Plc & scada Training Report

A

SUMMER TRAINING REPORT

ON

“PLC & SCADA Automation”

Submitted in the partial fulfilment for bachelor of technology degree at

Rajasthan Technical University, Kota

(2016-17)

Submitted To: - Submitted By: - Electrical Department

LakshminarayanVIET, Jodhpur B.Tech 4 th Year (7th Sem.)

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Department of Electrical Engineering

VYAS INSTITUTE OF ENGINEERING AND TECHNOLOGY, JODHPUR (Raj.)

Vyas Institute of Engineering and Technology,

Jodhpur (Rajasthan)

Department of Electrical Engineering

This is to certify that the student Lakshminarayan of final year, have successfully completed the seminar report titled “PLC & SCADA Automation” towards the partial fulfilment of the degree of Bachelor of Technology (B. TECH) in the Electrical Engineering of the Rajasthan Technical University during academic year 2016-17.

Guided by Head of the Department

Mr. Rahul Narang Prof. Manish Bhati

1 | P a g e V I E T , J o d h p u r

Certificate

ACKNOWLEDGEMENT

Theoretical knowledge every student of Engineering College takes training according to his own branch in a well-established factory or an organization in which work is being done practical and how practical work is managed in normal condition.

I am grateful to Mr Manish Bhati , the Head of Electrical Department VIET, Jodhpur for giving me the permission for training.

The divine support given by our guide Mr Rahul Narang , department of Electrical Engineering, VIET, Jodhpur , without whom work is not possible.

I am also helpful to Nitesh Saraswat in charge of AARMON TECH, Jodhpur and their sub ordinates and workers, which helped me a lot and shown the interest, it gives me a great pleasure in presenting my training report on “PLC & SCADA Automation”.

Trainee

Lakshminarayan [B.Tech. 4 t h Year]


CONTENT

ABSTRACT

Industrial training is must for every student perusing professional degree because the ultimate goal of every student is to get the information the industrial training helps us to get an idea of the things.

We should know in order to get a job i.e. I have a good professional career. Industrial training teaches us lots of thing s. it helps us to know the kind of environment we would be getting in the industry and help us to get with the kind of environment. The totality the industrial teaches us industrial ethics. Some advance technical how and help us to acquire with industrial working style.

Supervisory control and data acquisition (SCADA) allows a utility operator to monitor and control processes that are distributed among various remote sites. SCADA, is a system for gathering real time data, controlling processes, and monitoring equipment from remote locations. As more companies are implementing an open SCADA architecture through the Internet to monitor critical infrastructure components such as power plants, oil and gas pipelines, chemical refineries, flood control dams, and waste and water systems, vital systems are becoming increasingly open to attack. This report provides an overview of SCADA, outlines several vulnerabilities of SCADA systems, presents data on known and possible threats, and provides particular remediation strategies for protecting these systems.

PLCs are used in many different industries and machines such as packaging and semiconductor machines. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A programmable logic controller (PLC) or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or lighting fixtures. PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact.


ACKNOWLEDGEMENTS........................................................................................2

ABSTRACT.........................................................................................................3

TABLE OF CONTENTS..........................................................................................4

FIGURE INDEX ...................................................................................................5

1 AUTOMATION ............................................................................................7

1.1 TYPES OF AUTOMATION .............................................................................7

1.2 HISTORY....................................................................................................10

1.3 SIGNIFICANT APPLICATIONS.........................................................................11

1.4 ADVANTAGES AND DISADVANTAGES.............................................................12

1.5 HEALTH AND ENVIRONMENT........................................................................13

1.6 CONVERTIBILITY AND TURNAROUND TIME.....................................................13

1.7 AUTOMATION TOOLS...................................................................................14

2 SUPERVISORY CONTROL AND DATA ACQUISITION.........................15

2.1 WHAT IS MEANT BY SCADA? ...............................................................15

2.2 HISTORY OF SCADA..................................................................................15

2.3 SCADA SYSTEM SOFTWARE......................................................................18

2.4 SCADA KEY FEATURES.............................................................................18

2.5 APPLICATION OF SCADA...........................................................................23

3 PROGRAMMABLE LOGIC CONTROLLER (PLC).............................................25

3.1 WHAT IS MEANT BY PROGRAMMABLE LOGIC CONTROLLER..?.......................25

3.2 HISTORY OF PLC’S....................................................................................25

3.3 WHAT IS INSIDE A PLC..?...........................................................................26

3.4 INPUT / OUTPUT MODULE............................................................................26

3.5 OPERATION OF PLC...................................................................................27

3.6 PLC SCAN CYCLE .....................................................................................27

3.7 COMMUNICATION..................................................................................28

3.8 PROGRAMMING LANGUAGES USED TO PROGRAM A PLC..............................28

4 MICROLOGIX 1000 PLC SYSTEM................................................................29

4.1 INTRODUCTION OF MICROLOGIX 1000 PLC.................................................29

4.2 PLC COMPONENTS....................................................................................29

4.3 CONFIGURATIONS.......................................................................................30

4.4 CONNECTIONS OR WIRING..........................................................................30

4.5 INPUTS AND OUTPUTS................................................................................31

4.6 POWER SUPPLY.........................................................................................31


Figure index

4.7 I/O INTERFACES.........................................................................................31

4.8 ADDRESSING OF PLCS...............................................................................31

4.9 TYPES OF LANGUAGES...............................................................................32

4.10 ADVANTAGES.............................................................................................34

5 LADDER PROGRAMMING.............................................................................35

5.1 INTRODUCTION...........................................................................................35

5.2 INSTRUCTIONS...........................................................................................35

5.3 LOGIC GATES IN LADDER PROGRAMMING....................................................37

5.3.1 OR GATE.................................................................................................37

5.3.2 AND GATE...............................................................................................37

6 CONCLUSION.............................................................................................39

7 BIBLIOGRAPHY...........................................................................................40


1.1 AUTOMATION..............................................................................................13

2.1 FIRST GENERATION OF SCADA..................................................................15

2.2 SECOND GENERATION OF SCADA..............................................................15

2.3 THIRD GENERATION OF SCADA.................................................................16

2.4 SCADA SYSTEM .......................................................................................17

2.5 SCADA PROJECT .....................................................................................18

2.6 SCADA ALARM ........................................................................................18

2.7 SCADA TRENDS .......................................................................................19

2.8 SCADA DATABASE ...................................................................................20

2.9 SCADA PROJECT: SEWAGE WATER TREATMENT........................................23

3.1 PLC .........................................................................................................24

3.2 PLC SCAN.................................................................................................26

3.3 PLC HARDWARE........................................................................................27

4.1 PLC PROCESS ..........................................................................................28

4.2 PLC BLOCK ..............................................................................................29

4.3 PLC WIRING .............................................................................................29

4.4 PLC INPUT / OUTPUT..................................................................................30

4.5 LADDER LANGUAGE ...................................................................................31

4.6 BOOLEAN LANGUAGE..................................................................................32

4.7 GRAFCET LANGUAGE..................................................................................32

4.8 ALLEN- BRADLEY PLC................................................................................33

5.1 TON..........................................................................................................34

5.2 TOF..........................................................................................................35

5.3 RTO..........................................................................................................35

5.4 CTU..........................................................................................................35

5.5 CTD..........................................................................................................35

5.6 OR GATE.................................................................................................36

5.7 AND GATE...............................................................................................37

5.8 SCADA SOFTWARE ..................................................................................37

Chapter-1


Automation

Automation or automatic control is the use of various control systems for operating equipment such as machinery, processes in factories, boilers and heat treating ovens, switching in telephone networks, steering and stabilization of ships, aircraft and other applications with minimal or reduced human intervention. Some processes have been completely automated.

The biggest benefit of automation is that it saves labours; however, it is also used to save energy and materials and to improve quality, accuracy and precision.

The term automation , inspired by the earlier word automatic (coming from automaton), was not widely used before 1947, when General Motors established the automation department. It was during this time that industry was rapidly adopting feedback controllers, which were introduced in the 1930s.

Automation has been achieved by various means including mechanical, hydraulic, pneumatic, electrical, electronic and computers, usually in combination. Complicated systems, such as modern factories, airplanes and ships typically use all these combined techniques.

1.1 Types of automation

Two common types of automation are feedback control, which is usually continuous and involves taking measurements using a sensor and making calculated adjustments to keep the measured variable within a set range, and sequence control, in which a programmed sequence of discrete operations is performed, often based on system logic. Cruise control is an example of the former while an elevator or an automated teller machine (ATM) is an example of the latter.

The theoretical basis of feedback control is control theory, which also covers servomechanisms, which are often part of an automated system. Feedback control is called "closed loop" while non-feedback control is called "open loop."

1.1.1 Feedback control

Feedback control is accomplished with a controller. To function properly, a controller must provide correction in a manner that maintains stability. Maintaining stability is a principal objective of control theory.

As an example of feedback control, consider a steam coil air heater in which a temperature sensor measures the temperature of the heated air, which is the measured variable. This signal is constantly "fed back" to the controller, which compares it to the desired setting (set point). The controller calculates the difference (error), then calculates a correction and sends the correction signal to adjust the air pressure to a


diaphragm that moves a positioner on the steam valve, opening or closing it by the calculated amount. All the elements constituting the measurement and control of a single variable are called a control loop .

The complexities of this are that the quantities involved are all of different physical types; the temperature sensor signal may be electrical or pressure from an enclosed fluid, the controller may employ pneumatic, hydraulic, mechanical or electronic techniques to sense the error and send a signal to adjust the air pressure that moves the valve.

The first controllers used analog methods to perform their calculations. Analog methods were also used in solving differential equations of control theory. The electronic analog computer was developed to solve control type problems and electronic analog controllers were also developed. Analog computers were displaced by digital computers when they became widely available.

Common applications of feedback control are control of temperature, pressure, flow, and speed.

1.1.2 Sequential control and logical sequence control

Sequential control may be either to a fixed sequence or to a logical one that will perform different actions depending on various system states. An example of an adjustable but otherwise fixed sequence is a timer on a lawn sprinkler. An elevator is an example that uses logic based on the system states to perform certain actions in response to operator input.

A development of sequential control was relay logic, by which electrical relays engage electrical contacts which either start or interrupt power to a device. Relays were first used in telegraph networks before being developed for controlling other devices, such as when starting and stopping industrial-sized electric motors or opening and closing solenoid valves. Using relays for control purposes allowed event-driven control, where actions could be triggered out of sequence, in response to external events. These were more flexible in their response than the rigid single-sequence cam timers. More complicated examples involved maintaining safe sequences for devices such as swing bridge controls, where a lock bolt needed to be disengaged before the bridge could be moved, and the lock bolt could not be released until the safety gates had already been closed.

The total number of relays, cam timers and drum sequencers can number into the hundreds or even thousands in some factories. Early programming techniques and languages were needed to make such systems manageable, one of the first being ladder logic, where diagrams of the interconnected relays resembled the rungs of a ladder. Special computers called programmable logic controllers were later designed to replace these collections of hardware with a single, more easily re-programmed unit.

In a typical hard wired motor start and stop circuit (called a control circuit) a motor is started by pushing a "Start" or "Run" button that activates a pair of electrical relays. The "lock-in" relay locks in contacts that keep the control circuit energized when the push button is released. (The start button is a normally open contact and the stop button


is normally closed contact.) Another relay energizes a switch that powers the device that throws the motor starter switch (three sets of contacts for three phase industrial power) in the main power circuit. (Note: Large motors use high voltage and experience high in-rush current, making speed important in making and breaking contact. This can be dangerous for personnel and property with manual switches.) All contacts are held engaged by their respective electromagnets until a "stop" or "off" button is pressed, which de-energizes the lock in relay. See diagram: Motor Starters Hand-Off-Auto with Start-Stop (Note: The above description is the "Auto" position case in this diagram).

Commonly interlocks are added to a control circuit. Suppose that the motor in the example is powering machinery that has a critical need for lubrication. In this case an interlock could be added to insure that the oil pump is running before the motor starts. Timers, limit switches and electric eyes are other common elements in control circuits.

Solenoid valves are widely used on compressed air or hydraulic fluid for powering actuators on mechanical components. While motors are used to supply continuous rotary motion, actuators are typically a better choice for intermittently creating a limited range of movement for a mechanical component, such as moving various mechanical arms, opening or closing valves, raising heavy press rolls, applying pressure to presses.

1.1.3 Computer control

Computers can perform both sequential control and feedback control, and typically a single computer will do both in an industrial application. Programmable logic controllers (PLCs) are a type of special purpose microprocessor that replaced many hardware components such as timers and drum sequencers used in relay logic. General purpose process control computers have increasingly replaced standalone controllers, with a single computer able to perform the operations of hundreds of controllers. Process control computers can process data from a network of PLCs, instruments and controllers in order to implement typical (such as PID) control of many individual variables or, in some cases, to implement complex control algorithms using multiple inputs and mathematical manipulations. They can also analyse data and create real time graphical displays for operators and run reports for engineers and management.

Control of an automated teller machine (ATM) is an example of an interactive process in which a computer will perform a logic derived response to a user selection based on information retrieved from a networked database. The ATM process has a lot of similarities to other online transaction processes. The different logical responses are called scenarios. Such processes are typically designed with the aid of use cases and flowcharts, which guide the writing of the software code.

1.2 History

The earliest feedback control mechanism was used to tent the sails of windmills. It was patented by Edmund Lee in 1745.


The centrifugal governor, which dates to the last quarter of the 18th century, was used to adjust the gap between millstones. The centrifugal governor was also used in the automatic flour mill developed by Oliver Evans in 1785, making it the first completely automated industrial process. The governor was adopted by James Watt for use on a steam engine in 1788 after Watt’s partner Boulton saw one at a flour mill Boulton & Watt were building.

The governor could not actually hold a set speed; the engine would assume a new constant speed in response to load changes. The governor was able to handle smaller variations such as those caused by fluctuating heat load to the boiler. Also, there was a tendency for oscillation whenever there was a speed change. As a consequence, engines equipped with this governor were not suitable for operations requiring constant speed, such as cotton spinning.

Several improvements to the governor, plus improvements to valve cut-off timing on the steam engine, made the engine suitable for most industrial uses before the end of the 19th century. Advances in the steam engine stayed well ahead of science, both thermodynamics and control theory.

The governor received relatively little scientific attention until James Clerk Maxwell published a paper that established the beginning of a theoretical basis for understanding control theory. Development of the electronic amplifier during the 1920s, which was important for long distance telephony, required a higher signal to noise ratio, which was solved by negative feedback noise cancellation. This and other telephony applications contributed to control theory. Military applications during the Second World War that contributed to and benefited from control theory were fire-control systems and aircraft controls. The so-called classical theoretical treatment of control theory dates to the 1940s and 1950s.

Relay logic was introduced with factory electrification, which underwent rapid adaption from 1900 through the 1920s. Central electric power stations were also undergoing rapid growth and operation of new high pressure boilers, steam turbines and electrical substations created a large demand for instruments and controls.

Central control rooms became common in the 1920s, but as late as the early 1930s, most process control was on-off. Operators typically monitored charts drawn by recorders that plotted data from instruments. To make corrections, operators manually opened or closed valves or turned switches on or off. Control rooms also used colour coded lights to send signals to workers in the plant to manually make certain changes.

Controllers, which were able to make calculated changes in response to deviations from a set point rather than on-off control, began being introduced the 1930s. Controllers allowed manufacturing to continue showing productivity gains to offset the declining influence of factory electrification.

In 1959 Texaco’s Port Arthur refinery became the first chemical plant to use digital control. Conversion of factories to digital control began to spread rapidly in the 1970s as the price of computer hardware fell.


1.3 Significant applications

The automatic telephone switchboard was introduced in 1892 along with dial telephones. By 1929, 31.9% of the Bell system was automatic. Automatic telephone switching originally used electro-mechanical switches, which consumed a large amount of electricity. Call volume eventually grew so fast that it was feared the telephone system would consume all electricity production, prompting Bell Labs to begin research on the transistor.

The logic performed by telephone switching relays was the inspiration for the digital computer.

The first commercially successful glass bottle blowing machine was an automatic model introduced in 1905. The machine, operated by a two man crew working 12 hour shifts, could produce 17,280 bottles in 24 hours, compared to 2,880 bottles made by a crew of six men and boys working in a shop for a day. The cost of making bottles by machine was 10 to 12 cents per gross compared to $1.80 per gross by the manual glassblowers and helpers.

Sectional electric drives were developed using control theory. Sectional electric drives are used on different sections of a machine where a precise differential must be maintained between the sections. In steel rolling, the metal elongates as it passes through pairs of rollers, which must run at successively faster speeds. In paper making the paper sheet shrinks as it passes around steam heated drying arranged in groups, which must run at successively slower speeds. The first application of a sectional electric drive was on a paper machine in 1919. One of the most important developments in the steel industry during the 20th century was continuous wide strip rolling, developed by Armco in 1928.

Before automation many chemicals were made in batches. In 1930, with the widespread use of instruments and the emerging use of controllers, the founder of Dow Chemical Co. was advocating continuous production.

Self-acting machine tools that displaced hand dexterity so they could be operated by boys and unskilled labourers were developed by James Nasmyth in the 1840s.Machine tools were automated with Numerical control (NC) using punched paper tape in the 1950s. This soon evolved into computerized numerical control (CNC).

Today extensive automation is practiced in practically type of manufacturing and assembly process. Some of the larger processes include electrical power generation, oil refining, chemicals, steel mills, plastics, cement plants, fertilizer plants, pulp and paper mills, automobile and truck assembly, aircraft production, glass manufacturing, natural gas separation plants, food and beverage processing, canning and bottling and manufacture of various kinds of parts. Robots are especially useful in hazardous applications like automobile spray painting. Robots are also used to assemble electronic circuit boards. Automotive welding is done with robots and automatic welders are used in applications like pipelines.


1.4 Advantages and disadvantages

The main advantages of automation are:

a. Increased through output or productivity.

b. Improved quality or increased predictability of quality.

c. Improved robustness (consistency), of processes or product.

d. Increased consistency of output.

e. Reduced direct human labour costs and expenses.

f. The following methods are often employed to improve productivity, quality, or robustness.

g. Install automation in operations to reduce cycle time.

h. Install automation where a high degree of accuracy is required.

i. Replacing human operators in tasks that involve hard physical or monotonous work.

j. Replacing humans in tasks done in dangerous environments (i.e. fire, space, volcanoes, nuclear facilities, underwater, etc.)

k. Performing tasks that are beyond human capabilities of size, weight, speed, endurance, etc.

l. Economic improvement: Automation may improve in economy of enterprises, society or most of humanity. For example, when an enterprise invests in automation, technology recovers its investment; or when a state or country increases its income due to automation like Germany or Japan in the 20th Century.

m. Reduces operation time and work handling time significantly.

n. Frees up workers to take on other roles.

o. Provides higher level jobs in the development, deployment, maintenance and running of the automated processes.

The main disadvantages of automation are:

a. Causing unemployment and poverty by replacing human labour.

b. Security Threats/Vulnerability: An automated system may have a limited level of intelligence, and is therefore more susceptible to committing errors outside of its immediate scope of knowledge (e.g., it is typically unable to apply the rules of simple logic to general propositions).


c. Unpredictable/excessive development costs: The research and development cost of automating a process may exceed the cost saved by the automation itself.

d. High initial cost: The automation of a new product or plant typically requires a very large initial investment in comparison with the unit cost of the product, although the cost of automation may be spread among many products and over time. In manufacturing, the purpose of automation has shifted to issues broader than productivity, cost, and time.

1.5 Health and environment

The costs of automation to the environment are different depending on the technology, product or engine automated. There are automated engines that consume more energy resources from the Earth in comparison with previous engines and those that do the opposite too. Hazardous operations, such as oil refining, the manufacturing of industrial chemicals, and all forms of metal working, were always early contenders for automation.

1.6 Convertibility and turnaround time

Another major shift in automation is the increased demand for flexibility and convertibility in manufacturing processes. Manufacturers are increasingly demanding the ability to easily switch from manufacturing Product A to manufacturing Product B without having to completely rebuild the production lines. Flexibility and distributed processes have led to the introduction of Automated Guided Vehicles with Natural Features Navigation.

Digital electronics helped too. Former analogue-based instrumentation was replaced by digital equivalents which can be more accurate and flexible, and offer greater scope for more sophisticated configuration, parameterization and operation. This was accompanied by the field bus revolution which provided a networked (i.e. a single cable) means of communicating between control systems and field level instrumentation, eliminating hard-wiring.

Discrete manufacturing plants adopted these technologies fast. The more conservative process industries with their longer plant life cycles have been slower to adopt and analogue-based measurement and control still dominates. The growing use of Industrial Ethernet on the factory floor is pushing these trends still further, enabling manufacturing plants to be integrated more tightly within the enterprise, via the internet if necessary. Global competition has also increased demand for Reconfigurable Manufacturing Systems.

1.7 Automation tools


Engineers can now have numerical control over automated devices. The result has been a rapidly expanding range of applications and human activities. Computer-aided technologies (or CAx) now serve the basis for mathematical and organizational tools used to create complex systems. Notable examples of CAx include Computer-aided design (CAD software) and Computer-aided manufacturing (CAM software). The improved design, analysis, and manufacture of products enabled by CAx has been beneficial for industry.

Information technology, together with industrial machinery and processes, can assist in the design, implementation, and monitoring of control systems. One example of an industrial control system is a programmable logic controller (PLC). PLCs are specialized hardened computers which are frequently used to synchronize the flow of inputs from (physical) sensors and events with the flow of outputs to actuators and events.

Fig 1.1 - Automation

Chapter – 2SUPERVISORY CONTROL AND DATA ACQUISITION (SCADA)


2.1 WHAT IS MEANT BY SCADA?

SCADA stands for supervisory control and data acquisition. As the name indicates it is not a full control system, but rather focuses on the supervisory level. As such , it is a purely software package that is positioned on the top of hardware to which it is interfaced in general via programmable logic controllers (PLC’s ), or other commercial hardware modules.

S - Supervisory (we can see process on monitor)

C - Control (when setup is complete we can also control the process)

A - And

D - Data (database can also be saved in plc or pc memory)

A - Acquisition

SCADA programs are used in industrial process control applications for centralized monitoring and recording of pumps, tank levels, switches, temperatures etc. SCADA systems are also referred to as HMI (Human Machine Interfaces), or the less politically correct MMI (Man Machine Interfaces).

A SCADA program normally runs on a PC and communicates with external instrumentation and control devices. Communications methods can be via direct serial link, radio, modem, field bus or Ethernet links. If a mixture of instruments with differing communication interfaces and protocols need to be connected, then converters can be used. SCADA is often used on remote data acquisition systems where the data is viewed and recorded centrally.

2.2 History of SCADA: -

SCADA systems have evolved in parallel with the growth and sophistication of modern computing technology. The following sections will provide a description of the following three generations of SCADA systems: -

2.2.1 First Generation SCADA (Monolithic):-

When SCADA systems were first developed, the concept of computing

In general, centered on “mainframe” systems. Networks were generally non-existent, and centralized system stood alone. As a result, SCADA systems were standalone systems with virtually no connectivity to other systems.


The Wide Area Networks (WANs) that were implemented to communicate with remote terminal units (RTUs) were designed with a single purpose in mind that communicating with RTUs in the field and nothing else. In addition, WAN protocols in use today were largely unknown at the time.

Redundancy in these first generation systems was accomplished by the use of two Identically equipped mainframe systems, a primary and a backup Connected at the Bus level the standby system’s primary function was to monitor the primary and takeover in the event of a detected Failure. This type of standby operation meant that little or no Processing was done on the standby system.

Fig 2.1:- First Generation of SCADA

2.2.2 Second Generation of SCADA (Distributed):-

The next generation of SCADA systems took advantage of developments and improvement in system miniaturization and Local Area Networking (LAN) technology to distribute the processing across multiple systems. Multiple Stations, each with a specific function, were connected to a LAN and shared Information with each other in real-time. These stations were typically of the Mini- computer class, smaller and less expensive their first generation processors.

Fig 2.2. –

Second Generation of SCADA

Distribution of system functionality across network-connected systems served not only to increase processing power, but also to improve the redundancy and reliability of the System as a whole. Rather than the simple primary/standby failover scheme that was Utilized in many first generation systems, the distributed architecture often kept all Stations on the LAN in an online state all of the time. For example, if an HMI station were to fail, another HMI station could be used to operate the system, without waiting failover from the primary system to the secondary.


2.2.3 Third Generation of SCADA (Networked):-

The current generation of SCADA master station architecture is closely related to that of the second generation, with the primary difference being that of an open system architecture rather than a vendor controlled, proprietary environment. There are still multiple networked systems, sharing master station functions. There are still RTUs utilizing protocols that are vendor-proprietary.

The major improvement in third generation SCADA systems comes from the use of WAN protocols such as the Internet Protocol (IP) for communication between the master station and communications equipment. This allows the portion of the master station that is responsible for communications with the field devices to be separated from the master station “proper” across a WAN. Vendors are now producing RTUs that can communicate with the master station using an Ethernet connection.

Fig:-2.3 Third Generation of SCADA

2.3 SCADA System Software:-

The typical component of SCADA system with emphasis on the SCADA software are indicated in shown in figure.


Fig:-2.4 SCADA System

Typical key features expected of the SCADA software are listed below. These

Features depend on the hardware to be implemented.

2.4 SCADA Key Features: -

2.4.1 User Interface: -

Keyboard

Mouse

Trackball

Touch screen

2.4.2 Graphics Displays: -

Customer-configurable, object orientated and bit mapped.

Unlimited number of pages.


Fig 2.6 – Scada Alarm

Resolution: up to 1280 x 1024 with millions of colours.

Fig: -2.5 - SCADA Project

2.4.3 Alarms: -

• Client server architecture.

• Time stamped alarms to 1 millisecond precision (or better).

• Single network Acknowledgment and control of alarms.

• Alarms shared to all clients.

• Alarms displayed in chronological order.

• Dynamic allocation of alarm pages.

• User-defined formats and colours.

• Up to four adjustable trip points for each analog alarm.

• Deviation and rate of change monitoring for analog alarms.

• Selective display of alarms by category (256 categories).

• Historical alarm and event logging.

• Context-sensitive help.

• On-line alarm disable and threshold modification.

• Event-triggered alarms.

• Alarm-triggered reports.

• Operator comments that can be attached to alarms.


Fig 2.7 – SCADA Trends

2.4.4 Trends: -

• Client server architecture.

• True trend printouts (not screen dumps).

• Rubber band trend zooming.

• Export data to DBF, CSV files.

• X/Y plot capability.

• Event based trends.

• Pop-up trend display.

• Trend grid lines or profiles.

• Background trend graphics.

• Real-time multi-pen trending.

• Short and long term trend display.

• Length of data storage and frequency of monitoring that can be specified on a per-point basis archiving of historical trend data.

• On-line change of time-base without loss of data.

• On-line retrieval of archived historical trend data.

• Exact value and time that can be displayed.

• Trend data that can be graphically represented in real time.

2.4.5 RTU (and PLC) Interface: -

• All compatible protocols included as standard.


Fig 2.8 – Scada Database

• DDE drivers supported.

• Interface also possible for RTUs, loop controllers, bar code readers and other equipment.

• Driver toolkit available.

• Operates on a demand basis instead of the conventional predefined scan method.

• Optimization of block data requests to PLCs.

• Rationalization of network user data requests.

• Maximization of PLC highway bandwidth.

2.4.6 Scalability: -

Additional hardware can be added without replacing or modifying existing Equipment. This is limited only by the PLC architecture (typically 300 to 40,000 Points).

2.4.7 Access to Data: -

• Direct, real-time access to data by any network user.

• Third-party access to real-time data, e.g. Lotus 123 and EXCEL Network DDE

• DDE compatibility: read, write and exec.

• DDE to all IO device points.

• Clipboard.

2.4.8 Database: -

• ODBC driver support.

• Direct SQL commands or high level reporting.

2.4.9 Networking: -


• Supports all NetBIOS compatible networks such as NetWare, LAN Manager, and Windows for Workgroups, Windows NT (changed from existing NT).

• Support protocols NetBEUI, IPX/SPX, TCP/IP and more.

• Centralized alarm, trend and report processing - data available from anywhere in the network.

• Dual networks for full LAN redundancy.

• No network configuration required (transparent).

• May be enabled via single check box, no configuration.

• LAN licensing based on the number of users logged onto the network, not the number of nodes on the network.

• No file server required.

• Multi-user system, full communication between operators.

• RAS and WAN supported with high performance PSTN dial up support.

2.4.10 Fault Tolerance and Redundancy: -

• Dual networks for full LAN redundancy.

• Redundancy that can be applied to specific hardware.

• Supports primary and secondary equipment configurations.

• Intelligent redundancy allows secondary equipment to contribute to processing load.

• Automatic changeover and recovery.

• Redundant writes to PLCs with no configuration.

• Mirrored disk I/O devices.

• Mirrored alarm servers.

• Mirrored trend servers.

• File server redundancy.

• No configuration required, may be enabled via single check box, no configuration.

2.4.11 Client/Server Distributed Processing: -


• Open architecture design.

• Real-time multitasking.

• Concurrent support of multiple display nodes.

• Access any tag from any node.

• Access any data (trend, alarm, report) from any node.

2.5 Application of SCADA: -

• SCADA is widely used in different areas from chemical, gas, water, communications and power systems. The list of applications of SCADA can be listed as follows. -

2.5.1 Electric power generation, transmission and distribution: -

Electric utilities use SCADA systems to detect current flow and line voltage, to monitor the operation of circuit breakers, and to take sections of the power grid online or offline.

2.5.2 Water, Waste Water Utilities and Sewage: -

State and municipal water utilities use SCADA to monitor and regulate water flow, reservoir levels, pipe pressure and other factors.

2.5.3 Buildings, facilities and environments: -

Facility managers use SCADA to control HVAC, refrigeration units, lighting and entry systems.

2.5.4 Oil and Gas Trans & Distributions:

2.5.5 Wind Power Generation

2.5.6 Communication Networks

2.5.7 Industrial Plans and Process Control:

2.5.8 Manufacturing: -

SCADA systems manage parts inventories for just-in-time manufacturing, Regulate industrial automation and robots, and monitor process and quality control.


Fig 2.9 – Scada Project: Sewage Water Treatment

2.5.9 Mass transit and Railway Traction: -

Transit authorities use SCADA to regulate electricity to subways, trams and trolley buses; to automate traffic signals for rail systems; to track and locate trains and buses; and to control railroad crossing gates.

2.5.10 Traffic signals: -

SCADA regulates traffic lights, controls traffic flow and detects out-of-order.


Fig 3.1 – PLC

Chapter-3Programmable Logic Controller (PLC)

3.1 What is meant by Programmable Logic Controller...?

• A PROGRAMMABLE LOGIC CONTROLLER (PLC) is an industrial computer control system that continuously monitors the state of input devices and make decisions based upon a custom program to control the state of output devices.

• It is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact.

• Almost any production process can greatly have enhanced using this type of control system, the biggest benefit in using a PLC is the ability to change and replicate the operation or process while collecting and communicating vital information.

• Another advantage of a PLC is that it is modular. I.e. you can mix and match the types of input and output devices to best suit your application.

3.2 History of PLC’s

• The first Programmable Logic Controllers were designed and developed by Modicon as a relay replacer for GM and Landis.

• The primary reason for designing such a device was eliminating the large cost involved in replacing the complicated relay based machine control systems for major U.S. car manufacturers.

• These controllers eliminated the need of rewiring and adding additional hardware for every new configuration of logic.

• The first PLC, model 084, was invented by Dick Morley in 1969.

• The first commercial successful PLC, the 184, was introduced in 1973 and was designed by Michel Greenberg.

• Communications abilities began to appear in approximately 1973. The first such system was Modicon's Modbus. The PLC could now talk to other PLCs and they could be far away from the actual machine they were controlling.


3.3 What is inside a PLC.?

• The PLC, being a microprocessor based device, has a similar internal structure to many embedded controllers and computers. They consist of the CPU, Memory and I/O devices. These components are integral to the PLC controller. Additionally, the PLC has a connection for the Programming and Monitoring Unit or to connect to other microprocessor, memory integrated circuits, and circuits necessary to store and retrieve information from memory. It also includes communication ports to the peripherals, other PLC’s or programming terminals. The job of the processor is to monitor status or state of input devices, scan and solve the logic of a user program, and control on or off state of output devices.

• RAM or Random Access Memory is a volatile memory that would lose its information if power were removed, hence some processor units are provided with battery backup. Normally CMOS (Complementary Metal Oxide Semiconductor) type RAM is used.

• ROM is a non-volatile type of memory. This means it stores its data even if no power is available. This type of memory information can only be read, it is placed there for the internal use and operation of processor units.

• EEPROME or Electrically Erasable Programmable Read Only Memory is usually an add on memory module that is used to back up the main program in CMOS RAM of the processor. In many cases, the processor can be programmed to load the EEPROM’S program to RAM, if RAM is lost or corrupted.

3.4 INPUT/OUTPUT MODULE

• Input Module • Input modules interface directly to devices such as switches and temperature sensors. Input modules convert many different types of electrical signals such as 120VAC, 24VDC, or 4-20mA, to signals which the controller can understand. Since all electrical systems are inherently noisy, electrical isolation is provided between input and processor. The component most often used for this purpose is opt coupler. Input signal from the field devices are usually 4 to 20 ma or 0-10 V.


Fig 3.2 – PLC Scan

• Output module interface directly to devices such as motor starters and lights Output modules take digital signals from the PLC and convert them to electrical signals such as 24VDC and 4 mA that field devices can understand. D to A conversion is carried out in their modules. Usually Silicon Controlled Rectifier (SCR), triac, or dry contact relays are used for this purpose. Normally the output signal is 0-10 V or 4-20 ma.

3.5 Operation of PLC

PLC operates by continually scanning the program and acting upon the instructions, one at a time, to switch on or off the various outputs. In order to do this PLC first scans all, the inputs and stores their states in memory. Then it carries out program scan and decides which outputs should be high according to the program logic.

Then finally it updates these values to the output table, making the required outputs go high.

At his point PLC checks its own operating system and if everything is ok, it goes back to scanning inputs all over again.

3.6 PLC SCAN CYCLE

Whenever a program is executed in a PLC, before changing any output state, the processor scans the input table and the entire program, which gives rise to states of the output devices according to the program logic. These values are then updated to the output table making the devices connected to the output module on or off. Hence PLC scan cycle consists of three steps shown in the block diagram.

SCAN TIME

Time taken by plc to execute these three steps (Checking Input status, Executing Program, Updating Output Status) is denoted by its scan time.


Fig 3.3 – PLC Hardware

3.7 COMMUNICATION

• There are several methods to communicate between a PLC and a Programmer or even between two PLC’s.

• PLCs have built in communications ports, usually 9-pin RS232, RS-485, TTY but optionally EIA-

485 or Ethernet. Mod bus, BACnetor DF1 is usually included as one of the communications protocols. Other options include various field buses such as DeviceNet or Profibus.

• Most modern PLCs can communicate over a network to some other system, such as a computer running a SCADA (Supervisory Control and Data Acquisition) system or web

3.8 Programming Languages used to Program a PLC

• While Ladder Logic is the most commonly used PLC programming language, but it is not the only one. Following table lists some of the Languages that are used to program a PLC.

• Ladder Diagram (LD).

• Functional block Diagram (FBD)

• Structured Text (ST)

• Instruction List (IL)

• Sequential Functional Chart (SFC)


Fig 4.1 – PLC Process

Chapter-4Micrologix 1000 PLC System

4.1 Introduction of Micrologix 1000 PLC

• A Micrologix 1000 is a programmable logic controller—an industrial computer that controls a machine or process. A PLC interfaces with the field input and output devices that are part of a control application. Then, through the control program stored in its memory, the PLC uses the data supplied by the input devices to manipulate or control the output devices.

• The Micrologix 1000 programmable logic controller may appear to be like any other PLC, but it has special features, specifications and capabilities that make it a unique tool for implementing process or machine control.

4.2 PLC Components: -

• A PLC is made up of two basic components: -

• The input/output (I/O) system

• The central processing unit (CPU)

• The input/output system is the part of the PLC that physically connects to devices in the outside world.

• The central processing unit on the other hand, is where the PLC stores all of its data and does all of its computer processing. Each of the components of a PLC has specific functions.

• Input/output System The input/output system is made up of two components, the input interface and the output interface.

• An input interface is a bank of terminals that physically connects input devices, like push buttons and limit switches, to a PLC. These input devices provide data to the


Fig 4.2 – PLC Block

Fig 4.3 – PLC wiring

PLC. The role of an input interface is to translate data from the inputs into a form that the PLC’s central processing unit can understand.

• An output interface is a bank of terminals that physically connects output devices, such as solenoids and motor starters, to a PLC. These output devices receive control data from a PLC. The role of an output interface is to translate data from the PLC’s CPU into a form that the output devices can understand.

The CPU is made up of three parts: -

The memory system

The Processor

The Power Supply

4.3 Configurations: -

• A Micrologix 1000 PLC comes in many configurations. These configurations differ by: -

• The number of inputs and outputs

• The type of power supply

• The type of I/O interfaces

4.4 Connections or Wiring:-


Fig 4.4 – PLC input / output

4.5 Inputs and Outputs: -

• The number of inputs and outputs determines the size of a Micrologix PLC. The Micrologix 1000 comes in two sizes: 16 I/O and 32 I/O. A 16 I/O Micrologix can connect with up to 10 input devices and 6 output devices 32 I/O model can connect with up to 20 input devices and 12 output devices (see Figure 1-16). The size of a Micrologix 1000 should be chosen based on the amount of I/O required for its application.

4.6 Power Supply: -

• The Micrologix 1000 also has two types of power supplies. These are 24 VDC (volts DC) and 120/240 VAC (volts AC). The power supply should be chosen based on the power requirements and the power availability for the application.

4.7 I/O Interfaces: -

• A Micrologix 1000 PLC has many options available for both its input and output interfaces. A Micrologix 1000 can have one of two types of input interfaces, either 24 VDC or 120VAC. These input interfaces allow the Micrologix 1000 to connect with either 24 VDC or 120 VAC input devices, respectively. Just as a Micrologix 1000 has a choice of inputs, it has a choice of outputs as well. The Micrologix 1000 uses three types of outputs: -

• Relay

• Transistor

• Triac

4.8 Addressing of PLCs: -

• I :e.s/b

• O:e.s/b

• Nf: 3/b


Fig 4.5 – Ladder Language

Where -

a) I = Input

b) = Output

c) N = Integer File

d) : = Element delimiter

e) e = Slot number

f) f = File number

g) . = Word delimiter

Only required when word number is used.

a) s = word number

b) / = Bit delimiter

c) b = Terminal number

4.9 Types of Languages: -

The three types of programming languages used in PLCs are: -

a) Ladder Language: -

The programmable controller was developed for easeof programming using existing relay ladder symbols and expressions to represent the program logic needed to control the machine or process. The resulting programming language, which used these original basic relay ladder symbols, was given the name ladder language .

.


Fig 4.6 – Boolean language

Fig 4.7 – Grafcet Language

b) Boolean: -

Some PLC manufacturers use Boolean language, also called Boolean mnemonics, to program a controller. The Boolean language uses Boolean algebra syntax to enter and explain the control logic. That is, it uses the AND, OR and NOT logic functions to implement the control circuits in the control program.

c) Grafcet: -

Grafcet (Graphe Fonctionnel de Commande Étape Transition) is a symbolic, graphic language, which originated in France that represents the control program as steps or stages in the machine or process. In fact, the English translation of Grafcet means “Step transition function charts.”


Fig 4.8 – Allen- Bradley PLC

4.10 Advantages: -

Fast processing allows for typical through put time of 1.5 ms for a 500-instruction program.

Built-in EEPROM memory retains all of your ladder logic and data if the controller loses power, eliminating the need for battery back-up or separate memory module.

Controllers that have 24V dc inputs include a built-in high-speed counter (6.6k Hz).

Multiple input and output commons allow you to use the controller for either sinking or sourcing input devices and provide isolated commons for multi-voltage output applications.

Adjustable DC input filters allow you to customize the input response time and noise rejection to meet your application needs RS-232 communication channel allows for simple connectivity to a personal computer.

Peer-to-peer messaging capability allows you to network up to 32 controllers.

RTU slave protocol support using DF1 Half-Duplex allows up to nodes to communicate with a single master using radio modems, leased-line modems, satellite uplinks.

Regulatory agency certifications for world-wide market (CE, C-Tick, UL, c-UL, including Class I Division 2) Hazardous Location.


Fig 5.1 – TON

Chapter-5Ladder Programming

5.1 Introduction: -

Now that the PLC has been introduced, let us move on to programming the PLC. The first, and still most popular programming language, is ladder logic. The language is developed from the electromechanical relay system-wiring diagram. After describing the basic symbols for the various processors covered by this text, they are combined into a ladder diagram. The subsequent section details the process of scanning a program and accessing the physical inputs and outputs. Programming with the normally closed contact is given particular attention because it is often misapplied by novice programmers. To solidify these concepts, the start/stop of a physical device is considered. Start/stop is a very common PLC application and occurs in many other contexts.

5.2 Instructions: -

Timer ON: -

The TON instruction to turn an output on or off after the timer has been on for a preset time interval. The TON instruction begins to count time base intervals when rung conditions becomes.

Addressing Examples: -

T4:0/15 or T4:0/EN Enable bit

T4:0/14 or T4:0/TT Timer timing bit

T4:0/13 or T4:0/DN done bit

T4:0.1 or T4:0.PRE Preset value of the timer

T4:0.2 or T4:0.ACC Accumulated value of the timer

T4:0.1/0 or T4:0.PRE/0 Bit 0 of the preset value

T4:0.2/0 or T4:0.ACC/0 Bit 0 of the accumulated value


Fig 5.2 – TOF

Fig 5.3 – RTO

Fig 5.4 – CTU

Fig 5.5 – CTD

Timer OF:-

The TOF instruction to turn an output on or off after its rung has been off for a preset time interval. The TOF instruction begins to count time base intervals when the rung makes a true-to-false transition.

Retentive Timer (RTO):-

The RTO instruction to turn an output on or off after its timer has been on for a preset time interval. The RTO instruction is a retentive instruction that begins to count time base intervals when rung conditions become true .

Counter UP:-

The CTU is an instruction that counts false-to-true rung transitions. Rung transitions can be caused by events occurring in the program (from internal logic or by external field devices) such as parts traveling past a detector or actuating a limit switch.

Counter DOWN:-

The CTD is an instruction that counts false-to-true rung transitions. Rung transitions can be caused by events occurring in the program such as parts

Traveling past a detector or actuating a limit switch .


Fig 5.6 – OR gate

5.3 Logic Gates in Ladder Programming:-

1) OR Gate –

2) AND Gate -


Truth Table of OR Gate OR Gate Circuit Using Relay

OR Gate Implement Using Ladder Programming

Truth Table of AND Gate AND Gate Circuit Using Relay

A B Lamp

off off on on

off on off on

off on on on

A B Lamp

off off on on

off on off on

off off off on

Fig 5.7 – AND Gate

Fig 5.8 – SCADA Software


AND Gate Implement Using Ladder Programming

Chapter-6Conclusion

In my two months of training I acquired knowledge about automation industries and how work in industries. During this time, I learnt about the programming in automation. I got some information about plc and how we work on it. I learned the programming on different plc by using different plc software’s.

I also learnt about basics of SCADA and how it useful in industries. I also learnt about connection of plc and SCADA through contactors and relay. I also got brief knowledge about drives.

Companies that dealing with automation industries using plc and SCADA needs a that type of employees .so the knowledge that I got during my training is helpful in future for employment.


Chapter-7Bibliography

www.google.com

www.wikipedia.com

www.rockwell.com

www.plcmanual.com

www.plc.net

www.Automation.com


http://www.automation.com/

http://www.plc.net/

http://www.plcmanual.com/

http://www.rockwell.com/

http://www.wikipedia.com/

http://www.google.com/

Plc & scada Training Report

Engineering

Transcript of Plc & scada Training Report