Unit 1 Introduction To Automation System-Books Download

UNIT 1 INTRODUCTION TO AUTOMATION SYSTEM

2019 | 3 views | 44 Pages | 1.99 MB

UNIT 1 : INTRODUCTION TO AUTOMATION SYSTEM General Objectives 1. Understand and learn about automation control systems and types of automation control systems. 2. Learn about the types of control system pneumatic control systems, hydraulic control systems and electrical control system. Specific Objectives; At the end of this chapter, student should be able to: 1. Define the Automation Control ...



INTRODUCTION TO AUTOMATION SYSTEM
The main objective of Automation Control System used in the industry are
1 to increase productivity
2 to improve quality of the product
3 Control production cost
1 1 1 Types Of Automation In The Industry
1 1 1 Classification of automation
a Permanent Fixed Automation
This control system is designed to perform a specific task
Functions of control circuit is fixed and permanent
It will be complicated if we want to do other task apart from the existing task
b Programmable Flexible Automation
Programmable automation or felxible automation is a complex control system that
can perform several tasks
Functions of control circuit programmed by the user and can be modified
When the task to be performed by machines changed changes only need to be done
by making modifications to the machine control program
1 1 2 Comparison Between Fixed And Flexible Automation System
FIXED FLEXIBLE
AUTOMATION AUTOMATION
Purpose Specific Variety
Ease of making changes upgrade
Difficult Easy
Maintenance Hard Easy
Depends on
Capability manufacturing and Very high
Speed Slow Fast
Suitable for small Suitable for
Economy efficiency
system all types of systems
SARIATI Page 2
INTRODUCTION TO AUTOMATION SYSTEM
Fixed Automation
S1 S2 lamp
Programmed Automation
0000 0000 1000
SARIATI Page 3
INTRODUCTION TO AUTOMATION SYSTEM
1 1 3 There Are Three 3 Types Of The Control System Based On Supply
a Pneumatic Control Systems
b Hydraulic Control System
c Electrical Control System
a Pneumatic Control System
Pneumatic control system is a system that uses compressed air to produce power
energy to perform any task
Pneumatic systems found in many industrial systems such as food industry
petrochemical and industrial involves robotics
Pneumatic systems requires
i Compressed air supply
ii Control valve
iii Connecting tube
iv Transducer
Pneumatic control system can be controlled manually and automatically
Basic Block Diagram of Pneumatic Control System using manual PLC
SARIATI Page 4
INTRODUCTION TO AUTOMATION SYSTEM
b Hydraulic Control System
Hydraulic control system is a system that uses fluid to generate power energy
The hydraulic system used in the automobile industry such as power systems braking systems
cranes car jack satellite and others
The fluid used is oil
The hydraulic system requires
a Hydraulic fluid supply
b Control Valve
c Cylinder
Hydraulic control system can be controlled manually and automatically
Basic block diagram of an automatic hydraulic control system by Manual PLC
c Electrical Control System
A control system that uses an electric current either direct current DC or current
shuttle AC as a source of supply
Electrical Control Systems Generally requires
a Electricity DC or AC
b Input elements switches sensors transducer valves electronic components
c Output elements motor lights etc
d Extension cable
SARIATI Page 5
INTRODUCTION TO AUTOMATION SYSTEM
Basic block diagram of a manual electric control system
Basic block diagrams of electrical control system using PLC
COMPARISON BETWEEN PNEUMATIC CONTROL SYSTEMS HYDRAULIC
CONTROL SYSTEM AND ELECTRIC CONTROL SYSTEM
i PNEUMATIC CONTROL SYSTEM
a Easy installation
b Simple design
c Use compressed air as a supply source to perform task
ii HYDRAULIC CONTROL SYSTEM
a Complex to assemble
b Use fluid like oil as a supply source to perform task
c Potential leakage will lead to pollution
iii ELECTRIC CONTROL SYSTEM
a Simple system
b Use electricity as a supply source to perform task
c Widely use either for home user or in industrial
SARIATI Page 6
INTRODUCTION TO AUTOMATION SYSTEM
1 1 4 Advantages And Disadvantages Of Automation Control In Industry
The main advantages of automation are
Replacing human operators in tasks that involve hard physical work
Replacing humans in tasks done in dangerous environments i e fire space volcanoes
nuclear facilities underwater etc
Performing tasks that are beyond human capabilities of size weight speed endurance
Economy 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
Reduces operation time and work handling time significantly
The main disadvantages of automation are
Unemployment rate increases due to machines replacing humans and putting those
humans out of their jobs
Technical Limitation Current technology is unable to automate all the desired tasks
Security Threats Vulnerability An automated system may have limited level of
intelligence hence it is most likely susceptible to commit error
Unpredictable development costs The research and development cost of automating a
process may exceed the cost saved by the automation itself
High initial cost The automation of a new product or plant requires a huge initial
investment in comparison with the unit cost of the product although the cost of
automation is spread in many product batches of things
TUTORIAL QUESTION
Give definition of Automation Control System 3m
Make a comparison between Fixed Automation and Flexible Automation Control
System 12m
State three 3 types of control system which based on supply source and states the
differences between them 12m
Sketch an automatic control system diagram for
a Hydraulic Control System
b Electric Control System
c Pneumatic Control System
SARIATI Page 7
INTRODUCTION TO AUTOMATION SYSTEM
1 2Explanation Of Relays And Contactors
The representation of relays and contactors in the electrical circuit diagram is identical as
their operating principle
i Relays are used to switch relatively small output and current
ii Contactor to switch relatively large output and currents
1 2 1 Relays
a Definition Relay
A relay is an electrically operated switch electromagnetically actuated switch Current
flowing through the coil of the relay creates a magnetic field which attracts a lever and
changes the switch contacts The coil current can be ON or OFF so relays have two switch
positions and most have double throw changeover switch contacts
b Types of Relays
Relays are usuallly SPDT Single Pole Double Throw or DPDT Double Pole Double
Throw but they can have many more sets of switch contacts
Poles the number of sets of contacts
Throw The number of positions or combinations open or close the contacts have
Several types of relays shown in the diagram below
Circuit symbol for a relay
SARIATI Page 8
INTRODUCTION TO AUTOMATION SYSTEM
The relay s switch connections are usually labelled COM NC and NO
COM Common always connect to this it is the moving part of the switch
NC Normally Closed COM is connected to this when the relay coil is off
NO Normally Open COM is connected to this when the relay coil is on
Connect to COM and NO if you want the switched circuit to be on when the relay coil
Connect to COM and NC if you want the switched circuit to be on when the relay coil
c Relay Building Diagram
The actual relay building diagram
A simple electromagnetic relay consists of a coil of wire wrapped around a soft iron
core an iron yoke which provides a low reluctance path for magnetic flux a movable iron
armature and one or more sets of contacts The armature is hinged to the yoke and
mechanically linked to one or more sets of moving contacts It is held in place by a spring so
that when the relay is de energized there is an air gap in the magnetic circuit
When an electric current is passed through the coil it generates a magnetic field that
activates the armature and the consequent movement of the movable contact s either
makes or breaks depending upon construction a connection with a fixed contact
If the set of contacts was closed when the relay was de energized then the movement
opens the contacts and breaks the connection and vice versa if the contacts were open
When the current to the coil is switched off the armature is returned by a force
approximately half as strong as the magnetic force to its relaxed position Usually this force is
provided by a spring but gravity is also used commonly in industrial motor starters Most
relays are manufactured to operate quickly In a low voltage application this reduces noise in
a high voltage or current application it reduces arcing
SARIATI Page 9
INTRODUCTION TO AUTOMATION SYSTEM
Relay Building Diagram
How Relays Work
1 When switch is ON press the current will flow through it
2 It will energize the electromagnet
3 Then the coil electromagnet will attract the lever
4 After the lever touch each other the electricity will flow to the load
Relay can be used for various regulating control and monitoring functions
i As interfaces between control circuits and load circuits
ii For signal multiplication
iii For separation of direct current and alternating current circuits
iv For delaying generating and converting signals and
v For linking information
SARIATI Page 10
INTRODUCTION TO AUTOMATION SYSTEM
d Example Of Relay Use In The Traffic Light System
Operating Principle
This circuit can be used to control traffic in public places or to demonstrate traffic
rules in traffic parks
IC2 which is heart of the circuit is a decade counter In this counter for every pulse
fed to pin 14 potential keeps shifting from D1 to D9 in cyclic order
IC1 is used as a pulse generator and generates pulses in regular configurable
intervals These intervals can be changed by varying VR1
The circuit is designed in such a way that out of nine pulses relay RL1 remains
triggered for 4 pulses relay RL2 for 1 pulse and relay RL3 for remaining 4 pulses
Since D1 D4 provide current to T1 T1 is on whenever there is potential on any diode
D1 to D4 which keeps relay RL1 triggered Similarly other diodes are responsible for
RL2 and RL3 triggering
Red Yellow and Green lamps can be connected to the relays RL1 RL2 and RL3
respectively to complete your mini traffic light controller
SARIATI Page 11
INTRODUCTION TO AUTOMATION SYSTEM
1 2 2 Contactors
d Definition Contactor
A relay that can handle the high power required higher current rating to directly
control an electric motor or other loads is called a contactor
A contactor is an electrically controlled switch used for switching a power circuit similar
to a relay except with higher current ratings
Contactors are used to control electric motors lighting heating capacitor banks and
other electrical loads
b Basic Component Of Contactor
A contactor has three components The contacts are the current carrying part of the
contactor This includes power contacts auxiliary contacts and contact springs The
electromagnet provides the driving force to close the contacts The enclosure is a frame
housing the contact and the electromagnet
Contactor building diagram
A basic contactor will have a coil input which may be driven by either an AC or DC
supply depending on the contactor design The coil may be energized at the same voltage as
the motor or may be separately controlled with a lower coil voltage better suited to control
by programmable controllers and lower voltage pilot devices
c Operating Principle
Unlike general purpose relays contactors are designed to be directly connected to
high current load devices Relays tend to be of lower capacity and are usually designed for
both normally closed and normally open applications Devices switching more than 15
amperes or in circuits rated more than a few kilowatts are usually called contactors Apart
from optional auxiliary low current contacts contactors are almost exclusively fitted with
SARIATI Page 12
INTRODUCTION TO AUTOMATION SYSTEM
normally open contacts Unlike relays contactors are designed with features to control and
suppress the arc produced when interrupting heavy motor currents
When current passes through the electromagnet a magnetic field is produced which
attracts the moving core of the contactor The electromagnet coil draws more current initially
until its inductance increases when the metal core enters the coil The moving contact is
propelled by the moving core the force developed by the electromagnet holds the moving
and fixed contacts together When the contactor coil is de energized gravity or a spring
returns the electromagnet core to its initial position and opens the contacts
i Main Contact
Main contact of the contactor are normaly open contact and usually use to connect power
load to the main supply
ii Auxiliary Contacts
Auxiliary contacts are secondary switching devices which work in conjunction with primary
switching equipment such as circuit breakers relays and contactors These contacts are
physically linked to the main switching mechanism and activate at the same time it does
Auxiliary contacts are commonly used as interlocks or retainers on the primary device s
control circuit and often used to give indication of its state of operation such as trip function
indication electrical interlocks and start circuit retainers Many contactors and circuit
breakers feature sets of auxiliary contacts as integral parts or they may be modular snap on
units which can be added or removed as required Auxiliary contacts are available with either
normally open or normally closed contact points or a combination of both
d Examples Application Of Contactor In Motor Control Sytem
1 DOL Motor Starter
2 A STAR DELTA Motor Starter
SARIATI Page 13
INTRODUCTION TO AUTOMATION SYSTEM
1 2 3 Difference Between Relay And Contactors
The Difference
1 Since a contactor is required for a higher load a relay is always cheaper than a
2 A relay is normally used in appliances below 5KW while a contactor is preferred
when the appliance is heavier
3 A relay is used only in control circuit while a contactor can be used in both control
and power circuits
4 In general contactors are little slower than relays
5 Contactor is so designed that it can be repaired while it is not normally done in the
case of relays
It should be noted that when installing contactors or relays that you always check the coil
ratings They often have not got a default rating of 230volts and only go bang once if they are
connected to the wrong voltage
SARIATI Page 14
Differences between Pneumatic
Hydraulic and Electrical control
Pneumatic Hydraulic Electric
1 Using Compress air as Using oil as supply source Using electricity as a
supply source supply source
2 Easy installation Complicated Installation Simple system
3 Simple design If leak will cause dirty Widespread use


Related Books

SOME OPEN PROBLEMS ON MULTIPLE ERGODIC AVERAGES

SOME OPEN PROBLEMS ON MULTIPLE ERGODIC AVERAGES

SOME OPEN PROBLEMS ON MULTIPLE ERGODIC AVERAGES NIKOS FRANTZIKINAKIS 1. Extended bibliography organized by topic Below we give a rather extensive bibliography with material that is directly related to the problems discussed before, organized by topic. We caution the reader that this is not a com-prehensive list of articles in ergodic Ramsey theory, and in fact articles on several important ...

Continue Reading...
Cambridge University Press 978-0-521-43800-1 - Conformal ...

Cambridge University Press 978-0-521-43800-1 - Conformal ...

310 Topics in dynamics and ergodic theory, S. BEZUGLYI & S. KOLYADA (eds) 311 Groups: topological, combinatorial and arithmetic aspects, T. W. M¨ULLER (ed) 312 Foundations of computational mathematics, Minneapolis 2002, F. CUCKER et al (eds) 313 Transcendental aspects of algebraic cycles, S. M¨ULLER-STACH & C. PETERS (eds)

Continue Reading...
Math 601D: Entropy in Information Theory, Ergodic Theory ...

Math 601D: Entropy in Information Theory, Ergodic Theory ...

[CT] T. Cover and J. Thomas, Elements of Information Theory, Wiley Press, 2nd edition, 2006. (an introduction to information theory) [K] G. Keller, Equilibrium States in Ergodic Theory, London Mathe-matical Society Student Notes, vol. 42, Cambridge U. Press, 1998 (a more advanced introduction to ergodic theory with emphasis on greater

Continue Reading...
Introduction to Dynamical Systems - QMUL Maths

Introduction to Dynamical Systems - QMUL Maths

measures. We conclude with a brief outline of essentials of ergodic theory. If you are interested in further pursuing these topics, please note that there is a strong research group at QMUL particularly focusing on (ergodic properties of) dynamical systems with crosslinks to statistical physics.2

Continue Reading...
Math 601D (Section 201): Entropy and Equilibrium States in ...

Math 601D (Section 201): Entropy and Equilibrium States in ...

[K] G. Keller, Equilibrium States in Ergodic Theory, London Mathe-matical Society Student Notes, vol. 42, Cambridge U. Press, 1998 (a more advanced introduction to ergodic theory with emphasis on greater generality and connections to ideas from statistical mechanics) [R] D. Ruelle, Thermodynamic Formalism, Cambridge Mathematical

Continue Reading...
School and Workshop on Dynamical Systems

School and Workshop on Dynamical Systems

(4) Ergodic theory and Diophantine problems, Topics in symbolic dynamics and applications (edited by F. Blanchard, A. Maass and A. Nogueira), London Math. Soc. Lecture Note Series 279 (2000), 167-205 (5) Minimal idempotents and ergodic Ramsey theory, Topics in Dy-namics and Ergodic Theory 8-39, London Math. Soc. Lecture

Continue Reading...
issue Number 30 Fall/WiNter 2011 TREK - alumni UBC 100

issue Number 30 Fall/WiNter 2011 TREK - alumni UBC 100

naturally fascinated with how their kids experience the world and their physical and psychological development, so they really enjoy watching them interact with researchers,” says Baron, who joined UBC’s Department of Psychology in 2010 from Harvard University, where he completed his PhD. the children interact with iPads, touchscreens,

Continue Reading...
1241c6-Study Guide For Nyc Food Handlers License

1241c6-Study Guide For Nyc Food Handlers License

Related eBook Available are : Choosing Outcomes And Accommodations For Children Coach A Guide To Educational Planning For Students With Disabilities Second Edition,Acct Financial Answers Tyler Godwin Alderman,Dyson Vacuum Cleaner Repair Manual,

Continue Reading...
K???SEL B?LG?LER

K???SEL B?LG?LER

Çekiç O., Öztürk H., "Evaluation of the Voucher Program in Turkey: Lower Income Families and Access to Private Education", Association for Public Policy Analysis and Management (APPAM) 2016 Spring Conference, Washington

Continue Reading...
06333d-Winchester Model 77 Repair Manual

06333d-Winchester Model 77 Repair Manual

Winchester Model 77 Repair Manual Ebook Pdf Winchester Model 77 Repair Manual contains important information and a detailed explanation about Ebook Pdf Winchester Model 77 Repair Manual, its contents of the package, names of things and what they do, setup,

Continue Reading...