ppt on PLC automation

Seminar on
(Programmable LogicController)
Presented By
Md Talib Khan
B.Tech (EEE) IVyr
HCE,BBSR

 What is PLC?
 History of PLC
 Major components of PLC
 PLC Operation
 PLC Programming & Examples
 PLC Configuration
 Programming Softwares
 Leading Brands of PLC
 Areas of Application
 Advantages
 Disadvantages
 Conclusion

 Programmable Logic Controller (PLC) is an industrial computer that
monitors inputs, makes decisions based on its program and controls outputs
to automate a process or machine.
 The automation of many different processes, such as controlling
machines or factory assembly lines, is done through the use of small
computers called a programmable logic controllers (PLCs)..

 PLC was introduced in late 1960’s
 First commercial & successful PLC was designed and developed by
MODICON.
Dick Morley was considered the ‘Father’ of Programmable Logic
Controller (PLC).
Earlier, it was a machine with thousands of electronic parts.
 Later ,in late 1970’s,the microprocessor became reality & greatly
enhanced the role of plc permitting it to evolve form simply relay to
the sophisticated system as it is today.

POWER
SUPPLY
Pushbuttons,
contacts,
limit switches,
etc.
From
SENSORS
To
OUTPUT
Indicators,
contactors,
alarms
etc.PROGRAMMING
DEVICE
I M
N O
P D
U U
T L
E
O M
U O
T D
P U
U L
T E
PROCESSOR

1. POWER SUPPLY
The power supply provides power for the PLC system.
Common power levels used are 24V DC or 120 VAC.
2. CENTRAL PROCESSING UNIT(CPU)
It is the brain of PLC and governs the activities of the entire PLC systems
 The CPU consists of following blocks :
Arithmetic Logic Unit (ALU),
Internal memory of CPU
Internal timers ,counters and Flags .
 The various operations performed are :
Scanning I/O bus traffic control,
Program execution,
Peripheral and External device communication,
Data handling and self diagnostics.
POWER
SUPPLY
PROCESSOR

3. INPUT MODULES that carry signals from the process into the controller.
Ex. : Switches, Pushbuttons, Sensors
4. OUTPUT MODULES that convert control instructions a signal that can be
used by actuators.
Ex. : Indicator Lamp, Motor
5. PROGRAMMING DEVICE
The programming terminal is
used for programming the PLC
and monitoring/sequencing PLCs
operation.

INPUTS OUTPUTS
PLC
Selector
switch
Proximity
Sensor
Limit
Switch
STOP
Pushbutton
START
Pushbutton
Indicator
Light
Contactor
Motor
Relay

 CHECK INPUT STATUS
First the PLC takes a look at each
I/O to determine if it is on or off.
 EXECUTE PROGRAM
Next the PLC executes the
program
one instruction at a time.
 UPDATE OUTPUT STATUS
Finally the PLC updates the status
of the outputs .It updates the outputs
based on which inputs were on
during the first step.

NORMALLY
OPEN
NORMALLY
CLOSED
COILS
ELEMENTS OF LADDER LOGIC
Ladder Logic
The ladder logic is the oldest programming
language for PLC.
 It is well suited to express Combinational
logic.
The main ladder logic symbols represent the
elements :
Ladder Logic Program for Start/Stop of
Motor :
X1
Y1
Y1X2
START STOP
COIL
COIL
(MOTOR)

LAD PROGRAM FOR STARTING A MOTOR AFTER A DELAY OF 5 SEC
FROM SWITCHING
MOTOR
START
PUSHBUTTON

Simatic S7
TIA Portal
Rockwell Software
Some Commonly Used Softwares in PLC Programming

Packaging
Robots
Manufacturing
Food Processing
Palletizing Material handling
Machine Control
Printing IndustryTextile Industry

Replacing Human Operators
Dangerous Environments
Beyond Human Capabilities
Flexibility in programming and reprogramming & have an easily
understood programming language.
Cost effective for controlling complex systems.
Improves Productivity
Small physical size, high speed of operation.
Ability to communicate with computer systems in the plant.
Ease of maintenance /troubleshooting.
Reduced space.
Energy saving.

Limited design and fixed Circuit Operations.
PLCs manufacturers offer only closed architectures.
PLC Devices Are Proprietary.
Initial Costs Are High.
Unemployment Rate Increases.

 The PLC 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 a small number of relays to complex automation problems.
 Today the PLCs are used for control & automation job in a single
machine & it increases up to full automation of manufacturing / testing
process in a factory.

 “www.plcs.net/” : Containing PLC References, Providing Video
tutorials, and also offering PLC related jobs
“https://en.wikipedia.org/wiki/Programmable_logic_controller”
: Providing all details about PLC.
 “www.realpars.com/” : Having tutorial videos for Learning
PLC.

ppt on PLC automation

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ppt on PLC automation