Automation

INTRODUCTION

 What is Automation ?

 Overview of Automation

 Motivation

 Automation in industry

 Examples from different industry sectors

What is automation ?

          Benefit of automation is that it saves labor; however, it is also used to save energy and materials and to improve quality, accuracy and precision.


           Automation is basically the delegation of human control function to technical equipment for

1. Increasing productivity

2. Increasing robustness (consistency)

3. Reducing direct human labor costs and expenses.

4. Increasing quality 

History of automation

 Manual Control

 Pneumatic Control

 Hard wired logic Control

 Electronic Control using Logic Gates

 Programmable Logic Controller

1. Manual Control

           All the actions related to process control are taken by the operators manually.

Disadvantage

           Likely human errors and consequently its effect on quality of final product.
           The production, safety, energy consumption and usage of raw material are all subject to the correctness and accuracy of human action.

2.  Pneumatic Control

           Industrial automation, with its machine and process control, had its origin in the 1920s with the advent of "Pneumatic Controllers“.

            Actions were controlled by a simple manipulation of pneumatic valves, which in turn were controlled by relays and switches.

Disadvantage

            Bulky and Complex System

            Involves lot of rework to implement control logic

            Longer project time

3. Hard wired logic Control

            The contactor and relays together with hardware timers and counters were used in achieving the desired level of automation

Disadvantage

             Bulky panels

             Complex wiring

             Longer project time
             Difficult maintenance and troubleshooting

 4. Electronic Control using Logic Gates

             In 1960s with the advent of electronics,  the logic gates started replacing the relays and 
auxiliary contactors in the control circuits.

             The hardware timers & counters were replaced by electronic timers.

Advantage

             Reduced space requirements

             Energy saving
             Less maintenance & greater reliability 

Disadvantage

             Changes in control logic not possible
             More project time

5.  Programmable Logic Controller

             In 1970s with the coming of microprocessors and associated peripheral chips, the whole process of control and automation  underwent a radical change.

             Instead of achieving the desired control or automation through physical wiring of control devices, in PLC it is achieved through  a program or say software.

             The programmable controllers have in recent years experienced an unprecedented growth as universal element in Industrial Automation.
            It can be effectively used in applications ranging from simple control like replacing small number of relays to complex  automation problems. 

Advantages of PLCs
          Reduced space

          Energy saving

          Ease of maintenance

          Economical

          Greater life & reliability

          Tremendous flexibility

          Shorter project time

          Easier storage, archiving and documentation

Industrial automation main components

Field instruments
Control hardware
Control software

Automation : Typical installation...

Automation : Typical installation...

Sensors or Transducers (Field Instruments)

Sensors are used to sense the changes in physical parameter like Temperature, Level, Flow, Humidity, Pressure and many others..

Transducers are used to convert not electrical quantity to electrical signals

Hence it concludes, sensors and transducers are placed in field to sense the physical parameters and send the electrical signal of respective changes to control rooms.

These signal are either digital or analog signals for example, Ohm(RTD), mv(Thermocouple),  standard 4-20mA signal, etc.

Widely used field instruments in industries

Flow transmitters (Orifice, Ventury, Electromagnetic flow meter etc)

Pressure transmitters (Bourdon gauge, Bellows, Diaphragm, etc)

Temperature transmitters (Thermocouple, RTD, Thermister, etc)

Level Transmitter (Ultrasonic transmitter, Radar type, capacitive type)

pH transmitter

Conductivity Meter...etc

Famous manufacturing companies (Field instruments)

Fisher Rosemount
Yokogawa
Endress+Hauser
Forbes Marshall
Honeywell ABB

Control hardware

Standalone PID Controllers
Programmable logic controllers
Distributed control system 

1. Standalone PID Controllers

These are the small controlling hardware which fulfill the requirement of closed loop.

This can be installed in field or in control room

Every companies have variations in programming patterns to setup PID configuration 

Typical installation of standalone PID controller

Master slave communication with RS485

Famous manufacturing companies in PID controllers

ABB
Yokogawa
Moore
Forbes Marshall
Honeywell
Eurotherm
ASCON

2.  Programmable logic controllers

PLCs

             A programmable logic controller (PLC), or programmable controller is an industrial digital computer which has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines,  or robotic devices, or any activity that requires high reliability control and ease of programming and process fault diagnosis.

What is inside PLC ?

Architecture of PLC

A programmable logic controller (PLC),  is a like a microcontroller which is used for doing so many applications.

It basically consist of

1. CPU with processor and program memory

2. Power supply

3. Input module

4. Output module

5. Control  bus

1. Parts of Delta PLC

2. Parts of Allen Bradley PLC

3. Parts of Siemens PLC




4. Parts of Zelio Schneider electric PLC

Distribution of I/O's through controller

Distributed control system (DCS)

General architecture of DCS

System cabinets and Marshalling cabinets of DCS

System and Marshalling cabinet arrangement

Various DCS and Hybrid DCS providing companies

DCS

1. Yokogawa (Centum VP)

2. Honeywell (EPKS)

3. Emerson (Delta V)

4. Forbes Marshall

Hybrid DCS

1. Allen Bradley (Compact logix and control logix)

Various Communication protocol used in DCS or PLC systems and its hierarchy

LAN (Ethernet)

Modbus, CAN, Serial communication

OPC (OLE for Process Control)

Control NET

Foundation Field bus

Profibus (DP,PA)

Device NET

Various languages used in PLC and DCS

Ladder Logic ( LAD/LD)

Function Block Diagram (FBD)

Sequential Function Chart (SFC)

Structured Text (ST)

Instruction List (IL )

Supervisory Control and Data Acquisition software (SCADA)

                   SCADA (supervisory control and data acquisition) is a category of software application program for process control, the gathering of data in real time from remote locations in order to control equipment and conditions.

Features of typical SCADA software

    Dynamic process graphic

    Real-time and Historical trending

    Alarms

    Recipe Management

    Security

    Device connectivity

    Script for logic development

    Database connectivity

Displays used for monitoring in SCADA systems

Some SCADA software available in market

Intouch (Wonderware factory suit)

Wincc (Siemens)

Simplicity (GE Fanuc)

RS View32 (Allen Bradley)

Flow of project in industry

Core branches/career of Instrumentation and its scope in Industry

JOB OPTIONS

 EPC

Engineering Procurement and construction

Designing of total plant

Automation work includes in EPC companies

Designing of P&ID drawings

 Automation

Designing of the Automation system

Erection and Commissioning

Maintenance and Troubleshooting of existing system

Author : Tushar

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