 50), will be available from the Insight alarm banner. Right click on the banner and select View Alarm Message (Figure 51).

Figure 49. Supply Air Temperature Analog Input Point Example.



Figure 50. Standard Alarm Setup Dialog Box for SAT Point Example.

Figure 51. Alarm Banner and Message Box with Private Message Text.



SSP Point

An alarm must occur if the supply static pressure is too low or too high. In the Point Editor, a LAI point is created as shown in Figure 52. BACNet-specific entries are made as follows:

Address–The address of the physical analog input (0.0.18) of the BACnet device, is entered.


Relinquish Default –Is set to 0 inches of H2O.


Alarm Characteristics–The fan static pressure is important, so alarms are to annunciate on all three types of transitions. Alarm Message #4 is to appear in the alarm banner. For details, see Figure 54.

Figure 52. Supply Air Static Pressure Analog Input Point Example.



Notification Class

The BACnet points in this air handling unit all use Notification Class Instance #1. The Notification Class is set up in the Notification Classes dialog box (Figure 53). Notification Class 1, named HVAC Maintenance, has the following priorities:

To Off-Normal–160

To Fault–130

To Normal–200

To Fault has the highest priority because it has the lowest number. An acknowledgement is required for all transitions that are annunciated.

The Recipient List for Notification Class #1 is set up such that Insight workstation Device 15001, the HVAC Maintenance workstation, is the recipient of all transitions during regular working hours (Monday through Friday from 6 A.M. to 6 P.M.). At other times, the Security Guard workstation is the recipient of all transitions. This is accomplished by the first three line entries in the Recipient List.

Figure 53. Notification Class Dialog Box for Example.



Alarm Message Definition

Three points on the air handling unit have Alarm Message Numbers assigned:

Supply Air Fan (SAF)–Alarm Msg #2

Low Temperature Detector (LTD)–Alarm Meg#3

Supply Static Pressure (SSP)–Alarm Msg#4

These messages are defined in the Alarm Message Definition dialog box (Figure 54) this dialog box is accessed by clicking the Alarm Messages button on the BACnet Field Panel dialog box in the System Profile application.

Figure 54. Alarm Message Definition Dialog Box for Example.

New messages are added by clicking the New button which opens the New Alarm Message dialog box (Figure 55).



Figure 55. New Alarm Message Dialog Box for Example.

Figure 56 and Figure 57 show examples of messages.

Figure 56. Alarm Message #3 Definition Dialog Box for Example.

Figure 57. Alarm Message #4 Definition Dialog Box for Example.


Chapter 9–BACnet Trending

Chapter 9 describes BACnet trending theory and trending in an APOGEE Building Automation System. It discusses the following topics:

BACnet Trending Theory

BACnet Trending in APOGEE


The Trend Log object, the heart of BACnet trending, monitors a property of an object. In APOGEE BACnet, this property is the Present_Value of the point-like object specified in the Log_DeviceObjectPropery (Figure 58). When predefined conditions are met, the Trend Log object writes the following to its Log_Buffer property for subsequent retrieval: the Present_Value, a time stamp, and certain status flags. Errors that prevent the acquisition of the data, as well as changes in the status or operation of the logging process are also recorded. The data may be logged at regular intervals (specified in hundredths of seconds in the Log_Interval property), or upon a change of value (COV). The COV value comes from either the Trend_Log’s Client_COV_Increment property when using Trend COV, or the trended point’s COV_Increment property when using the Point COV option (Client_COV_Increment will be NULL). Each time-stamped buffer entry is called a trend log record. The Buffer_Size property specifies the maximum number of records the buffer can hold.

Figure 58. BACnet Trending Concept Drawing.



In an APOGEE BACnet field panel, the trended object (point) must reside in the same field panel as the Trend Log object.

Each Trend Log object maintains an internal buffer that fills, or grows, as log records are added. If the buffer becomes full, there are two options: the oldest record is overwritten when a new record is added, or collection may be set to stop (Stop_When_Full property set to TRUE). If logging stops when full, the Log_Enable property will be set to FALSE (off). The buffer may be cleared by writing a zero to the Record_Count property. Each record in the buffer has an implied SequenceNumber which is equal to the value that the Total_Record_Count property has immediately after the record is added. If the Total_Record_Count is incremented past 232 -1, then it shall reset to 1.

Logging may be enabled and disabled (Log_Enable property) and at dates and times specified (Start_Time and Stop_Time properties). Disabling the log overrides timed operation. Trend Log enabling and disabling is recorded in the log buffer.

Notification is available to initiate automatic uploading of log records from the field panel to the mass storage device (computer). BACnet supports two ways to accomplish this: algorithmic or intrinsic notification. APOGEE BACnet supports intrinsic reporting, which sends a new notification to the computer when the Records_Since_Notification, the number of records collected since the last notification (or startup), equals the Notification_Threshold property value. The sequence number of the record that triggered the notification is recorded in the Last_Notify_Record property. In response to a notification, the subscriber (computer) initiates an upload of the new records using a service called ReadRange. There is also a methodology for a subscriber to detect a missed notification by analyzing parameters of the previous and the current notification.

One of the properties of the Trend Log object is the identity (instance number) of a Notification Class object. This object contains a Recipient List property that identifies the devices (Insight workstations) that upload the trend data. Also identified are the days and time range in which that device will upload the trend data. The Notification Class object is in the same field panel as its related Trend Log object.

The acquisition of log records by remote devices has no effect upon the state of the Trend Log object itself. This allows completely independent, but properly sequential, access to its log records by all remote devices. Any remote device can independently update its records at any time.



Table 35 shows the properties of the Trend Log Object as documented in the ANSI/ASHRAE Standard 135-2004.

Table 35. Properties of the Trend Log Object Type.

Property Identifier Property Data Type Conformance Code

Object_Identifier BACnetObjectIdentifier R

Object_Name CharacterString R

Object_Type BACnetObjectType R

Description CharacterString O

Log_Enable BOOLEAN W

Start_Time BACnetDateTime O1,2

Stop_Time BACnetDateTime O1,2

Log_DeviceObjectProperty BACnetDeviceObjectPropertyReference O1

Log_Interval Unsigned O1,2

COV_Resubscription_Interval Unsigned O

Client_COV_Increment BACnetClientCOV O

Stop_When_Full BOOLEAN R

Buffer_Size Unsigned32 R

Log_Buffer List of BACnetLogRecord R

Record_Count Unsigned32 W

Total_Record_Count Unsigned32 R

Notification_Threshold Unsigned32 O3

Records_Since_Notification Unsigned32 O3

Last_Notify_Record Unsigned32 O3

Event_State BACnetEventState R

Notification_Class Unsigned O3

Event_Enable BACnetEventTransitionBits O3

Acked_Transitions BACnetEventTransitionBits O3

Notify_Type BACnetNotifyType O3

Event_Time_Stamps BACnetARRAY[3] of BACnetTimeStamp O3

Profile_Name CharacterString O 1 These properties are required to be present if the monitored property is a BACnet property. 2 If present, these properties are required to be writable. 3 These properties are required to be present if the object supports intrinsic reporting.

For more information about APOGEE trending and how to use trend data after it is captured, see the APOGEE Trending Application Guide (125-1899).




Although BACnet trending differs from non-BACnet APOGEE trending, the APOGEE user interfaces can make the two appear to be very similar. This section explains some of the differences and how to setup an APOGEE BACnet trend.

APOGEE Trending: Non-BACnet vs. BACnet

Table 36 shows some of the differences between APOGEE non-BACnet and BACnet trending.

Table 36. Comparison of APOGEE Trending–non-BACnet vs. BACnet.

APOGEE Non-BACnet APOGEE BACnet

Trend info is in the point record Trend info (including point info) is in Trend_Log object

Optional trend trigger No trend trigger

COV and/or interval trending (can have up to 1 COV and 4 interval per point)

COV and/or interval trending (can have up to 1 COV and 4 interval per point)

Circular file only (writes over oldest data when buffer is full)

Circular file or stop-when-full feature

Data cleared when trend is disabled Can be disabled without data loss

Scheduling Trends

Although the Trend_Log object has its own Start/Stop Date/Time, it can still be scheduled by the Scheduling application in the field panel. Using the Scheduling application offers more flexibility than just using the Trend_Log times. For example, Scheduling a trend allows programming different start and stop times for weekends, holidays, etc. The Trend_Log’s Start/Stop times are unchanging day after day.

Scheduling Trend Collections

Trend data can be collected (uploaded) to the storage device (computer) periodically based on a trend collection schedule. This can be in addition to the automatic notification and uploading that occurs through the Notification_Class and Notification_Threshold properties in the Trend Log object. When points are trended by the interval method, the trend buffer fill at a predictable rate, so the collection of trend data can be easily scheduled.

Schedule a BACnet trend log object using the conventional non-BACnet Insight scheduling. From either the Daily or Monthly tab, select a starting day for the trend collection on the Monthly calendar in the right hand corner of the Schedule window. Next, from the Schedule menu, select New, and then Trend Collection. When the object selector displays, select the BACnet trend log object. Click OK and complete the process by completing the fields in the Trend Collection Schedule dialog box.



The Trend Wizard automatically sets up a trend collection schedule. Trend data is collected every two hours throughout the day. Figure 59 shows a trend collection schedule established by the trend wizard.

Figure 59. Trend Collection Schedule automatically set up by Trend Wizard.

Notification Class

The Notification Class object contains a list of what devices (Insight workstations) are notified to upload a trend log buffer when it reaches its notification threshold. A Notification Class is created for a Siemens Building Technologies’ field panel through the System Profile application. Double-clicking on the desired field panel symbol opens the BACnet Field Panel Definition window. See Figure 60 and note the Notification Classes button.



Figure 60. BACnet Field Panel Definition Window.

The Notification Classes button displays the Notification Classes dialog box. New Notification Class Instances can be created by clicking Add, which displays the BACnet Notification Class dialog box (Figure 61).

The name and descriptor of the Notification Class object can be written so as to encode the name of the group of recipients of the trend data or the type of trend data that uses this Notification Class.

The Priority values relate to the BACnet events (transitions) that are generated by the Trend_Log object. For APOGEE BACnet field panels, only the To Normal Priority is used for trending. This transition occurs when a notification is triggered–the value of the Records_Since_Notification property becomes equal to or greater than the value of the Notification_Threshold property. This number can be high (192 through 255) for trend data of low importance and lower (128 through 191) for important trend data.

The Trend Log TO-FAULT transition is intended for failed COV subscription attempts, but since APOGEE requires the Trended point, Trend Log and Notification Class to be in the same panel, COV subscription is not used. The To Off-Normal Priority and the Ack field are in the Notification Class object for when it is used for alarming (Notify_Type property is Alarm) and can be ignored for trend notification.

As explained in Chapter 8–BACnet Alarming, the alarm priorities in a Notification Class object can each be assigned values from 0 to 255. This alarm priority is mapped to the following six APOGEE alarm levels:

0-31 is A1 (life safety)

32-63 is A2 (property safety)



64-95 is A3 (supervisory)

96-127 is A4 (trouble)

128-191 is A5 (high priority alarms)

192-255 is A6 (low priority alarms)

None of the Ack (acknowledge) check boxes need be selected.

Figure 61. BACnet Notification Class Dialog Box.

Recipient List

The Recipient List defines what device (Insight workstation) is notified to upload a trend log buffer when it reaches its notification threshold. Create a Recipient List for the selected Notification Class by clicking the lower Add button in the Notification Class dialog box to open the BACnet Destination dialog box (Figure 62).



Figure 62. Recipient Creation using the BACnet Destinations Dialog Box.

The BACnet Destination dialog box has the following sections:

Recipient–The easiest way to identify a recipient is by Device Instance number. To determine an Insight workstation’s Instance Number, Open the System Profile and double-click on the BLN serving the device originating the alarm. The Building Level Network Definition dialog box will display the Instance Number of the Insight workstation assigned to the BLN will appear (Figure 63).



Figure 63. Viewing an Insight’s Instance number from System Profile.

Recipient Process–This number is obtained from the manufacturer of the field panel originating the alarm. The APOGEE Automation System enters 600 by default.

Transitions–Check only the TO NORMAL box.

Valid Days and Period–To ensure unimpeded collection of trend data check all days and select the <any> wildcard entry for the dates.

Notifications–Confirmed Notifications should be chosen for high priority trend data.

Create additional Notification Classes and Recipient Lists as required using the Add button.


Chapter 10–BACnet Tools

Chapter 10 describes tools for analyzing BACnet communications in an APOGEE Building Automation System. It discusses the following topics:

BAS-o-matic Protocol Analyzer

Commissioning Tool Support for APOGEE BACnet Field Panels

Insight BACnet Communications Tools

BAS-o-matic Protocol Analyzer

Cimetrics™ BAS-o-matic is a tool for analyzing communication packets on a network–a type of Packet Sniffer. To debug communication problems, the user captures packets and then sends them to the manufacturer of the device that generated the packets so they can be analyzed. In the case of Siemens Building Technologies, the packets are sent to field support.

BAS-o-matic can be run on the Insight competitor on other computers (notebooks) when desired. This allows flexibility in where and when the tool is used. Using the Insight workstation is usually easier, and BAS-o-matic does not in any way interfere with Insight operations. BAS-o-matic will work on Ethernet, BACnet/Ethernet, BACnet/IP, BACnet MS/TP, and Modbus.

BAS-o-matic enables the network card's promiscuous mode and can capture network traffic on the local segment of the LAN. Thus, it normally captures and analyzes packets addressed to all of the computers on the segment, not only to the one where the program is running. There are certain limitations for Wireless Ethernet adapters (you can monitor only inbound/outbound traffic) and switched networks.

Obtaining BAS-o-matic

BAS-o-matic is a product of Cimetrics, Inc. A free version of the installation program (demo version - no license or dongle required) is included with Insight Revision 3.7. It is located on CD#3 as a zip file in a folder named BAS-o-matic. Alternatively, all versions—including the demo version—can also be downloaded from www.Cimetrics.com. From the Cimetrics’ home page, use the following path to download the installation program:

Connectivity Products >> Building Automation Products >> BACnet Installation Tools >> B5020 - BAS-o-matic v5.0 Protocol Analyzer–Details >> Download v5.0 DEMO (5.2Mzip).

The demonstration version has many features relative to capturing packets but, unlike the fully featured versions, does not provide for interpretation and analysis of the packets.



Connecting to a Network

When using a separate computer to run BAS-o-matic, a dumb hub or a switch that supports “port mirroring” is needed to interface the BAS-o-matic computer to the network. When using the Insight computer to run BAS-o-matic, no special network hookup is required.

A hub is needed to interface a separate BAS-o-matic computer to the network. This needs to be a truly dumb Ethernet hub–one that will show all packets at every port all the time. For example, the NETGEAR Model EN104 and model EN108. Switches (and certain hubs that act like switches) read the addresses of incoming data and allow only certain data to pass. Thus, the BAS-o-matic will only capture packets sent to and from the computer on which it is running.

BAS-o-matic will also work with switches that support port mirroring. This is a feature that allows redirecting the traffic of some or all ports to a designated monitoring port on the switch. Monitoring the entire LAN segment then becomes possible.

Most modern switches support port mirroring. A switch’s specifications and documentation will disclose if the switch has port mirroring. Be aware that various manufacturers name this feature differently. Table 37 is a short list of switches by three major manufacturers.

Table 37. Partial List of Switches that Support Port Mirroring.

Manufacturer Name Used for the Port Mirroring Feature

Models of Switches with Port Mirroring Support

Cisco Switched Port Analyzer (SPAN) Cisco Catalyst 1900 Series Switches

Cisco Catalyst 4500 Family Switches

Cisco Catalyst 6000 Family Switches

3COM Roving analysis port (RAP) 3Com SuperStack 3 Switch 4400

Intel Port mirroring Intel Express 460T

Intel Express 480T

Connecting a Separate BAS-o-matic Computer

To connect a separate BAS-o-matic computer to the network:

1. Acquire three regular Ethernet patch cables.

2. Disconnect the Insight workstation from the main network and plug it into the hub.

3. Plug the BAS-o-matic computer into the hub. Connect the hub’s uplink port to the main network using the jack that the Insight computer was connected to.

4. Make sure the network card in the BAS-o-matic computer is properly installed in the operating system.



Using the Insight Workstation for BAS-o-matic

No hub or special connection to the network is needed. The Insight workstation stays plugged into the network.


There are no special Commissioning Tool (CT) applications for BACnet, but all of the applications support BACnet. However, the level of support varies, as explained in the following sections.

Commissioning Tool support is limited to APOGEE BACnet devices only. Third-party BACnet devices are NOT supported.

For the Custom Solution BACnet MEC, Commissioning Tool allows import of point information on a Microsoft Excel spreadsheet into the Point Editor. However, importing spreadsheets is not available for use with third-party field panels.

The following sections explain the levels to which the Commissioning Tool applications support APOGEE BACnet field panels.

Firmware Loading Tool

The Firmware Loading Tool (FLT) application allows you to load new firmware into a field panel's flash memory and change configuration data. FLT also provides the capability to identify and flash BACnet field panels.

MMI Database Transfer

The MMI Database Transfer (MMIXfer) application supports BACnet field panels. This involves connecting to the panel’s MMI port, building the system profile, performing backup/restore operations for ALN/FLN devices (including APOGEE BACnet devices), and communicating in terminal mode.

Build System Profile

The MMI Database Transfer application includes a Build System Profile command for BACnet field panels.

Backup/Restore

MMI Transfer application provides capability to back up/restore APOGEE BACnet field panels to the Commissioning Tool (job) database. This includes support for the following BACnet-specific objects:

Calendar



Command

Notification Class

Schedule

Terminal Emulation

Terminal Emulation is available for operator interface with a field panel. A COM port or a modem can be used for communication between a computer and a field panel.

Copy Field Panel

The Copy Field Panel application is used to duplicate all (or selected parts) of an existing field panel’s data (except PPCL) into a newly created field panel. The application supports BACnet by being able to duplicate an APOGEE BACnet field panel’s data to create a new BACnet field panel. Data components that must be unique in each panel, such as Instance Number and System Name, are not copied.

The Copy Field Panel application also allows duplication of an APOGEE BACnet field panel to an APOGEE Ethernet, P2, and Remote Building Level Network (ALN). The copied field panel becomes an Ethernet field panel or P2 field panel, depending on the ALN to which it is copied.

Copy Field Panel also provides functionality to duplicate an Ethernet or P2 Field Panel to a BACnet ALN. The copied field panel becomes a BACnet field panel.

Point Transfer

The Point Transfer (XPoint) application allows points to be transferred from the Job database into a Microsoft® Excel spreadsheet or from an Excel spreadsheet into the Job database. In Excel, new points can be added or existing points can be modified, and then the changes can be imported to the Job database.

Point Transfer provides limited support for APOGEE BACnet field panels. Only APOGEE non-BACnet data is transferred to or from the Excel spreadsheet.

When transferring BACnet point data to Excel, you lose the BACnet-specific parts of the point data (Instance Number, Notification Class, Annunciate flags, etc.).

When transferring Excel point data to a BACnet panel in the Job database, default values are inserted where possible. For example, Instance Numbers are set to -1, and Notification Class is set to 0.

Therefore, it is necessary for the user to manually fill-in the missing BACnet-specific data.



Non-Field Panel Data Transfer

The Non-Field Panel Data Transfer (NFData) application (formerly known as CT/Insight Transfer) is used for importing or exporting non-field panel data (events, graphics, reports, etc.). The application functions by transferring the data between a job database and an XML file. The Non-Field Panel Data Transfer application is included with Insight Revision 3.7 (it must be installed separately for earlier revisions).

The Non-Field Panel Data Transfer application supports APOGEE BACnet field panels but not third-party devices.

Point Summary Report

The Point Summary Report application allows you to create a printed document that contains information about the points in field panels and devices. The information can also be exported to a Microsoft® Excel (or other) spreadsheet application. In Excel, the report can be modified, saved as an Excel worksheet, and printed.

Although the Point Summary Report application works with APOGEE BACnet field panels, reports will not contain any BACnet-specific information such as Notification Classes, Instance Numbers, etc.

Point Checkout Data

The Point Checkout Data application allows users to view a point report in Microsoft® Notepad as a comma-separated text file. The application supports APOGEE BACnet field panels, but the report does not display any BACnet-specific point data like Instance Number and Notification Class. The report displays the following information:

Point name

Point descriptor

Point type

Point address

Alarmable

Controller

Commissioning Report Generator

The Commissioning Report Generator (CRG) application is a tool that allows a user to create, print, and save report forms that can be used for submitting a proposed job database for review, as well as document the results of start-up and commissioning of field panels and FLN devices (for example, MBCs, TECs, Unitary Controllers).

The CRG supports the BACnet Field Panel Point Report; however, only APOGEE point-like objects appear in the report. For APOGEE BACnet field panels, the report displays the following:

Point Address



Present_Value

The IP address of the APOGEE BACnet panel is not displayed.


Several software tools are available in the Insight System Profile application Tools menu to assist in troubleshooting BACnet communications problems.

Multiple Device Configuration

The Multiple Device Configuration Tool enables the user to set some device properties across a list of selected devices. The Multiple Device Configuration Tool (Figure 64) is accessed by clicking BACnet Multiple Device Configuration from the Tools menu in the System Profile application.

Figure 64. Multiple Device Configuration Dialog Box.

Some notes about the operation of the Multiple Device Configuration tool are:

The list cannot be empty and will remove duplicates automatically.

The object selector will show cloaked devices so the user can uncloak them.



At least one checkbox must be selected.

The same limits are enforced as in the Advanced Settings dialog box (accessed through the BACnet Field Panel Definition dialog box).

A summary of errors (if any) appears after the operation completes.

Global Broadcast Who-Is

Clicking this menu item broadcasts a Who-Is message to all devices on the network. This tool is intended to be used with the discovery process. For information, see Device Discovery in Chapter 4–BACnet Communications.

Custom Send Who-Is Diagnostic Tool

The Who-Is Diagnostic Tool enables a user to send out a Who-Is message and view I-Am responses from devices on the network. The Who-Is message can be directed at a specific range of device numbers on a specific network or can be global (the default).

This tool can be used to locate devices that, for some reason, the device discovery process did not locate. If a response is gotten by this tool but the device is not on a BLN, then the BACnet Device Connection Settings (filtering) may be wrong or the device may be cloaked (see Glossary and Chapter 4–BACnet Communications).

The Who-Is Diagnostic Tool (Figure 65) is accessed by clicking BACnet Custom Send Who-Is from the Tools menu in the System Profile application.

Figure 65. Who-Is Diagnostic Tool Dialog Box.

I-Ams are added to the dialog box as they are received. The columns sort when the heading is clicked. A Total Count box lists the total number of I-Ams received.



Enable Device Discovery

Clicking the Enable Device Discovery menu item starts the discovery process for all devices on the network. See the Device Discovery section in Chapter 4–BACnet Communications.

BACnet Device Communication Control

BACnet Device Communication Control allows the user to control the communication of a BACnet device (field panel). The following device communication control is available to the user:

Enable–Allows the device to respond to commands

Disable–Stops a device from initiating or responding to commands. (The device will only respond to Device Communication Control and Reinitialization messages.)

Disable Initiation Only–Stops a device from initiating commands but allows it to respond to commands. (It will respond to a Who-Is with one I-Am.)

This feature is useful when running tests on other devices on the network and a certain device or devices may interfere with those tests. For example, if certain devices are communicating a lot, the network may be too noisy to test the communication of other devices. This tool allows the user to quiet the noisy devices for the time the tests have to be run.

The Insight Help message gives another example. A user can disable the communications of a field panel on which a power fail test is to be run so that alarms are not sent to Alarm Status.

When the testing is completed, the field panel communication can be manually enabled or communications will automatically enable after the Disable duration time has elapsed. Setting the time to 0 disables the timer and keeps the field panel disabled until it is manually enabled.

CAUTION:

Use caution when disabling (entering a value of 0) the Disable duration timer. Device communication will not be able to resume until manually enabled.

There is no global enable command. Devices to be enabled must be specifically selected–either individually or more than one. If the selected devices require passwords, they MUST be enabled individually.

Unauthorized disabling of communication is restricted because the field panel password (if the panel was so configured) must be entered for this function to operate. For third-party BACnet devices, contact the manufacturer for the device password. For Siemens Building Technologies’ field panels, use the high account password.

Some third-party BACnet devices may not support Device Communication Control. For more information, see the manufacturers user documentation and/or Protocol Implementation and Conformance Statement (PICS).

The BACnet Device Communication Control dialog box (Figure 66) is accessed from the Tools menu in the System Profile application.



Figure 66. BACnet Device Communication Control Dialog Box.

BACnet Communication Diagnostic

The BACnet Communication Diagnostic tool is used to configure the Insight BACnet communication wait time based on the analysis of APDU response times from field panels. An APDU (Application Protocol Data Unit) is a message that originates in an application program of one BACnet device and is sent to the application program of another BACnet device(s). For example, an APDU can be a point command and the response is the confirmation that the command was successful. When an APDU is sent, a response from the other BACnet device(s) is expected. The issue is how long to wait (timeout) for a response before trying again, and how many attempts or retries should be made before quitting.

This tool helps do the following:

Give a suggestion for the best time to use the APDU timeout. The Suggested APDU Timeout is calculated by adding four seconds to the largest Response Time for a test ADPU issued by the Insight application.

Help test for APDU turnaround time, and show how slow some devices are communicating on the BACnet network. This can be done by running multiple tests, each with a reduced BACnet APDU timeout value. When a panel does not respond (request timed out), the Current BACnet APDU Timeout value is less than the turnaround time. Adjusting the BACnet APDU Timeout allows zeroing in on the turnaround time.

Assist in response tuning. If a panel’s turnaround time is inconsistent, a decision can be made for the best compromise timeout value.

The BACnet Communication Diagnostic tool allows you to test a single device or select all BACnet panels in the database. Operation is as follows:

Press Begin. The device(s) are sent a request for the value of a read property.

The Responses Received columns fill in accordingly:



The number of seconds it takes for each device to respond is displayed in the Response Times [in Seconds] column. If it takes longer than the BACnet APDU timeout value entered at the top of the dialog box, The request timed out message displays.

The APDU times that Insight is using for each device is displayed in the Current APDU Timeout column. The initial default value is 5 seconds.

The APDU timeout recommended for each device is displayed in the Suggested APDU Timeout column.

After Test Complete appears, clicking Begin again does not clear the columns. Instead, another set of response times, separated by commas, are written in the columns.

If the Response Time and the Current APDU Timeout differ for a field panel, the suggested timeout can replace the current timeout by highlighting the field panel row and clicking the Set APDU Timeouts button. Multiple rows can be highlighted and set with one click of the set button, but if a row with errors is selected, it will be skipped and the APDU timeout will not be changed for that device.

APDU Timeout and Retries are BACstac settings to control how long a command has to complete before timing out and how many times to retry the command. The Insight software enforces a minimum of 1 retry and 5 second timeout. These values are set in the Advanced Settings of the BACnet Field Panel Definition. In the Insight software, this dialog box appears in System Profile.

CAUTION:

Some third-party devices may have default timeout values that are way too long. For example, anything over 30 seconds is too long and should not be required. If a panel’s turnaround time is slow and a long timeout is required, it will slow the operation of the Insight application. Long turnaround time issues for a panel must be resolved with the manufacturer.

The BACnet Communication Diagnostic dialog box (Figure 67) is accessed from the Tools menu in the System Profile application.



Figure 67. BACnet Communication Diagnostic Dialog Box.

CAUTION:

The timeouts in this tool are for Insight software only. A field panel has its own, single timeout value and retry value that it uses when it requests data from other devices. These two values are read only and can be accessed through the Object Browser by viewing the ADPU_Timeout and Number_of_ADPU_Retries properties of the Device Object of the field panel. The APOGEE BACnet field panel firmware sets these values to three seconds for timeouts and three retries


Glossary

This glossary describes various terms and acronyms used in this application guide. For a comprehensive listing of building control terminology, see the Technical Glossary of Building Controls Terminology and Acronyms (125-2185).

ASHRAE

American Society of Heating, Refrigerating and Air-Conditioning Engineers. An HVAC industry organization for advancing the arts and sciences of heating, refrigeration, air conditioning, and ventilation for the benefit of the general public.

ANSI

American National Standards Institute.

Application Protocol Data Unit (APDU)

A unit of data specified in an application protocol and consisting of application-protocol-control-information and possibly application-user-data (ISO 9545).

ARCNET

Attached Resource Computer Network. Type of LAN that works like a token-ring network, except that the connections between computers do not need to be in the shape of a ring. ARCNET networks usually use Ethernet hardware.

B-BC

See BACnet Building Controller Profile.

B-OWS

See BACnet Operator Workstation Profile.

BACnet

Data communication protocol for Building Automation and Control networks, ANSI/ASHRAE Standard 135-1995. BACnet allows devices from multiple manufacturers to work together.


Glossary

BACnet Building Controller Profile (B-BC)

BACnet defines a B-BC as a general-purpose, field-programmable device capable of carrying out a variety of building automation and control tasks.

BACnet Device ID

A number, between 0 and 222, assigned to a BACnet device by the person configuring a BACnet network. This number must be unique per job (internetwork). Also called Device Instance Number.

BACnet Foreign Device

A BACnet device (workstation or field panel) that has an IP connection but does not have a BBMD or multicast router on its subnet to allow it access to BACnet broadcast messages.

BACnet Interest Group (BIG)

Associations formed by BACnet users for the benefit of BACnet users. BIGs enable individuals to exchange information and share experiences about the implementation and application of BACnet. Many BACnet Interest Groups have formed around the world to support BACnet users. There is BIG-NA, North America (www.big-na.org); BIG-EU, Europe (www.big-eu.org), and BIG-AA, AustralAsia (www.big-aa.org).

BACnet Internetwork

Two or more BACnet networks interconnected by routers.

The job (the whole BACnet network on a job). This includes all BACnet segments regardless of media or protocol or networking technology (ARCNET, MS/TP, etc.).

BACnet Interoperability Building Block (BIBB)

Collections of one or more BACnet services that function to define the interoperational capabilities of a BACnet device. Certain BIBBs may also be predicated on the support of certain, otherwise optional, BACnet objects or properties. BIBBs may also constrain allowable values of specific properties or service parameters.

BACnet Router

A device that interconnects two or more BACnet networks to form a BACnet internetwork. BACnet routers make use of BACnet network layer protocol messages to maintain their routing tables. A router may, or may not, provide BACnet application layer functionality.


Glossary

BACnet/IP Broadcast Management Device (BBMD)

An application that forwards BACnet/IP broadcast messages across IP routers. One BBMD must appear on either side of an IP router, and communicate using unicast messages.

BACnet Operator Workstation Profile (B-OWS)

BACnet defines a B-OWS as ‘the operator’s window into a BACnet system. Primarily used for on-line operations.

BACnet Testing Laboratories™ (BTL)

Laboratories formed by the BACnet Manufacturers Association (currently known as BACnet International) to test building automation products and certify them as BACnet compliant.

BBMD

See BACnet/IP Broadcast Management Device.

BIBB

See BACnet Interoperability Building Block.

BTL

See BACnet Testing Laboratories™.

Building Level Network (BLN)

An RS-485 network for use by the APOGEE building level controllers.

Communication trunk connecting Insight computers and field panels in a building control system. You must have a BLN Account in order to access and perform operations at a field panel on a specific BLN.

change-of-value (COV)

Method of sampling (trending) point values at a field panel. A COV is recorded when the change in a point value is greater than the user-defined COV limit (analog points) or when there is a change of state for a digital point.

Cloaking

A process which removes BACnet devices from BLNs in System Profile and prevents the Insight device discovery process from re-adding the devices. In Insight, accessed through a check box in the BACnet Field Panel Definition dialog box.


Glossary

Datagram

A term used to describe data that is put into packets for network transport.

Device Instance Number

See BACnet Device ID.

Domain Name System (DNS) Domain Name Server (DNS)

An Internet service that translates domain names into IP addresses.

Alphabetical domain names (www.example.com) are easier to remember for humans, but the Internet is based on IP addresses. So a DNS server does the translation into the corresponding IP address. If one DNS server can’t translate a particular domain name, it asks another one in the DNS network, and so on, until the correct IP address is returned.

Default method of name resolution for Windows 2000. The domain naming service (DNS) allows computers on a domain to determine the Computer Name assigned to an IP address or the IP address assigned to a computer name. Windows 2000 uses Dynamic DNS where the name table for the domain is automatically updated as computers join the network or become unavailable.

Electronic Protocol Implementation Conformance Statement (EPICS)

A self-documentation file that lists all of the objects, properties and services supported by a device.

EPICS

See Electronic Protocol Implementation Conformance Statement.

Ethernet

Type of protocol developed by the IEEE (802.3) that maps to the Physical layer in local area networks.

A combination wiring and signaling standard for networking. The IEEE standard 802.3 that defines the functions of the Logical Link Control sub-layer of the Data Link layer in the OSI model. Also defined are the network operations of the Physical and Data Link layers. Ethernet is the most popular form of local area network.

A high-speed LAN which runs on a variety of media-STP, coaxial cable, or fiber optics.


http://webopedia.internet.com/TERM/D/Internet.html

http://webopedia.internet.com/TERM/D/domain_name.html

http://www.example.com/

Glossary

Floor Level Network (FLN)

Network consisting of Terminal Equipment Controller (TEC), Unitary Controllers (UC), fume hoods, etc.

An FLN allows application specific controllers to communicate with field panels. This allows for the controllers to be manipulated from central points in the field panels.

Foreign Device

See BACnet Foreign Device.

Group Object

The Group object type defines a standardized object whose properties represent a collection of other objects and one or more of their properties. A group object is used to simplify the exchange of information between BACnet Devices by providing a shorthand way to specify all members of the group at once. A group may be formed using any combination of object types

Half-Router

In BACnet, a device that can participate as one partner in a point-to-point (PTP) connection. Two half-routers form an active PTP connection and act as a single router.

Instance Number

In BACnet, a number that uniquely identifies an object within a device or a device on an internetwork. Device Objects are required to have an instance number that is unique internetwork-wide. Instance numbers may range from 0 to 4194303. For devices, see BACnet Device ID.

Integrated Systems Architecture (ISA)

A Siemens initiative to standardize BACnet usage across Siemens business units.

Internetwork

See BACnet Internetwork.

Interoperability Area (IA)

BACnet defines functionality in terms of "Interoperability areas" (IAs). The five IAs are data sharing, alarm and event management, scheduling, trending, and device and network management.


Glossary

Internet Protocol (IP)

Acronym for Internet Protocol. IP handles the breaking up of data messages into packets (also called datagrams), the routing of the packets from their origin to the destination network and node, and the reassembling of the packets into the data message at the destination. IP operates at the internetwork layer of the TCP/IP model, which is equivalent to the network layer of the ISO/OSI reference model.

IP Address

Address that is assigned to every computer and all Ethernet BLN and BACnet controllers. An IP address uniquely identifies a node on the network.

The 32-bit address used to identify a computer on a network using the IP protocol. A 4-octet number like 128.253.245.74. An IP address is separated into the network address portion and the host portion.

IPsec (IP security) (Internet Protocol security)

A standard for securing Internet Protocol communications by encrypting and/or authenticating all IP packets. IPsec provides security at the network layer.

Local Area Network (LAN)

Network of computers and other devices that is confined to an office, a building, or a company.

LonTalk

Echelon Corporation’s LAN technology. It is a specification for the Physical and Data Link layers of their protocol architecture.

Media Access Control (MAC)

The part of a network that handles access to the physical network (media). In BACnet, each device has a unique MAC Address/Network Number combination that identifies it on the BACnet internetwork.

MS/TP

MS/TP (Master-Slave/Token-Passing) is an Electronics Industry Alliance (EIA) standard for multipoint communications–contrary to just point-to-point communications like RS-232. MS/TP is also known as RS-485 or EIA-485.


http://en.wikipedia.org/wiki/Internet_Protocol

http://en.wikipedia.org/wiki/Encryption

http://en.wikipedia.org/wiki/Authentication

http://en.wikipedia.org/wiki/Network_layer

Glossary

National Institute of Standards and Technology (NIST)

An agency of the U.S. Department of Commerce's Technology Administration. The NIST charter is to strengthen the U.S. economy and improve the quality of life by working with industry to develop and apply technology, measurements, and standards. NIST has played an integral role in the development of BACnet.

Operates a lab where manufacturers can test their products for BACnet conformance.

"Native" BACnet

A phase that implies that whatever is being described only speaks and understands BACnet.

Network

Collection of Insight workstations, field panels, printers, and equipment controllers that are electronically and physically connected to communicate with each other for sharing building control data.

Object

In a BACnet system it is a piece of information described by its properties. An object might represent information about a physical input or output, or it may represent a logical grouping of points that perform some function, such as a setpoint. Every object has an identifier (such as AI-1) that allows the BACnet system to identify it. An object is similar to a data point, although it contains additional information other than present value. It is only through its properties that an object is monitored and controlled.

Point-to-Point (PTP)

Point-to-Point Protocol - a protocol provided by an Internet Service Provider (ISP) for connection to the Internet via a dial-up connection. PTP is faster, more reliable and supports more functions than the comparable SLIP protocol. PTP also applies to RS-232 (EIA-232) connections

Properties

The means by which objects are monitored and controlled. BACnet specifies 123 properties of objects. Three properties-Object-identifier, Object-name, and Object-type-must be present in every object. BACnet also requires that certain objects support specific additional properties. The type of object and the type of device in which that object resides determine which properties are present. Some properties can accept writes, and others can only be read.

Protocol for Data Communications

A set of rules governing the exchange of data over a computer network.


Glossary

Protocol Implementation Conformance Statement (PICS)

A document that details the particular BACnet objects, services and capabilities supported by a type of BACnet device. Every BACnet-compliant device has an associated PICS published by the manufacturer.

Available from building automation control vendors, a PICS documents such things as supported conformance class, functional groups, standard application services, standard object types, data link layer options, character sets, and any special functionality built into the protocol.

Router

Device used to connect networks using different architectures and protocols. Routers determine the best path for sending data, and filter broadcast traffic to the local segment.

A device that connects two LANs. Routers are similar to bridges, but provide additional functions, such as message filtering and forwarding based on various criteria. A router is a physical device that is used to pass messages on the network level (network layer of the OSI model).

Serial Line Internet Protocol (SLIP)

A protocol provided by an Internet Service Provider (ISP) for connection to the Internet via a dial-up connection. SLIP can be used on RS-232 serial ports and supports asynchronous links. SLIP is not as common as PPP.

Services

How one BACnet device gets information from another device, commands a device to perform certain actions (through its objects and properties, of course), or lets other devices know that something has happened. The only service that is required to be supported by all devices is the Read-property service. There are a total of 32 standard services.

Subnet

See Network.

Target Target Reference

In BACnet scheduling, the BACnet Object Property Reference. That which is written to by the BACnet schedule.

Third-party BACnet Device

A non-APOGEE /non-Siemens Building Technologies BACnet device. A BACnet device from another manufacturer. Not to be confused with a BACnet Foreign Device.


Glossary

Third-party BACnet Workstation

A non-Insight workstation that is on or reachable through BACnet/IP. The level of interoperability that may be achieved is limited by many factors.

TCP/IP

Transmission Control Protocol/Internet Protocol. TCP/IP is the de facto protocol standard used by the Internet. Whereas IP deals only with packet transmission, TCP enables two hosts to establish a connection and exchange streams of data. TCP handles delivery and order of data streams.

User Datagram Protocol (UPD)

Used for internetworking, UDP is a connectionless transport protocol that facilitates transport of the IP.

User Datagram Protocol is an alternative transport service to Transmission Control Protocol (TCP). Most internet messages are encapsulated in a TCP frame. TCP is a “reliable”, connection-oriented transport service. That is, it guarantees that the message reaches its destination. Since the BACnet protocol itself guarantees delivery, TCP is not required. Thus, BACnet can use UDP instead. UDP is a connectionless transport layer protocol that exchanges datagrams (packetised data) without acknowledgments or guaranteed delivery

Virtual network

The representation of P2 ALN devices and points as BACnet objects to the rest of the BACnet internetwork. This is achieved by the Insight BACnet Server. Virtual network is a BACstac term.

WAN (Wide Area Network)

A connection that ties together computers or LANs in locations across a city, country, or even overseas.


Glossary


Index

BACnet Interoperable Building Blocks, 37 A BACnet Networking Technologies, 45

BACNET Object Browser, 63 Alarm Acknowledgement, 103 BACnet Operator Workstation (B-OWS) Profile,

44 Alarm Acknowledgements, 105 Alarm Acks, 60

BACnet Protocol Model, 46 Alarm and Event Management, 40 BACnet Router vs. IP Router, 55 Alarm and Event Priority, 103 BACnet Schedule Object Operation, 82 Alarm Enable/Disable, 104 BACnet Scheduling Example 1, 90 Alarm Message Definition, 116 BACnet Scheduling Example 2, 92 Alarm Messages, 62, 107 BACnet Scheduling Example 3, 93 Alarm Priority, 62, 106 BACnet Scheduling Example 4, 93 Algorithmic Change Reporting, 98 BACnet Scheduling Example 5, 94 Analog Input Object, 16 BACnet Scheduling Examples, 90 Analog Output Object, 18 BACnet Scheduling Theory, 81 Analog Value Object, 19 BACnet Text Messages, 61, 106 APOGEE BACnet Field Panel, 57 BACnet Trending in APOGEE, 123 APOGEE GO, 62, 108 BACnet Trending Theory, 119 APOGEE Trending: Non-BACnet vs. BACnet,

123 BACnet/IP, 50 Basic BACnet Networking, 47 Attribute Duplicator, 63 BAS-o-matic Protocol Analyzer, 131

B Binary Input Object, 20 Binary Output Object, 21 Backup and Restore, 69 Binary Value Object, 23 Backup/Restore, 134 BLN Account TAB, 78 Backward Compatibility, 60 BLN Definition, 73 BACnet Address Table, 73 BTL Certification, 58 BACnet Alarming Example, 108 Build System Profile, 133 BACnet Alarming Theory, 97 Building Controller Profile (B-BC) and Operator

Workstation Profile (B-OWS), 42 BACnet Alarms, 60 BACnet and APOGEE, 104 BACnet and Insight Scheduling, 88 C BACnet Broadcast Management Device

(BBMD), 51 Calendar Object, 26, 87 Certification, 3, 34 BACnet Browser, 107 Change Of Value (COV) Reporting, 97 BACnet Browser Features, 64 Cloaking, 73 BACnet Browser Limitations, 65 Command Object, 27, 84 BACnet Building Controller (B-BC) Profile, 42 Command Priority, 76 BACnet Communication Diagnostic, 139 Command Priority Array Strings, 73 BACnet Communications, 50 Command Priority Array vs. APOGEE, 9 BACnet Device, 14 Command Priority Properties, 8 BACnet Device Communication Control, 138 Commissioning Report Generator, 135 BACnet Device Database Storage, 89 Commissioning Tool Support for APOGEE

BACnet Field Panels, 133 BACnet Device Profiles, 41 BACnet Export, 79

Connecting a Separate BAS-o-matic Computer, 132

BACnet Foreign Devices, 54 BACnet Implementation within APOGEE, 3


LTD Point, 110 Connecting to a Network, 132 Copy Field Panel, 134

M D

Master-Slave/Token-Passing, 45 MMI Database Transfer, 133 Data Sharing, 39 Modifying the Priority Array, 10 Database Transfer, 68 Multiple Device Configuration, 136 Device Communication Control, 75 Multi-State Input Object, 24 Device Management, 40 Multi-State Output Object, 24 Device Re-Initialization, 75 Multi-State Value Object, 25 Display BACnet Priority, 71

Dynamic Plotter, 70 N

E Native BACnet and B-OWS, 59 Native BACnet Devices On The Same LAN, 47 Enable Device Discovery, 138 Native BACnet Devices with Different LAN

Technologies, 48 Event Information and Alarm Summary, 61 Event Log, 70

Native BACnet to Non-Native BACnet Devices, 49

Event Printer, 70 Event Scheduling, 89

Network Management, 40 F Non-Field Panel Data Transfer, 135

Notification Class, 99, 115, 124 Field Panel Features, 57 Notification Class Object, 27 Field Panel Hardware, 57

File Object, 27 O Firmware Loading Tool, 133

Object Types, 69 FLN Devices, 74 Objects Theory, 5 Floating Alarm Limits, 105 Obtaining BAS-o-matic, 131

G One-Hop, 51 Operation, 12 Get Event Information vs. Alarm Summary, 105 Organization of Guide, I Getting Help, III Other Changes, 70 Global Broadcast Who-Is, 137 Other Objects Supported by APOGEE BACnet

Field Panels, 26 H

How BACnet was Developed, 3 P I Panel Configuration Report, 71

Panel Display Report, 72 Impact to MMI, 13 Panel Point Definition Report, 71 Impact to PPCL, 13 Panel Trend Definition Report, 72 Impact to TEC Subpoints, 14 Point Checkout Data, 135 Initials, 60, 105 Point Commander, 65 Insight Account Tab, 78 Point Definition Report, 71 Insight BACnet Communications Tools, 136 Point Objects, 107 Insight BACnet Option, 59 Point Priority, 60 Insight Changes for BACnet, 60 Point Summary Report, 135 Interoperability, 33 Point Transfer, 134 Intrinsic Reporting, 98 Point-Like Objects, 16

L Program Editor, 70 Progress Tab, 68 L2SL Point, 109 Properties of Objects, 6 Life Safety Alarms, 106 Protocol Implementation and Conformance

Statement, 35 Log Tab, 68 LonTalk Cautions, 46

Purpose of this Guide, I



PXC Compact Slope/Intercept, 70

R

Recipient List, 126 Recipient List (Destinations), 100 Reference Materials, II RENO Notification, 70, 108 Report Builder/Reports, 71 Reports, 71

S

SAT Point, 111 Schedule Object, 27, 82 Schedule Object Properties that Can be

Commanded, 89 Scheduler, 73 Scheduling, 39 Scheduling Trend Collections, 123 Scheduling Trends, 123 Send Comments, III Services Not Supported, 32 Services Supported, 31 Services Theory, 29 Specifying BACnet, 34 SSP Point, 114 Start Stop Time Optimization (SSTO), 89 Symbols, II System Messages, 105 System Profile, 73 System Profile Report, 72

T

Terminal Emulation, 134 The OBJECT_TYPE Property, 7 Time-of-Day Scheduling, 76 Totalization Log Report, 72 Transitions and Event States, 101 Trend Data Detail Report, 72 Trend Definition Report, 72 Trend Definitions, 76 Trend Editor, 76 Trend Log Object, 27 Trending, 40 Two-Hop, 52

U

Unknown BACnet alarms, 61 Unknown BACnet Alarms, 106 Upload Selected Dialog, 69 User Account Report, 72 User Accounts, 76 Using the Insight Workstation for BAS-o-matic,

133

V

Viewing with the BACnet Browser, 28

W

What is BACnet?, 1 Who-Is Diagnostic Tool, 75

Custom Send, 137 Why BACnet was Developed, 2

www.buildingtechnologies.siemens.com

125-1984T

Siemens Industry Inc.Building Technologies Division1000 Deerfield ParkwayBuffalo Grove, IL. 60089USA1-847-215-1000

Copyright © 2012 Siemens Industry, Inc.Printed in the USA

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