Series 200 Centrifugal Chiller BACnet Variables...0A0B 1 = R12 2 = R22 3 = R134a 4 = R114 5 = R500...

Open Protocol Data Information Packet Version 2.2

Group: Controls

Date: March 1999

© 2002 McQuay International

MicroTech®Series 200 Centrifugal Chiller

Data Communications Packet for Open Protocol™

Series 200 Centrifugal Chiller 2

Revision HistoryVersion 2.2 3/99 Changed the Communications Signal $047D. A value of 255 must be written

to this location every minute to establish communications with open protocol!

Added High Suction Superheat (value 45 for current fault)

Changed definition of the communications status $040C point

Version 2.1 1/98 Added read only point communications status $040C, to monitorcommunication status. This is used in conjunction with communicationssignal $047D.

Added verbiage. The control mode setpoint (read/write $0477) must bewritten to both the master and slave units when 2 Series 200 centrifugalchillers are in the lead/lag configuration.

Version 2.0 Removed I/O hardware list. This information is kept up to date in the productInstallation & Maintenance manual.

Added Communication Error (value 44 for current fault)

Added option for network enable (read/write) for chiller operation mode(value=1)

Version 1.1 4/96 This revision is a formatting change.

I/O configuration list added.

Memory locations for lead/lag operation added.

Version 1.0 6/95 Initial release of the document.

ProprietaryThis Document may not be copied or reproduced in any way without the express written consent ofMcQuay International.

NoticeCopyright © 1999McQuay International, Minneapolis MN

All rights reserved throughout the world.

McQuay International reserves the right to change any information contained herein without priornotice. No guarantees are given as to the accuracy of information provided.

3 Series 200 Centrifugal Chiller

Contents

Revision History ................................................................................................................................... 2Contents ................................................................................................................................................ 3Overview.................................................................................................................................4Introduction........................................................................................................................................... 4Network Configuration ......................................................................................................................... 4Compatible Unit Control Software ....................................................................................................... 4Supplemental Literature ........................................................................................................................ 5Conversions and Conventions............................................................................................................... 5Glossary of Terms................................................................................................................................. 6Read Only Memory Location Tables .................................................................................................... 6Read Only Memory Definitions.......................................................................................................... 10Read and Write Memory Location Table............................................................................................ 18Read and Write Memory Definitions .................................................................................................. 19Lead/Lag Load Balance Operation ....................................................................................21Overview............................................................................................................................................. 21Read/Write Memory Locations........................................................................................................... 21Read Only Memory Locations ............................................................................................................ 22Series 200 Centrifugal Chiller Simulator Package ...........................................................23Purpose................................................................................................................................................ 23Development Tools ............................................................................................................................. 23Monitor Installation............................................................................................................................. 23Hardware Configuration ..................................................................................................................... 23Testing................................................................................................................................................. 24Simulator Monitor Software Guide ....................................................................................24Logging on to the software ................................................................................................................. 24Communications Initialization ............................................................................................................ 25Downloading Simulation code............................................................................................................ 26Monitoring a simulator controller ....................................................................................................... 28Read/Write screens ............................................................................................................................. 28Further Information on Windows Monitor Software .......................................................................... 29


Overview

IntroductionMcQuay International’s Open Protocol™ for MicroTech® Series-200 centrifugal chillers allowsindependent building automation system companies to integrate McQuay® centrifugal chillerequipment into their building control systems. Automation integrators can communicate with asingle chiller or a networked group of chillers with simple RS-485 communications. Using OpenProtocol, the integrator has access to relevant control information and may alter the equipmentoperating state by adjusting specific controller memory locations provided by McQuay.

This manual completely defines accessible memory locations and provides instructions on the use ofMcQuay’s Open Protocol Hardware Development Kit. With the manual and development kit, a fullyfunctional interface to McQuay Series-200 centrifugal chillers can easily be developed.

The purpose of a chiller is to cool the water that passes through it. When the unit is operating, theMicroTech controller monitors the leaving chilled water temperature and compares it to the chilledwater temperature setpoint. If the water temperature is not the desired value, the controller willadjust unit operation to achieve the setpoint temperature.

McQuay manufactures two types of centrifugal chillers: single compressor and dual compressorunits. Single compressor units have one MicroTech control panel and dual units have two. In a dualconfiguration, each panel controls one of the two compressor circuits in the unit. Sequencing controland load balancing logic for dual units can be provided by either control panel. The panel whichcontrols these functions is selected by the unit operator.

Network ConfigurationThe Network interface on the OPM is a daisy chained, multi-drop, 9600 baud, RS-485 proprietaryMcQuay network interface.

The chiller controller is factory mounted and provides pre-programmed, pre-engineered and pre-tested stand-alone control. There is one controller for each chiller. A dual chiller is considered tobe 2 chillers and thus has two controllers.

When the McQuay network has been commissioned (by a McQuay representative), the BAS vendorcan connect to the McQuay interface controller. Chillers continue to operate even whencommunications are lost; the network must be intact for the BAS to control the chillers.

Compatible Unit Control SoftwareYou must know IDENT of the software in the chiller to know which variables are applicable. Thesoftware IDENT includes the version number (the last two numbers) of the software and its revisionlevel (the last letter). Your McQuay representative can give you this information, or if the unit isalready installed, the IDENT information may be read directly from the keypad display.

Note: Software revisions do not affect variables; however, software versions typically indicate amajor change in the software. Usually, software changes do not affect variables either.

This edition of this Open Protocol information packet documents revision I of the standard softwareand all subsequent revisions of version 04 until otherwise indicated. If you encounter a later versionof code, please refer to McQuay Online for an update to this document.


This Open Protocol document specifically addresses chiller applications utilizing MicroTechSeries-200 control software. McQuay has provided a means of verifying the use of Series-200software by embedding an eight character software identification string in the unit controller’s readonly memory. The string is written as ASCII characters in a hex number format and is located inmemory locations 0A08-0A0F. The table below defines valid identification strings.

Address Characters Description

0A08, 0A09,0A0A

C, F, G Defines code as Series-200 chiller. (Always the 1stthree characters.)

0A0B 1 = R122 = R223 = R134a4 = R1145 = R500

Refrigerant type.

0A0C E = EnglishS = SI/MetricD = Kana(Japanese)

Display - Units of measure / language type.

0A0D, 0A0E 01-99 Software version number.

0A0F A-Z Software revision number.

The software version number typically indicates a significant change in the control code. Thisdocument is valid for all version of software code up to the latest version which is version 4. Therevision character may change frequently and indicates minor changes to the control code and nevereffects open protocol. An upgrade in version number generally does not effect open protocol either.Please connect to McQuay Online if a later version of code is encountered in the field to see if theinformation contained in this document is still valid.

Supplemental LiteratureUse the following manuals with this information packet. Operation manuals contain a detailedsequence of operation. Installation and Maintenance manuals contain unit wiring details. OM-125 Series 200 MicroTech Control Panel Operation ManualIM 615 Series 200 MicroTech Control Panel Installation Manual

Conversions and Conventions

Note on TemperaturesAll temperatures are stated in degrees Fahrenheit, to get degrees Celsius, you must use the standardformula for temperature conversion:

C F=

× −5 329

( )

Note on PressuresAll pressures are stated in PSI, to get KPA, you must use the following standard conversion:

KPA PSI= ×689.


Glossary of TermsBAS Building Automation System

KPA Kilopascals

OAT Outdoor Air Temperature

PSI Pounds Per Square Inch

RLA Rated Load Amps

Read Only Memory Location Tables

Description Address Range (X) Conversion Units

Chilled WaterTemperature- ActiveSetpoint

0905 0-160 X/2 °F

Chiller Unit TemperatureType0 = Standard1 = Low Temperature

084B 0, 1

Communication Status0 = Communications time-out1 = Active communications

040C 0,1

Compressor Lift Pressure 046A-046B 0-65,535 X/10 PSIG

Compressor Motor Current 044C-044D 0-65,535 Amps

Compressor Motor CurrentPercent

044A 0-125 %

Compressor Number ofStarts

085F-0860 0-49,999 Compressorstarts

Compressor OperatingHours

0851-0852 0-49,999 hrs

Compressor SuctionTemperature

043A-043B 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Compressor Superheat -Discharge

046E-046F 0-2,630 X / 10 ºF

Compressor Superheat -Suction

046C-046D 0-2,630 X / 10 ºF

Condenser ApproachTemperature

0484-0485 0-2,630 X / 10 °F

Condenser Heat RecoveryUnit Present0 = Not Present1 = Present

083F 0, 1

Condenser Heat RecoveryTemperature - Delta

048A-048B 0-2,630 X / 10 °F



Condenser Heat RecoveryWater Temp. - Entering

0454-0455 600-3,63063,985 =Short61,425 =Open58,865 =N/A

(X - 1000) /10

°F

Condenser Heat RecoveryWater Temp. - Leaving

0456-0457 600-3,63063,985 =Short61,425 =Open58,865 =N/A

(X - 1000) /10

°F

Condenser Pump Status 0425 0-7 See Below

Condenser Pump # 1Operating Hours

085A-085B 0-49,999 hrs

Condenser Pump # 2Operating Hours

085D-085E 0-49,999 hrs

Condenser RefrigerantPressure

0440-0441 0-4,50063,985 =Short61,425 =Open

X / 10 PSIG

Condenser RefrigerantTemperature

0466-0467 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Condenser SubcoolingTemperature

0480-0481 0-2,630 X / 10 ºF

Condenser Water FlowRate

0452-0453 0-65,535 GPM

Condenser Water FlowStatus

045F 0, 1 0 = No Flow1 = Flow

Condenser Water RateSensor0 = Not Present1 = Present

083D 0, 1

Condenser WaterTemperature - Delta

0488-0489 0-2,630 X / 10 °F

Condenser WaterTemperature - Entering

0436-0437 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Condenser WaterTemperature - Leaving

0434-0435 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F



Cooling Tower Control0 = External1 = Chiller

0926 0, 1

Cooling Tower Stage 049A 0-6 stages

Cooling Tower ValvePosition

049B 0-100 %

Discharge RefrigerantTemperature

043E-043F 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Evaporator ApproachTemperature

0482-0483 0-2,630 X / 10 °F

Evaporator Pump Status 0423 0-7 See Below

Evaporator Pump #1Operating Hours

0854-0855 0-49,999 hrs

Evaporator Pump #2Operating Hours

0857-0858 0-49,999 hrs

Evaporator RefrigerantPressure

0438-0439 0-1,50063,985 =Short61,425 =Open

X / 10 PSIG

Evaporator RefrigerantTemperature

0464-65 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Evaporator Water FlowRate

0450-0451 0-65,535 GPM

Evaporator Water FlowStatus0 = No Flow1 = Flow

045E 0, 1

Evaporator Water RateSensor0 = Not Present1 = Present

083C 0, 1

Evaporator WaterTemperature - Delta

0486-0487 0-2,630 X / 10 °F

Evaporator WaterTemperature - Entering

0432-0433 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Evaporator WaterTemperature - Leaving

0430-0431 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F



Fault - Current Active 1C00 0-43 See Below

Last Start Hour 0861 0-23 hour

Last Start Minute 0862 0-59 minute

Last Start Month 0863 1-12 month

Last Start Date 0864 1-31 day

Last Start Year 0865 0-99 year

Last Stop Hour 0866 0-23 hour

Last Stop Minute 0867 0-59 minute

Last Stop Month 0868 1-12 month

Last Stop Date 0869 1-31 day

Last Stop Year 086A 0-99 year

Liquid Line RefrigerantTemperature

043C-043D 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Oil Pressure - Feed 0446-0447 0-4,50063,985 =Short61,425 =Open

X / 10 PSIG

Oil Pressure - Net 0468-0469 0-4,500 X / 10 PSIG

Oil Pressure - Vent 04AC-04AD

0-1,50063,985 =Short61,425 =Open

X / 10 PSIG

Oil Temperature - Feed 0442-0443 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Oil Temperature - Sump 0444-0445 600-3,63063,985 =Short61,425 =Open

(X - 1000) /10

°F

Outdoor Air Temperature -Network

0474 60-252253=N/A255= BadSen

X-100 °F

Refrigerant DetectionSensor0 = Not Present1 = Present

083E 0, 1

Refrigerant Leak DetectionLimit

044B 0-100 PPM

Unit Status 0420 0-27 See Below


Read Only Memory DefinitionsA definition name followed by an asterisk (*) indicates that the data point is not always supported.

Chilled Water Temperature - Active Setpoint 0905The chilled water temperature location contains the active chilled water setpoint the unit is using fortemperature control. The active setpoint may be set by several control scenarios which aredependent upon chiller configuration parameters. A data range of 0 to 160 corresponds to thetemperature range of 0ºF to 80ºF with 0.5ºF resolution.

Chiller Unit Temperature Type 084BUnit temperature type indicates whether the unit is a low or standard discharge temperature unit. Avalue of zero indicates a standard chiller unit; a one indicates a low temperature unit.

Communication Status 040CThis point monitors the status of network communications. If the read/write point communicationssignal expires, the value in the location will become zero. A one will be read if the communicationssignal is active.

Compressor Lift Pressure 046A-6BLift pressure is the pressure rise of the refrigerant gas as it passes through the compressor. Liftpressure is calculated by subtracting evaporator refrigerant pressure from the condenser refrigerantpressure. It is a two byte value, where location 046A contains the high byte and 046B contains thelow byte. The BAS integrator should assume this value will always be valid. The resolution of thevalue is 0.1 PSIG.

Compressor Motor Current 044C - 4DMotor current holds the number of electrical Amps. being drawn by the compressor motor measuredwith a 1.0 A resolution. The data is a two byte value, where location 044C contains the high byteand 044D contains the low byte. The range for this data is dependent on the size of the motor. TheBAS integrator should assume this value will always be valid.

Compressor Motor Current Percent 044AMotor current percent stores the number of electrical Amps. the compressor motor is drawing as apercentage of its Rated Load Amps (RLA). The data represents a valid percentage only if theresultant value is between 0-125% of RLA. The resolution of the value is 1.0%.

Compressor Number of Starts 085F-60Number of starts stores the number of compressor motor starts that have occurred. Compressor startsis a two byte value, where location 085F contains the high byte and 0860 contains the low byte.These locations contain valid data only if the value is between 0 and 49,999. The value will roll overto 0 once the 50,000 start has occurred.

Compressor Operating Hours 0851-52Operating hours stores the number of hours the compressor has run. Operating hours is a two bytevalue, where location 0851 contains the high byte and 0852 contains the low byte. The data is validwhen in the range of 0 and 49,999. The value will roll over to zero (0) once the 49,999 hour hasbeen completed.

Compressor Suction Temperature 043A-3BSuction temperature is the temperature of the refrigerant gas entering the compressor. Suctiontemperature is a two byte value, where location 043A contains the high byte and 043B contains thelow byte. The data represents a valid temperature only if the resultant value is between -40°F and263°F. The resolution of the value is 0.1°F.


Compressor Superheat - Discharge 046E-6FDischarge superheat is the temperature difference between the refrigerant gas leaving the compressorand the refrigerant phase change temperature point. It is derived by subtracting a calculatedcondenser refrigerant phase change temperature from discharge refrigerant temperature. Superheattemperature is a two byte value, where location 046E contains the high byte and 046F contains thelow byte. The data represents a valid temperature only if the resultant value is between 0°F and263°F. The resolution of the value is 0.1°F.

Compressor Superheat - Suction 046C-6DSuction superheat is the temperature difference between the refrigerant gas entering the compressorand the refrigerant phase change temperature point. It is derived by subtracting a calculatedevaporator refrigerant phase change temperature from the compressor suction temperature. Superheattemperature is a two byte value, where location 046C contains the high byte and 046D contains thelow byte. The data represents a valid temperature only if the resultant value is between 0°F and263°F. The resolution of the value is 0.1°F.

Condenser Approach Temperature 0484-85The approach temperature is the difference in temperature between the condenser refrigerant and thecondenser leaving water. It is calculated by subtracting leaving condenser water temperature fromcondenser refrigerant temperature. The temperature is a two byte value, where location 0484contains the high byte and 0485 contains the low byte. The data represents a valid temperature onlyif the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F.

Condenser Heat Recovery Unit Present 083FThe heat recovery present location indicates whether the chiller has a condenser heat recovery unit.A zero indicates a heat recovery unit is not present; a one indicates a unit is present. Heat recoverytemperature data points are valid only if a heat recovery unit is present.

Condenser Heat Recovery Temperature - Delta* 048A-8BThe heat recovery present location indicates whether the chiller has a condenser heat recovery unit.A zero indicates a heat recovery unit is not present; a one indicates a unit is present. Heat recoverytemperature data points are valid only if a heat recovery unit is present.

Condenser Heat Recovery Water Temperature - Entering* 0454-55The entering recovery temperature is the temperature of the water flowing into the condenser heatrecovery unit. It is a two byte value, where location 0454 contains the high byte and 0455 containsthe low byte. The data represents a valid temperature only if a heat recovery unit is present and theresultant value is between -40°F and 263°F. The resolution of the value is 0.1°F.

Condenser Heat Recovery Water Temperature - Leaving* 0456-57The leaving recovery temperature is the temperature of the water flowing out of the condenser heatrecovery unit. It is a two byte value, where location 0456 contains the high byte and 0457 containsthe low byte value. The data represents a valid temperature only if a heat recovery unit is presentand the resultant temperature is between -40°F and 263°F. The resolution of the value is 0.1°F.

Condenser Pump Status 0425Pump status stores the operating status of the condenser water pumps.


Status Value

Condenser Pumps Off 0

Starting Condenser Pump #1 1

Starting Condenser Pump #2 2

Condenser Pump #1 On 3

Condenser Pump #2 On 4

Condenser Pump #1 Fail; Starting #2 5

Condenser Pump #2 Fail; Starting #1 6

Condenser Pumps #1 & 2 Failed 7

Condenser Pump #1 Operating Hours 085A-5BPump #1 operating hours stores the number of hours condenser pump #1 has run. Operating hours isa two byte value, where location 085A contains the high byte and 085B contains the low byte. Theselocations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the49,999 hour has been completed.

Condenser Pump #2 Operating Hours 085D-5EPump #2 operating hours stores the number of hours condenser pump #2 has run. Operating hours isa two byte value, where location 085D contains the high byte and 085E contains the low byte. Theselocations contain valid data when in the range of 0 and 49,999. The value will roll over to 0 once the49,999 hour has been completed.

Condenser Refrigerant Pressure 0440-41Refrigerant pressure is the pressure of the refrigerant gas in the condenser shell. The pressure is atwo byte value, where location 0440 contains the high byte and 0441 contains the low byte. The datarepresents a valid pressure only if the resultant value is between 0 and 450 PSIG. The resolution ofthe value is 0.1 PSIG.

Condenser Refrigerant Temperature 0466-67Refrigerant temperature is the temperature of refrigerant gas in the condenser shell. The temperatureis a two byte value, where location 0466 contains the high byte and 0467 contains the low byte. Thedata represents a valid temperature only if the resultant value is between -40°F and 263°F. Theresolution of the value is 0.1°F.

Condenser Subcooling Temperature 0480-81Subcooling is the temperature difference between the liquid refrigerant leaving the condenser and therefrigerant phase change temperature point. It is derived by subtracting the liquid line refrigeranttemperature from a calculated condenser refrigerant phase change temperature. The data represents avalid temperature only if the resultant value is between 0°F and 263°F. The resolution of the value is0.1°F.

Condenser Water Flow Rate* 0452-53Water flow rate stores the rate of water flowing through the condenser tubes. Water flow is a twobyte value, where location 0452 contains the high byte and 0453 contains the low byte. Theresolution for this value is 1 GPM and the range is dependent on the condenser flow sensor. If acondenser flow rate sensor is present the data will always be valid.

Condenser Water Flow Status 045FThe value in the condenser water flow status location indicates the position of the condenser waterflow switch. A zero indicates no water flow through the condenser; a one indicates water movement.

Condenser Water Rate Sensor 083DThe value in the condenser water rate sensor location indicates whether a condenser flow rate sensoris connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor is present.Condenser water flow rate data is valid only when this sensor is present.


Condenser Water Temperature - Delta 0488-89The delta temperature is the difference between the entering and leaving condenser watertemperatures. The value is calculated by subtracting entering condenser water temperature fromleaving condenser water temperature. The temperature is a two byte value, where location 0488contains the high byte and 0489 contains the low byte. The data represents a valid temperature onlyif the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F.

Condenser Water Temperature - Entering 0436-37Entering water temperature is the temperature of the water entering the condenser. It is a two bytevalue, where location 0436 contains the high byte and 0437 contains the low byte value. The datarepresents a valid temperature only if the resultant value is between -40°F and 263°F. The resolutionof the value is 0.1°F.

Condenser Water Temperature - Leaving 0434-35Leaving water temperature is the temperature of the water leaving the condenser. The watertemperature is measured with a 0.1°F resolution. It is a two byte value, where location 0434 containsthe high byte and 0435 contains the low byte. The data is valid only if the resultant temperature isbetween -40°F and 263°F.

Cooling Tower Control 0926The value in the cooling tower control location indicates whether cooling tower functions are beingcontrolled by the chiller unit or an external control system. A zero indicates that an external systemis being used; a one indicates that the chiller is providing control. Cooling tower data points are onlyvalid when the chiller is in control.

Cooling Tower Stage* 049AThe value in the cooling tower stage location indicates the number of cooling tower stages that areenergized. The data is valid only if tower control is provided by the chiller. The valid range is 0 to6.

Cooling Tower Valve Position* 049BThe valve position location stores the position of the cooling tower valve. The position is measuredas a percent of full open and has a 1% resolution. The data is valid only if tower control is providedby the chiller. The valid range is 0-100%.

Discharge Refrigerant Temperature 043E-3FDischarge refrigerant temperature is the temperature of the compressor refrigerant gas as it leaves thecompressor. The refrigerant temperature is a two byte value, where location 043E contains the highbyte and 043F contains the low byte. The data represents a valid temperature only if the resultantvalue is between -40°F and 263°F. The resolution of the value is 0.1°F.

Evaporator Approach Temperature 0482-83The approach temperature is the difference in temperature between the evaporator refrigerant and theevaporator leaving water. It is calculated by subtracting evaporator refrigerant temperature fromleaving evaporator water temperature. The temperature is a two byte value, where location 0482contains the high byte and 0483 contains the low byte value. The data represents a valid temperatureonly if the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F.

Evaporator Pump Status 0423Pump status stores the operating status of the evaporator water pumps.

Status Value

Evaporator Pumps Off 0

Starting Evaporator Pump #1 1

Starting Evaporator Pump #2 2

Evaporator Pump #1 On 3

Evaporator Pump #2 On 4


Status Value

Evaporator Pump #1 Fail; Starting #2 5

Evaporator Pump #2 Fail; Starting #1 6

Evaporator Pumps #1 & 2 Failed 7

Evaporator Pump #1 Operating Hours 0854-55Pump #1 operating hours stores the number of hours evaporator pump #1 has run. Operating hoursis a two byte value, where location 0854 contains the high byte and 0855 contains the low byte.These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0once the 49,999 hour has been completed.

Evaporator Pump #2 Operating Hours 0857-58Pump #2 operating hours stores the number of hours evaporator pump #2 has run. Operating hoursis a two byte value, where location 0857 contains the high byte and 0858 contains the low byte.These locations contain valid data when in the range of 0 and 49,999. The value will roll over to 0once the 49,999 hour has been completed.

Evaporator Refrigerant Pressure 0438-39Refrigerant pressure is the pressure of the refrigerant gas in the evaporator shell. The pressure is atwo byte value, where location 0438 contains the high byte and 0439 contains the low byte value.The data represents a valid pressure only if the resultant value is between 0 and 150 PSIG. Theresolution of the value is 0.1 PSIG.

Evaporator Refrigerant Temperature 0464-65Refrigerant temperature is the temperature of refrigerant gas in the evaporator shell. The temperatureis a two byte value, where location 0464 contains the high byte and 0465 contains the low byte. Thedata represents a valid temperature only if the resultant value is between -40°F and 263°F. Theresolution of the value is 0.1°F.

Evaporator Water Flow Rate* 0450-51Water flow rate stores the rate of water flowing through the evaporator tubes. Water flow is a twobyte value, where location 0450 contains the high byte and 0451 contains the low byte. Theresolution for this value is 1 GPM and the range is dependent on the evaporator flow sensor. If anevaporator flow rate sensor is present the data will always be valid.

Evaporator Water Flow Status 045EThe value in the evaporator water flow status location indicates the position of the evaporator waterflow switch. A zero indicates no water flow through the evaporator; a one indicates watermovement.

Evaporator Water Rate Sensor 083DThe value in the evaporator water rate sensor location indicates whether an evaporator flow ratesensor is connected to the unit. A zero indicates a sensor is not present; a one indicates a sensor ispresent. Evaporator water flow rate is only valid when this sensor is present.

Evaporator Water Temperature - Delta 0486-87Water temperature delta is the difference between the entering and leaving evaporator watertemperatures. The value is calculated by subtracting evaporator leaving water temperature fromentering evaporator water temperature. The temperature is a two byte value, where location 0486contains the high byte and 0487 contains the low byte. The data represents a valid temperature onlyif the resultant value is between 0°F and 263°F. The resolution of the value is 0.1°F.

Evaporator Water Temperature - Entering 0432-33Entering water temperature is the temperature of the water entering the evaporator. It is a two bytevalue, where location 0432 contains the high byte and 0433 contains the low byte. The datarepresents a valid temperature only if the resultant value is between -40°F and 263°F. The resolutionof the value is 0.1°F.


Evaporator Water Temperature - Leaving 0430-31Leaving water temperature is the temperature of the water leaving the evaporator. The watertemperature is measured with a 0.1°F resolution. It is a two byte value, where location 0430 containsthe high byte and 0431 contains the low byte. These locations contain valid data only if the resultanttemperature is between -40°F and 263°F.

Fault - Current Active 1C00The fault location holds the current unit fault. If multiple faults should occur, the most serious faultwill be stored in this location.

Fault Condition Value

No Fault 0

Liquid Line Sensor Failure 1

Entering Evaporator Water Sensor Failure: Warning 2

Leaving Condenser Water Sensor Failure 3

Low Discharge Superheat 4

High Discharge Superheat 5

Entering Evaporator Water Sensor Failure: Problem 6

Outside Air Temperature Sensor 7

Low Evaporator Pressure - No Load 8

Low Evaporator Pressure - Unload 9

High Discharge Temperature Load 10

Condenser Freeze Protection 11

Evaporator Freeze Protection 12

Evaporator Pump #1 Failure 13

Evaporator Pump #2 Failure 14

Condenser Pump #1 Failure 15

Condenser Pump #2 Failure 16

Compressor Vanes Open at Startup 17

Low Evaporator Pressure 18

Low Oil Pressure Delta 19

Low Oil Feed Temperature 20

High Oil Feed Temperature 21

Low Compressor Motor Current 22

High Discharge Temperature 23

High Condenser Pressure 24

Mechanical High Condenser Pressure 25

High Compressor Motor Temperature 26

Surge-High Suction Superheat 27

Compressor Motor 28

No Evaporator Water Flow 29

No Condenser Water Flow 30

High Compressor Motor Current 31

Compressor Motor Starter Fault 32


Fault Condition Value

Leaving Evaporator Water Sensor Failure 33

Evaporator Pressure Sensor Failure 34

Entering Condenser Water Sensor Failure 35

Suction Temperature Sensor Failure 36

Discharge Temperature Sensor Failure 37

Condenser Pressure Sensor Failure 38

Oil Feed Pressure Sensor Failure 39

Oil Feed Temperature Sensor Failure 40

Oil Sump Temperature Sensor Failure 41

Oil Sump Pressure Sensor Failure 42

Voltage Ratio Sensor Failure 43

Communications Error 44

High Suction Superheat 45

Last Start Hour 0861The start hour location stores the hour value corresponding to the last time the unit started in militarytime.

Last Start Minute 0862The start minute location stores the minute value corresponding to the last time the unit started.

Last Start Month 0863The start month location stores the month value corresponding to the last time the unit started. Thevalue 1 corresponds to the month of January.

Last Start Date 0864The start date location stores the date value corresponding to the last time the unit started. The value1 corresponds to the first day of the month.

Last Start Year 0865The start year location stores the last two digits of the year corresponding to the last time the unitstarted.

Last Stop Hour 0866The stop hour location stores the hour value corresponding to the last time the unit stopped inmilitary time.

Last Stop Minute 0867The stop minute location stores the minute value corresponding to the last time the unit stopped.

Last Stop Month 0868The stop month location stores the month value corresponding to the last time the unit stopped. Thevalue “1” corresponds to the month of January.

Last Stop Date 0869The stop date location stores the day value corresponding to the last time the unit stopped. Thevalue “1” corresponds to the first day of the month.

Last Stop Year 086AThe stop year location stores the last two digits of the year corresponding to the last time the unitstopped.


Liquid Line Refrigerant Temperature 043C-3DLiquid line refrigerant temperature is the temperature of liquid refrigerant leaving the condenser.The refrigerant temperature is a two byte value, where location 043C contains the high byte and043D contains the low byte. The data represents a valid temperature only if the resultant value isbetween -40°F and 263°F. The resolution of the value is 0.1°F.

Oil Pressure - Feed 0446 - 47Feed pressure is the pressure at which refrigerant oil is being injected into the compressor. Oilpressure is a two byte value, where location 0446 contains the high byte and 0447 contains the lowbyte. The data represents a valid pressure only if the resultant value is between 0 and 450 PSIG.The resolution of the value is 0.1 PSIG.

Oil Pressure - Net 0468-69Net pressure is the difference between vent oil pressure and feed oil pressure. Oil pressure is a twobyte value, where location 0468 contains the high byte and 0469 contains the low byte. Theselocations contain valid data only if the resultant temperature is between 0 and 450 psi. Theresolution of the value is 0.1 PSIG.

Oil Pressure - Vent 04AC-ADVent pressure is the pressure of refrigerant oil in the oil vent return line. The pressure is a two bytevalue, where location 04AC contains the high byte and 04AD contains the low byte. The datarepresents a valid pressure only if the resultant value is between 0 and 150 PSIG. The resolution ofthe value is 0.1 psi.

Oil Temperature - Feed 0442 - 43Feed temperature is the temperature of the refrigerant oil being injected into the compressor. The oiltemperature is a two byte value, where location 0442 contains the high byte and 0443 contains thelow byte. These locations contain valid data only if the resultant temperature is between -40°F and263°F. It is measured with a 0.1°F resolution.

Oil Temperature - Sump 0444 - 0445Sump temperature is the temperature of the refrigerant oil that is collecting in the oil sump. The oiltemperature is a two byte value, where location 0444 contains the high byte and 0445 contains thelow byte. These locations contain valid data only if the resultant temperature is between -40°F and263°F. It is measured with a 0.1°F resolution.

Outdoor Air Temperature Method 083BThe OaT method location indicates the method by which the chiller is receiving the outdoor airtemperature value. A zero represents “None” and indicates no OaT value is used. A one represents“Local” and indicates that the temperature is supplied by a sensor connected to the chiller. A tworepresents “Network” and indicates that the temperature is being provided by the BAS network.

Outdoor Air Temperature - Network* 0474The network outdoor air temperature is an 8-bit converted value of the chiller outdoor airtemperature. It may be used by the BAS network for control situations that require a single byteoutdoor air temperature. The data in this location is valid only if OaT method is set to “Local.” Thevalid range of this value is -40°F to 152°F with a 1.0°F resolution.

Refrigerant Leak Detection Limit* 044BThe value in the refrigerant leak detection location is the parts per million (PPM) value of refrigerantparticles detected by the refrigerant leak detection sensor. If a sensor is present, the valid data rangeis 0 to 100 which corresponds to 0 to 100 PPM.

Refrigerant Detection Sensor 083EThe value in refrigerant detection sensor location indicates whether the unit has a refrigerant leakdetection sensor connected to the unit. A zero indicates a sensor is not present; a one indicates asensor is present. Refrigerant leak detection limit is only valid when a sensor is present.

Unit Status0420Unit status is the current unit status of the chiller. The following is a list of possible states and theircorresponding number.


State Name ValueOff: All Systems 0Off: Alarm 1Off: Ambient Temperature Lockout 2Off: Panel Rocker Switch 3Off: Manual 4Off: Remote Switch 5Off: Remote Communications 6Off: Time Schedule 7Start Requested 8Waiting for Low Oil SumpTemperature

9

Evaporator Pump Off 10Evaporator Pump On - Recirculation 11Evaporator Pump On - Cycle Timer 12Evaporator Pump On - Waiting forLoad

13

Oil Pump Off 14Oil Pump On - Pre-lubrication 15Condenser Pump Off 16Condenser Pump On - Waiting forFlow

17

Compressor Motor - Start UpUnloading

18

Compressor Motor - Started 19Compressor Motor - Running OK 20Compressor Motor - Rapid Shutdown 21Compressor Motor - Shut DownUnloading

22

Compressor Motor - Off Normal ShutDown

23

Condenser Pump - Off /Shut Down 24Evaporator Pump - Off/Shut Down 25Compressor Post Lubrication 26Oil Pump - Off/Shut Down 27

Read and Write Memory Location Table.


Capacity Limit Percent 0475 0-100 %Clear Current Fault0 = No Action1 = Clear Fault

041E 0-1


Description Address Range (X) Conversion UnitsChiller Operation Mode0 = Stop1 = Network Enable2 = Recirculate3 = Run

0477 0, 1, 2, 3

Chilled Water TemperatureSetpoint

0476 0-160 X/2 °F

Communications Signal0 = No Comm.255 = Enable Comm.

047D 0,255

Outdoor Air Temperature -BAS

0473 60-252253= N/A255= BadSen.

X - 100 °F

Read and Write Memory DefinitionsAll 0400 memory locations are stored in volatile memory and must be reset to desired value after apower loss.Capacity Limit Percent 0475The capacity limit percent location is used to define the upper limit for unit cooling capacity. Thenormal value for this location is 100%, which enables maximum cooling. The unit’s ability to coolmay be reduced by setting the limit to less than maximum. The limit value is a percentage of fullcapacity. The valid range for this location is 0-100%.

Clear Current Fault 041EThe clear current fault location is used to clear the current active fault and re-initialize the unitcontroller. Writing a one to this location initiates this action. Once the fault has been cleared thecontroller will set this location back to zero. Never write to this memory location withoutinvestigating and correcting the cause of the fault

Chiller Operation Mode 0477The value in the chiller operation mode location is set to indicate the desired chiller operating mode.There are three possible values. Zero indicates "Stop"; the compressor and water pumps will turn offand all valves will close. A one indicates that the chiller is enabled for operation, it will start basedupon sensed load. If there is no load the chiller will not start up. A two indicates "Recirculate"; thepumps will start and the valves will open to allow water to circulate through the system. However,the compressor will not start. A three indicates "Run"; the compressor and pumps will start and thevalves will modulate as required. When in the lead/lag configuration, the control mode must bewritten to both the master and the slave units.

Chilled Water Temperature Setpoint 0476The chilled water temperature setpoint holds the temperature the leaving evaporator water will becooled to if the unit is using this value for control. The data range of 0 to 160 corresponds to thetemperature range of 0ºF to 80ºF with 0.5ºF resolution. The setpoint should not be set below 40ºFfor standard temperature chiller units and may be set to 0°F for low temperature units.

See: Chilled Water Temperature - Active Setpoint and Chiller Unit Temperature Type on page 10.

Communications Signal 047DThe communications signal location is used to indicate active network communications between theBAS network and the chiller unit. A value of 255 should be written to this location once every 60seconds. If this location has not updated for five minutes, the chiller will assume there has been aloss of network communications and revert to internal setpoints for unit control.


Outdoor Air Temperature - BAS 0473The BAS outdoor air temperature location holds the value of the outdoor air temperature provided bythe BAS network. The BAS network should write an 8-bit outdoor air temperature to this location.The valid range for this value is 60-252, which corresponds to -40ºF to 152ºF.

See: Outdoor Air Temperature Method on page 17.


Lead/Lag Load Balance Operation

OverviewThe Master unit will select which unit should be the Lead unit (1) when both units are running, (2)when both units are off and (3) at the time and day selected, if any. Selection of the Lead unit takeseffect the next time a start is requested and both chillers are off.

Read/Write Memory Locations

Point NameAddres

s

Range Description

Master/Slave Setpoint 093C 0 = Master1 = Slave (default)

This memory address identifies aunit as either the Master or theSlave, for lead/lag purposes.1The Master controls the lead/lagprocessing.

Lead/Lag ModeSetpoint

093D 0 = Master is alwaysLead1 = Slave is alwaysLead2 = Auto-select(default)

This memory address controlsthe selection of the Lead unit.

Enable Lag Setpoint 093E 0 - 100% (default = 95) If the Lead unit is running aloneand its motor current exceeds thispercentage of its RLA, theinterstage timer will begin to run.When it expires, the Lag unitwill turn on (unless the Lag unithas been designated as standby).

Disable Lag Setpoint 093F 0 - 100% (default = 40) If both the Lead and Lag unitsare running and the motorcurrent of either drops below thispercentage of its RLA, theinterstage timer will begin to run.When it expires, the Lag unitwill shut off.

Lag Standby Setpoint 0942 0 = No (default)1 = Yes

This memory address determineswhether the Lag unit is to beused as a standby only.

Lead/Lag SwitchSetpoint (Day)

0948 0 = N/A (default)1 - 7 = Sunday -Saturday

This memory address containsthe day on which the Mastershould auto-select the Lead unit.

Lead/Lag SwitchSetpoint (Hour)

0949 0 - 23 (default = 0) This memory address containsthe hour at which the Mastershould auto-select the Lead unit.

1 Don't confuse the lead/lag terms "master" and "slave" with the configuration of communication ports as

master ports or slave ports.


Read Only Memory Locations

Point Name Address Range Description

Lead/Lag Status 0401 0 = Lead and Lag areoff1 = Lead in on2 = Lag is on3 = Lead and Lag are on

This memory address indicates whichunits are on.

Lead Unit 0402 0 = Master1 = Slave

This memory address indicates whichunit is the Lead unit.

Lead Unit Status 0403 Same as Unit Status(0420)

Unit status of the Lead unit.

Lag Unit Status 0404 Same as Unit Status(0420)

Unit status of the Lag unit.

Lead MotorCurrent

0405 0 - 100% Current drawn by Lead unit as apercentage of its RLA

Lag MotorCurrent

0406 0 - 100% Current drawn by Lag unit as apercentage of its RLA

Lead Status 0407 0 = Lead is disabled1 = Lead is enabled

Enabled/disabled status of the Leadunit.

Lag Status 0408 0 = Lag is disabled1 = Lag is enabled

Enabled/disabled status of the Lagunit.


Series 200 Centrifugal Chiller Simulator Package

PurposeMcQuay International offers hardware and software that will assist in the development of an openprotocol interface. These tools will allow the designer to set up a simulated unit, read informationfrom one communications port using McQuay Windows Monitor Simulation Software, and compareinformation from the BAS open protocol interface from a second communications port. If the BASinterface is working properly, the information read from the Windows Simulation Software will beidentical to the information read by the BAS interface.

Development ToolsMcQuay International offers the following tools to facilitate the development and testing of an OpenProtocol interface for Series 200 centrifugal chillers.

Literature:

• McQuay "Open Protocol Data Communications - Data Packet Protocol" document (version 1.0dated February or latest update).

Hardware required:

McQuay offers the following hardware for development:• Model 250 controller(s)

• Model 120• RS-232 Communications Cable package• RS-485 Communication Cable package

McQuay Open Protocol Monitor and Simulator software for Series 200 Centrifugal Chiller..

Monitor InstallationThe Microsoft® Windows™ environment is required to run the McQuay Open Protocol SimulatorMonitor software. Monitor software is currently available for download on McQuay On-line. Thesoftware is packaged in a self-extracting file which when executed, will install the software on yoursystem.

Hardware ConfigurationThe desired hardware configuration for proving out an Open Protocol interface is shown below. Inthis arrangement, the Open Protocol interface to the BAS (Building Automation System)communications device is operational on the controller's Port A, and the McQuay Monitor programis running on a PC connected to the controller's Port B.


For detailed wiring connections please consult McQuay Certified Drawing 573875Y.

TestingConfirm that each data point that has been set up within the BAS interface is properly interpreted anddisplayed. This is done by comparing the BAS system values with the values displayed by theMcQuay Monitor software.

When checking a variable (by using the Support - Read/Write menu option or by clicking on thevariable and using the "Change Value" dialog box), it is useful to test its high and low limits as wellas values within its normal working range. For example, if a temperature is valid between -40.0 °Fand 180°F, change the variable to -40°F and then 180°F. The chiller simulator control code and theMonitor program allow both read only and read/write variables to be modified to facilitate this kindof testing.Simulator Monitor Software Guide

Logging on to the softwareIf you have an old copy of the monitor software that has not been updated yet and a password isrequired and you can not get into the software, please contact McQuay International Controls andNetwork Systems Marketing group on McQuay On-line.

Simulator Monitor software released after January 1, 1997 will have a username: MCQUAYpassword: PARTNER.


Communications InitializationAfter logging in you will be asked to initiate communications

If you are connecting to a simulator controller you will want to select YES. If you are successful atconnecting you will be at the main screen. If you are unsuccessful you will see the following:

If you see this screen you may have a communications setup problem. You may select the ChangeSetup function to change communications parameters. You will come to a screen that looks like:


The problem is most likely you are using the wrong comm port on your PC. Check to make sure youare using either Comm 1 or Comm 2. The password for the controller will most likely be the defaultshown (FFFFFFFF). If for some reason your simulator has a different password, you may enter anew password here to try and establish communications to the controller. Note that this passworddoes not change the controller password, it merely tries to match one of the four level passwords thatexist in the controller. The connection type needs to be DIRECT, however the BAUD RATE doesnot need to match the baud rate that the controller port is set up for. When direct connecting to acontroller the monitor software will test all possible connection speeds from 300 to 9600 baud until aconnection is made or all baud rates have been attempted. Once you have adjusted the aboveparameters, you may attempt to connect to the controller once again by pressing the Init Commbutton.

Downloading Simulation codeOnce you have connected to the controller you may need to download simulator application code.From the Main Menu bar select the Support option. Under the menu items for support you will findDownload. Select Download and you should see the following screen:


The controller address should be 00.ff in the case of a single unit connection. 00.ff is a specialaddress which tells the software to connect to the direct connected controller regardless of thecontroller’s address setting. Alternately, you may enter the address of the controller, however whentrying to connect in this manner, the address must match. The Save Data, Download Program,Restore Data option should be chosen for every download. The program file will be the simulatorcode you wish to download to the controller. The data file is a temporary file in which controller datawill be stored during the download process. This file may be deleted off of your hard drive aftersuccessful download. You must specify a data file name but the name of the file is arbitrary. Thesave options you should have checked are Port Configuration and Passwords.

You should see the download progress dialog box after initiating the download:


Monitoring a simulator controllerOnce the code is properly downloaded into the simulator controller, you may begin to monitormemory locations in the Windows Simulator Monitor Software. From the Main Menu, chooseScreen, and select Monitor Unit. Double-click the appropriate screen to start seeing simulator data.

Read/Write screensYou may want to use the read/write screen (from support menu) in conjunction with the monitorscreens to double check the raw data values coming back from the controller. The following screen isan example of how to use the read/write screen for comparison. The Monitor Screen option has beenselected and the read/write option has also been selected (from the main menu, support option).


The above memory location for Chilled Water Temperature displays 44 degrees F. In the read/writescreen you can see the decimal value of memory location $0905 which is 88. The conversion in thiscase is value/2 to get degrees F.

Further Information on Windows Monitor SoftwareThis document should get you started using Windows Monitor. You should not have to use any ofthe other functions of Windows Monitor in order to test your interface. If further information onWindows Monitor is required, please refer to McQuay International MicroTech Monitor 1.0 forWindows User’s Manual.

13600 Industrial Park Boulevard, P.O. Box 1551, Minneapolis, MN 55440 USA (763) 553-5330 (www.mcquay.com)

Series 200 Centrifugal Chiller BACnet Variables...0A0B 1 = R12 2 = R22 3 = R134a 4 = R114 5 = R500...

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Transcript of Series 200 Centrifugal Chiller BACnet Variables...0A0B 1 = R12 2 = R22 3 = R134a 4 = R114 5 = R500...