industrial automation 4

8/12/2019 Industrial Automation 4

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Automation Basics


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What one will learn ?

What are the basic elements of Automation ?

Why automation is necessary ?

What are the different technologies available forthe automation.?

Where automation exists ?

What are the different controllers ?

What is SCADA and DCS ?

How communication is playing a vital role in theprocess of Automation ?

What are the different protocols used inAutomation?


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Contents: What is AutomationRole of Automation in the different industries

Why Automation ? ( Advantages)

Basic elements of Automaton Sensors LVDT,Thermostat,Thermistor ,pressure CT,PT,

Limit switches,Magntic Pick Up,Capacitive sensors etc

Controllers and controller based systems

Actuators Relays. Solenoids.

Types of Controllers Proportional,PI ,PID,

Categories of controllers DCS & SCADA What is SCADA

How communication has enhanced automation.

Common Protocols CAN ,MODBUS,PROPHI, Substation automationprotocol 61850

When to go for Automation ?

Design of Automation system Limitations / Disadvantages of Automation

Automation Myths Impact of Automation

How automation affects economics ?

Queries


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What is Automation ?

The dictionarydefines automationas Thetechnique of making anapparatus, a process, or asystem operate automatically.

Automation federation defineautomation as

The creation and application oftechnology to monitor andcontrol the production anddelivery of products andservices.

Automation means use of Availabletechnologies to reduce the need ofHuman work.

Automation is a step beyond

mechanization.

Mechanization provides humanoperators machinery to assistthemselves with the muscularrequirements of work

WhileAutomation greatly decreases the need

for human sensory and mentalrequirements as well. .


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Quality

Productivity

Manpower CostPlant

Total Automation ManufacturingCompetitiveness

Solution

Automation:Automation is basically the delegation of human control

function to technical equipment for


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Automation cycleSense the Inputs

Process the Logic

Give the Outputs

Outputs

Machine

or

Process

Controller

Inputs


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History of Automation

Manual control

Pnumatic control

Hard wired Logic Control

Electronic control using Logic gates

Programmable logic controller

Microcontrller based embedded

controllers

Cluster of controllers and

Master controller at Remote end.

Modern world

Ancient world


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Major Mile stones in Technologies

Ancient world

( 8000BC to 330 )

The middle agethrough 1599

The age of scientificrevolutions1600-1790

The industrial Revolution

1700-1920

The electrical age

1891 to 1934

The atomic and electronic age1935 into 21stcenturyout of which last 20 yearsbelong to COMMUNICATIONand INFORMATION ERA

Invention of Wheel

Discoveries of various metals

Invention of Glass

Discovery of Electricity

Invention of Telegraphy/Telephone

Invention of Electric Motor

Invention of Transistor 1948

Invention of Microprocessor

Invention of MobileTechnology

Invention of InternetTechnology


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Range of Technologies involved in AUTOMATION

Automation involves a very broad range of technologiesincluding

1. Robotics2. Expert systems

(an expert systemis a computer system that emulates the decision-making ability of a human expert )

3 Telemetry and communications

4 Electro-optics

Electro-optics is a branch of technology involving components,devices and systems which operate by modification of the opticalproperties of a material by an electric field.

5 Cyber security,

( protecting your personal information or any form of digital assetstored in your computer or in any digital memory device)

6 Process measurement and control,

7 Sensors,

8 wireless applications, systems integration, test measurement, andmany, many more.


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Where Automation exists ?

Automation encompasses many vital elements,

systems, and job functions. Manufacturing,including food and pharmaceutical, chemical and

petroleum, pulp and paper

Transportation, including automotive, aerospace, and rail

Utilities, including water and waste water, oil and gas, electric

power, and telecommunications

Defense

Facility operations, including security, environmental control,energy management, safety, and other building automation

..Andmany others


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AUTOMATION IS EVERYWHERE

Automation is in all

functions and places

Aerospace

Automotive

Chemical and Petroleum

Computer Technology

Construction and Design Electro-Optics

Environmental

Food and Pharmaceutical

Glass and Ceramics

Management

Marketing and Sales

Mining and Metals

Mining and Metals

Nuclear Power Distribution

Process Measurement andControl

Pulp and Paper

Robotics and Expert Systems

Safety

Sensor Technology

Systems Integration

Telemetry andCommunications

Test Measurement Textiles

Water and Waste water

Wireless Application

.


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Impact of Automation:

Automation has a significant

impact in the wide range of

industries including

Manufacturing industries

Automation has beenresponsible for the shift in the

world economy from industrial

jobs to service jobs in the 20th

and 21st centuries.

Once omnipresent telephone

operators have seized to exist

as telephone exchanges are

automated.

ATM have reduced the need

for bank visits to obtain cash

and carry out transactions.


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Impact of Automation:

As a result of increase in

Automation and (which is

ever increasing almost

every field as a result of

ease in use of newTechnologies)

the nature of jobs is getting

affected .

Telephone operators

Stock market agents

Railroad brake signal and

switch operators Shoe and leather workers

Photographic process

workers and processing

machine operators Model makers and

pattern makers


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How much Automation ?

Automation represents one of the major trends of 20thcentury as inmany cases automation has provided extended system functionalitywell beyond existing human capabilities.

Contrary to the implication of the term Automated humans haveremained a critical part of most automated systems as mostautomation has been piece meal covering certain functions but notall functions.Human beings have remained in the system asintegratorsmonitoring the automation for some functions andperforming others themselves

Full automation of the task may be technically possible but it maynotbe desirable if the performance of the joint human- machinesystem is to be optimized.Intermediate levels of Automation may bepreferable for certain tasks in order to keep human operatorssituation awareness at a higher level and allow them to performcritical functions


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Level of Control

One way to minimize the negative effect of Automation is

to devise implementation schemesthat keep human

beings actively involved in the decision making loop

while simultaneously reducing the load associated with

doing everything manually


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Levels of control and Automation:

(adapted from Endsley and kiris,1995)

LEVEL OF AUTOMATIONROLE

HUMAN SYSTEM

NONE 1 Decide Act ---

Decision support 2 Decide Act Suggest

Consensual Artificial

intelligence (AI) 3 Concur Decide Act

Monitored AI 4 Veto Decide Act

Full automation 5 --- Decide Act

1 Manual system

5 Fully automatic system


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EXAMPLES OF AUTOMATION


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Common Examples of AutomationDay to Day life ATM

Starting of the vehicle

Automatic washingMachine

Electrically driven Pump

UPS, Canopy (powersupply Back up

Industry

Painting Robots in theautomobile mfg

industry Soldering Machines

DCS DistributedControl Systems

SCADA

AMF Generators


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Home Automation


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Subsystems of Home Automation:

Hot water systems.

Appliances. Systems

Home office, home entertainment and other electronicequipments.

Lighting. Heating and cooling/air conditioning systems.

Fans and air pumps/heat shifters.

Powered window blinds, shutters and awnings.

Powered vents and window openings.

Water pumps, pool pumps .

Garage doors.

Security systems.


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Why Automation is required ?

Increase in comfort

More safety

Improve the quality and precision. To do the job for which human beings will

not have the capacity.

To avoid monotonous work


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Sensors

What is a sensor ?

Sensor is a device which measures a physical

quantity.

Temperature sensor (Input to thermometer

/Temperature indicator)

Level sensor input to Fuel gauge

Proximity sensor, Pressure sensor

Photoelectric sensor LDR / opto coupler /photodiode

On/Off sensor push buttons / Relays /


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Sensors:

sensors are used in a wide range of control systems that makes lives forpeople

easier,

safer and

more productive both at work and at home.

Sensors extend the reach of human capabilities so that we can save energy,

make faster decisions

and perform tasks with greater precision.

Sensors take on highly repetitive tasks

leaving us free to apply our intellectual and creativeabilities to further improve our lives.

How we wash our clothes and refrigerate our food OR how we drive ourcars and generate energy sensors help us.
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Different types of sensors


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Common usage of sensors:

Transport and case Refrigeration Systems:

Temperature sensors are used to measure the supply of air to

temperature controlled compartments while immersion probes

measure refrigerant temperature. Rugged sensors designed

specifically for measuring refrigerant pressure are used in

conjunction with variable speed compressors to improve system

efficiency.

Traffic /smart Highway

Piezoelectric axle detectors are used to collect traffic data on highways,classify vehicles for automated toll booths, as well as provide timing

mechanism for speed and red light cameras.
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Petrol Pump

A rugged, hermetically sealed electromagnetic rotary

encoder coupled to the fuel flow meter in gas pumps is

used to accurately convert rotational pulses into gallonsor liters dispensed.

Printers : The drying process of ink jet printers isimproved by monitoring air and paper humidity content.

Measuring air and toner humidity guarantees print quality

in laser printers/copiers.
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Cooking System:

Long life, high-temperature oven probes operate up to

300C. The high accuracy optimizes cooking control

while protecting users.

Washer/Dryer:

Low cost/low power vibration sensors measure load

imbalance to avoid "walking." Humidity or thermopile

sensors are used in dryers to automatically shut off whenclothes are dry, extending the life of clothes and

improving efficiency.


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Working

If a current transformer has primary to secondary current

ratio of 100:5then it step up the voltage 20times and

step down the current 1/20times of its actual value.

If we know the current ratio I1/I2and the reading ofa.c.ammeter, the current can be calculated.

Current = ratio ammeter reading


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Potential transformer

A PT is a step down transformer having many primaryturns but few secondary turns.

In step down the voltage decreases and current

increases, thus voltage can be easily measured by usinglow range voltmeter.

The voltage is stepped down in known ratio called

voltage ratio.


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Construction and working of P.T.

Construction A potential transformer has many primary windings but

few number of secondary windings that makes it step

down transformer.

Voltmeter is connected to secondary winding usually

voltmeter of 150 v is suitable.

Working

Primary terminals are connected across the line to which

the voltage is to be measured.

The voltmeter gives the transformed value of voltage at

secondary.

The deflection of voltmeter when divided by transformedratio gives the actual voltage at primary.

Line voltage = deflection / trasf. RatioWhere transformation ratio = V2/V1


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Types of P.T.

Some types of p.t. are

1. Shell type

2. Dry type

3. Oil type

Rating Type

below 5000 v Shell type

5000-13800 v Dry type and

oil type

above 13800 v only oil type


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Automation and electricity demand

In the near future, home automation systems may be linked to theelectricity utility in a number of ways. The utility may communicatevariations in electricity prices to a smart electricity meter, that willinterface with the home automation controller.

Householders can then program appliances to reduce power or

switch off altogether during high price periods.

Alternatively householders could enter a supply contract that allowsthe electricity supplier to signal equipment controlled by the homeautomation system (such as air conditioners) to turn off certainequipment for short periods.

The householder may choose to participate and obtain lowerelectricity prices or other financial incentives.


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Desirable Sensor attributes

Reliability

Accuracy and Repeatability

Good response time.

Withstanding capability.

Long Life

Less expensive

R t bilit d


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Repeatability and accuracy

Not repeatable

Not accurateNot repeatable

Accurate

Repeatable

Not accurate

Repeatable

Accurate


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What is difference between sensor and a

transducer?

SENSOR and TRANSDUCER both are actually

sensors, but:

TRANSDUCER: convert one form of energy intoELECTRICAL energy

SENSOR: convert one form of energy into any other form

of energy


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Commonly used sensors for industrial

applications

Information from the sensor

/ Transducer can be in

two forms

Analog

Digital

LVDT

Pressure Transducer

Strain Gauge sensor

Magnetic sensors Piezoelectric sensors

Photoelectric sensors

Limit switches

Relays (Relay contacts Auxiliary contacts of

switch/ contactor /breaker


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In analog technology, a wave is recorded or used in its original form. So, for

example, in an analog tape recorder, a signal is taken straight from the

microphoneand laid onto tape. The wave from the microphone is an analog

wave, and therefore the wave on the tape is analog as well. That wave on the

tape can be read, amplified and sent to a speakerto produce the sound.

In digital technology, the analog wave is sampledat some interval, and then

turned into numbersthat are stored in the digital device. On a CD, the

sampling rate is 44,000 samples per second. So on a CD, there are 44,000

numbers stored per second of music. To hear the music, the numbers are

turned into a voltage wavethat approximates the original wave.The two big advantages of digital technology are:
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SENSORS used in the Industry

Thermocouples

Proximity sensors

Limit switches

RPM sensor

4-20 mA Transducers (current

voltage,frequency,KW,KVA,KVAR,PF,Phase

angle)


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Sensors

ControllersActuatorsHMI

Display & alarm

Basic Elements of Automation


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What is a controller ?

A controlleris a device whichmonitors and affects theoperational conditions of a givensystem.

A controller is a transfer elementwhich compares the feedbackvalue received from a transducer(sensor) to a predetermined value(i.e. set-point) and processes it insuch a way that a control signal istransmitted in the form of anappropriate variable to the

actuating element .

Anything which is controllablemust be measurable andcomparable

Comparator compares a givenvalue with a set value

The simplest controller is acomparator.


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What is a controller ?

A device which accepts theinputs , measure them anddepending on thepredetermined conditionsactuate one or more devicesis called the controller.

Input signal which representscertain physical quantity canbe digital or analog in thenature

An information from the sensor

is to be converted into

electrical form by signal

conditioners and amplifiers

before it is processed by the

controller If the information is analog

then a suitable ADC is used to

enable controller read

information

P bl A t ti


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Programmable Automation

Controller

A programmable automation controller(PAC)is a compactcontroller that combines the features and capabilities of a PC-based control systemwith that of a typical programmable logiccontroller(PLC). PACs are most often used in industrial settingsfor process control, data acquisition, remote equipment

monitoring, machine vision, and motion control. Additionally,because they function PACs are able to transfer data from themachines they control to other machines and components in anetworked control system or to application softwareand databases.

[edit]PAC Origins
http://en.wikipedia.org/wiki/Control_systemhttp://en.wikipedia.org/wiki/Programmable_logic_controllerhttp://en.wikipedia.org/wiki/Programmable_logic_controllerhttp://en.wikipedia.org/wiki/Process_controlhttp://en.wikipedia.org/wiki/Data_acquisitionhttp://en.wikipedia.org/wiki/Machine_visionhttp://en.wikipedia.org/wiki/Motion_controlhttp://en.wikipedia.org/wiki/Application_softwarehttp://en.wikipedia.org/wiki/Databaseshttp://en.wikipedia.org/w/index.php?title=Programmable_automation_controller&action=edit&section=1http://en.wikipedia.org/w/index.php?title=Programmable_automation_controller&action=edit&section=1http://en.wikipedia.org/wiki/Databaseshttp://en.wikipedia.org/wiki/Application_softwarehttp://en.wikipedia.org/wiki/Motion_controlhttp://en.wikipedia.org/wiki/Machine_visionhttp://en.wikipedia.org/wiki/Data_acquisitionhttp://en.wikipedia.org/wiki/Process_controlhttp://en.wikipedia.org/wiki/Programmable_logic_controllerhttp://en.wikipedia.org/wiki/Programmable_logic_controllerhttp://en.wikipedia.org/wiki/Control_system


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Types of controllers

Controllers can be categorized based on

1 Parameter Or physical quantity they are controlling

Examples Temperature controller,RPM controller,

Pressure controller etc

2 The manner in which they are controlling the Physical quantity

Proportional controller PProportional Integral controller PI

Proportional Integral derivative Controller PID

ONOFF (Bang Bang) Controller

3 Analog or Digital controller

4 The device used for controlling { PLC , PC ( computer), Digital circuitsusing comparators }


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Controllers used for building automation can be

grouped in 3 categories.1. Programmable Logic Controllers (PLCs)

2. , System/Network controllers, and

3. Terminal Unit controllers.

PLCs provide the most responsiveness and processingpower, but at a unit cost typically 2 to 3 times that of aSystem/Network controller intended for BASapplications.

Terminal Unit controllers are usually the least expensiveand least powerful.
http://en.wikipedia.org/wiki/Programmable_Logic_Controller


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Controller

Controllers are essentially small, purpose-builtcomputers with input and output capabilities.

These controllers come in a range of sizes andcapabilities to control devices commonly found in

buildings, and to control sub-networks of controllers. Inputs allow a controller to read temperatures, humidity,

pressure, current flow, air flow, and other essentialfactors.

The outputs allow the controller to send command and

control signals to slave devices, and to other parts of thesystem.

Inputs and outputs can be either digital or analog

Mi P d


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MicroProcessor and

Microcontroller

Microprocessors are these days replaced by Microcontrollers


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Selection Criteria for Controller:

Speed

Memory

I/O handling capability

Communication capability Built in Features

in Built ADC

in built DAC


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Programming:

A controller chip without a S/Wloaded in it has little power tocontrol.

A controller understands onlyzeros and ones (in fact it doesn'teven understand zeros and onesit can only distinguish two levels

low and High The lowest level language is

Machine language which has onlytwo characters . The morse codeis perhaps the best example ofmachine language

Assembly level language depends onthe type of the controller eachcontrller will have a fixed numberof instruction set.

Highest level languages are thosein which human beingscommunicate..

There are many higher levellanguages depending on the typeof application for which they areused.

Examples are

FORTRAN

COBOL

BASIC

FOXPro

Compilers and Assemblers


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C

C++

Java


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Programming the controllers:

Controller withoutprogramming has no value

Programming Languages

Higher level LanguagesC,C++.Java,Visual Basic

Assembly languages

Controller specific

Machine language

Will have series of zerosand ones

(morse code is the best

example)


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Types of Instructions

I/O Handling

Assigning

Mathematical

Logical

Repetitive

Branching

A building Automation system (BAS)


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A building Automation system (BAS)


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Continuous and Discrete Systems:

II. Continuous

Continuous processes used inindustrial automationapplications produce verylarge quantities of product.

Examples

The control of the watertemperature in a heating

jacket, is an example ofcontinuous process control.

Some examples ofcontinuous processes arethe production of fuels,chemicals and plastics.

3 Discrete

Found in manufacturing,motion and packagingapplications.

Examples :

Robotic assembly,commonly found inautomotive production,can be characterized asdiscrete process control.

Most discrete

manufacturing involvesthe production of discretepieces of product, such asmetal stamping.

S per isor control & Data Acq isition


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Supervisory control & Data Acquisition

(SCADA)

SCADArefers to a system thatcollects data from various

sensors at a factory, plant or in

other remote locations and

then sends this data to a

central computer which thenmanages and controls the

data.

SCADAfocuses on gathering and

circulating the right amount ofsystem information to the right

person or computer within the

right amount of time.


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DCS and SCADA

DCS is a very broad term used in a variety of industries, to monitor andcontrol distributed equipment.

SCADA is an acronym for Supervisory Control And Data Acquisition.SCADA systems perform data collection and control at the supervisorylevel. Some systems labeled as SCADA perform data acquisition only.

A SCADA system should not be critical to the controlled process. TheSCADA connects to a PLC or real time device, so there is a separate orintegrated real-time automated control system that responds quickly enoughto compensate for process changes within the time constants of theprocess.

The SCADA controls and monitors the process, but the process must alsorun independently from the SCADA system in case of failure.


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Role of communication in Automation:

Communication has played avital role in the process of

Automation

The controller receives the

inputs from various sensorsand also receives the inputsfrom the communication bus.

Master control is usually atcentralized location and in itmust receive data from all thelocations to enable it to toprocess the inputs and reachto the decision

Different protocols are used totransfer the data to thecontroller


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Sensors

Controllers

Actuators

HMIDisplay & alarm

Basic Elements of Automation

What is an actuator ?


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What is an actuator ?Definition for actuator:

a mechanism that puts

somethinginto automatic action .

An actuatoris amechanical device formoving or controlling a

mechanism or system. An actuator is operated

by a source of energy,usually in the form of anelectric current, hydraulic

fluid pressure orPneumatic pressure , andconverts that energy intosome kind of motion.

Different actuators used to control thegiven system

Relay

Solenoid Valve

Motor

MHT

Contactor

In addition to above types ofactuators a system can becontrolled by a digital signal (flag)generated locally or receivedfrom remote end device throughcommunication channel using a

certain protocol for thecommunication

Actuators


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Actuators

Actuators can be

categorized based on1. Energy source used electrically operated

Pneumatically operated

Hydraulically operated

Gas operated

2. Type of Motion

Linear motion

Rotary motion

Oscillatory motion

Perhaps the most commontype of actuator is powered byair the pneumatic cylinder,also known as the air cylinder

. Air cylinders are air-tightcylinders, typically made frommetal, that use the stored

energy of compressed air tomove a piston when the air isreleased or uncompressed.They are most commonly usedin manufacturing andassembly processes.

Grippers, which are used inrobotics, use actuators that aredriven by compressed airtowork much like human finger
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RELAY:

Relay is an electromechanical device and has apredesigned operating voltage.

Essentially it has a coil,a plunger,a spring and atleastone pair of sands operations coil gets energized andelectromagnetic action as aresult of current flow in the

coil attracts the plunger resulting in the change ofcontact position.

Contacts are designed to carry large current comparedto the operating current of the coil.Contact material canwithsatnd several thousands operations

The relays are available in different types(sealed,Unsealed) latching /non latching and ac/dcoperating voltages, The contacts available in the relaysare N/O .N/c or C/O types.


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Relay and Contactor:

Contactor again works on the same principle howevercontactor has two types of contacts .Main contacts

and auxiliary contacts. Auxiliary contacts are used to

give the status to the controller while main contacts carry

the controlled current. Contactors are available in different sizes depending on

the current carrying capability of the main contacts


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Solenoid:

A solenoid also operates on the principle of electromagnetism likerelay however in addition to changing the status of the contacts

solenoid plunger movement also initiates mechanical movement

leading to change in the positions of other mechanical components

to control the pnematic Hydraulic or electrical circuits.


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Stepper Motors Used for measured

rotationCan be held at a

particular position of

the shaftIdeal for many

autonomous robotsrequiring higher

precision


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Servo Motors :Used in closed loop control

systems in which work isthe control variable.

An integral feedbackdevice (resolver) ordevices (encoder andtachometer) are eitherincorporated within theservo motor or areremotely mounted, often

on the load itself


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Double acting actuator

A double acting actuatoris a mechanical device designed to supply powered bi-directional actuation for secondary mechanisms. This is in contrast to single action orspring return actuators and solenoids, which feature a powered stroke in onedirection only and rely on a secondary source of energy to reset or return theactuator. The double acting actuator is typically driven by electric motors orcompressed oil and gas. Electrically-driven double action actuators supply their bi-directional force by means of a motor reversing control circuit. Compressed gas andoil actuators feature opposed inlet valves that direct the motive agent to one side or

the other of the actuator mechanism. Actuators are devices used to operate a machine or mechanism remotely bysupplying a predetermined range of powered output movement. This movement isgenerally broken down into two strokes in opposed directions. These may beactivation and recovery strokes or bi-directional operating strokes. Activation andrecovery systems are well-illustrated by a metal stamping machine where the die ispushed down for the activation stroke and recovered, or returned, to a neutralposition in readiness for the next cycle. A bi-direction output may be seen in

a valveactuator, which turns in one direction to open the valve and in the oppositedirection to close it.

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Summary Automation has a wide spread presence in almost every industry and
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Automation has a wide spread presence in almost every industry andhomes

Automation systems consist of sensors controllers and an actuators.

There are variety of sensors depending on the physical quantity to be

controlled. In power system the most common sensors are CTs and PTs The simplest type of controller is a comparator and the advanced controllersare programmable and are capable of handling number of inputs andoutputs. Microcontrollers and computers are widely used these days in theautomation.

Controllers must be programmed for the given sets of Inputs and outputs toget the desirable results. All the intelligence is embedded in the controller

after programming in higher level languages and using suitable compilers. There are different types of actuators controlling linear and rotational motion

and the most common actuators are Solenoids ,Relays and Motors

Communication plays a very important role in the Automation system anddepending on the application a particular Protocol is used. Internettechnology has revolutionized the automation. In Substation Automation61850 protocol is used for acquiring data .

Automation has many advantages including making our lives comfortableand enable human beings to do the things which otherwise would havebeen impossible to do manually with same efficiency and accuracy.

Automation changes the nature of jobs and demands new skills and it is amyth that it leads to unemploymentIt has shifted the focus fromManufacturing industries to the Service related industries

industrial automation 4

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