PLC Circuit Design And Basic Programming By Manish kumar
1. PLC Circuit Design And
Basic Programming
at BOSCH Lmt., Jaipur
Manish Kumar
11EBKEX028
2. Contents covered in the Training
Basic circuits used in industry
Basic of PLC
Ladder logic programming
PLC circuit designs
Project
Spherical bolt greasing machine
Electrical drawing of machine
PLC programming of machine
4. Introduction
A Programmable Logic Controller (PLC) is an industrial
computer that accepts inputs from switches and sensors,
evaluates these in accordance with a stored program, and
generates outputs to control machines and processes.
PB1
LS1
INPUTS
M1
M2R
LOGIC OUTPUTS
M1
SOL
Block Diagram of a Control System
5. Major Components of a Common PLC
PROCESSOR
POWER
SUPPLY
I M
N O
P D
U U
T L
E
O M
U O
T D
P U
U L
T E
PROGRAMMING
DEVICE
From
SENSORS
Pushbuttons,
contacts,
limit switches,
etc.
To
OUTPUT
Solenoids,
contactors,
alarms
etc.
6. Major Components of a Common PLC
POWER SUPPLY
Provides the voltage needed to run the primary PLC components
I/O MODULES
Provides signal conversion and isolation between the internal logic-level signals inside
the PLC and the field’s high level signal.
PROCESSOR
Provides intelligence to command and govern the activities of the entire PLC systems.
PROGRAMMING DEVICE
used to enter the desired program that will determine the sequence of operation and
control of process equipment or driven machine.
7. What' happens in an operating cycle
Based on the data in
the output image file
the PLC energises or
de-energises it’s output
circuits,controlling
external devices.
1.Input
Scan
2. Program
Scan
3. Output
Scan
START
-
- -
-
PLC
OPERATING
CYCLE
TYPICALLY
1 to 25 ms.
During the input scan PLC
examines the external input
devices -On or Off.
The status of the inputs is
temporarily stored in an input
image memory file.
The PLC scans the instructions in the ladder
logic program,uses the input status from the
input image file & determines if an output will
be energised.The resulting status of the outputs
is written to the output image memory file.
8. Inputs and outputs of PLC
INPUTS
Pushbuttons
Selector Switches
Limit Switches
Level/Pressure/Temperature
Sensors
Photoelectric Sensors
Motor Starter Contacts
Relay Contacts
Transducers/Transmitters
Encoder
OUTPUTS
Relay
Motor Starters
Solenoids Valves
Control Relays
Alarms
Lights
Fans
9. Programming in PLC
Ladder Logic
Structured Text
Sequential functional chart
Functional Block Diagram
Instruction List
10. Programming in PLC
Ladder Logic
Structured Text
Sequential functional chart
Functional Block Diagram
Instruction List
11. Ladder logic
Ladder Logic is a graphical system of symbols and terms.
Those who are not familiar with relay wiring. Diagram, can easily learn it.
In ladder logic, we have to translate all of the items we're using into symbols
the PLC understands
13. The various components used in the panel are as
follows PLC
SMPS
PLC S7-200
Connectors
Wires
Main switch
Selector switch
Push buttons
Emergency switch
Relay
Sensors
Outside view of the panel
14. Spherical Bolt greasing Machine
A spherical bolt greasing machine
is made to reduce the
manufacturing cost of spherical
bolt. Previously what is happing the
spherical bolt was manufactutered
in the BOSCH ,but it is sent to
Bangalore for harding of the
component by doing the cadmium
and magnesium coating on it. This
increasing the cost of the
component. The BOSCH, Jaipur
researched that the lubricating the
component ,it can be used in the
assemblyeasily and it is reducing
the cost of the component and this
machine is made for this purpose.
In this machine the PLC circuit
Desgin panel is used.
Spherical bolt greasing machine
15. ELECTICAL DRAWING OF MACHINE
Power Diagram
Main switch from power
supply
SMPS is switch mode power
supply
MCB is miniature circuit
breaker
5.2.1POWER DIAGRAM
Power diagram of the spherical bolt greasing machine
16. PLC Inputs
I1 is the start no switch
I2 is the stop nc switch
I3 is NC auto switch
I4 is NC emergency push button
switch
I5 read switch of cylinder back
I6 is read switch of cylinder forward
I7 is flow sensor for lubrication is
coming or not
I8 is the proximity sensor at compent
is at loading
I9 is proximity sensor at the
component at lubrication point
17. PLC OUTPUT DIAGRAM
R1,R2,R3 arerealy coil connected at the
PLC output
CONTROL DIAGRAM
K1 is the connector supply of vibrator
K2 is the connector supply of the lubrication
unit motor
Valve is the supply of the solinoide vavle of
cylinder
Output of PLC
Control circuit of spherical bolt machine
19. Inputs and Outputs
Inputs Description
I0.0 START NO PUSH BUTTON
I0.1 STOP NC PUSH BUTTON
I0.2 AUTO SLECTOR NC SWITCH
I0.3 EMERGENCY NC SWITCH
I0.4 NO READ SWITCH OF CLYINDER BACKWARD
I0.5 READ SWITCH OF CLYINDER FORWARD
I0.6 NO FLOW SENSOR
I0.7 NC SENSOR AT COMPONENT AT LOADING CLYINDER
I1.1 NC SENSOR AT LUBRICATION POINT OUT
Output Description
Q0.0 VIBRICATOR
Q0.1 LUCRICATION MOTOR
Q0.2 PNEUMATIC CYLINDERS
Memory bit Description
M0.1 CLYINDER SET
M15.0 START AUTO SET
M15.1 SET START
M15.2 SET EMERGENCY
SM0.0 CALL SUBROUTINE BIT
20. Ladder logic program of machine
Ladder logic of main program
Inputs Description
I0.0 START NO PUSH BUTTON
I0.1 STOP NC PUSH BUTTON
I0.2 AUTO SLECTOR NC SWITCH
I0.3 EMERGENCY NC SWITCH
I0.4 NO READ SWITCH OF CLYINDER BACKWARD
I0.5 READ SWITCH OF CLYINDER FORWARD
I0.6 NO FLOW SENSOR
I0.7 NC SENSOR AT COMPONENT AT LOADING CLYINDER
I1.1 NC SENSOR AT LUBRICATION POINT OUT
21. (a)Ladder logic of auto program
Inputs Description
I0.0 START NO PUSH BUTTON
I0.1 STOP NC PUSH BUTTON
I0.2 AUTO SLECTOR NC SWITCH
I0.3 EMERGENCY NC SWITCH
I0.4 NO READ SWITCH OF CLYINDER BACKWARD
I0.5 READ SWITCH OF CLYINDER FORWARD
I0.6 NO FLOW SENSOR
I0.7 NC SENSOR AT COMPONENT AT LOADING CLYINDER
I1.1 NC SENSOR AT LUBRICATION POINT OUT
22. (b) Ladder logic of auto program
Inputs Description
I0.0 START NO PUSH BUTTON
I0.1 STOP NC PUSH BUTTON
I0.2 AUTO SLECTOR NC SWITCH
I0.3 EMERGENCY NC SWITCH
I0.4 NO READ SWITCH OF CLYINDER BACKWARD
I0.5 READ SWITCH OF CLYINDER FORWARD
I0.6 NO FLOW SENSOR
I0.7 NC SENSOR AT COMPONENT AT LOADING CLYINDER
I1.1 NC SENSOR AT LUBRICATION POINT OUT
23. Conclusion
The technical internship program was aimed at providing a practical
experience and exposure. It was directed towards enhancing the knowledge
about the upcoming technologies and how they are actually used.
The basic role was understanding the Automation. It is the use of control
systems such as PLC, SCADA,HMI, etc. to control industrial machinery and
processes, replacing human operators which greatly reduces the need for
human sensory and mental requirements.
I made a logic for a machine named SPERICAL BOLT GREASING MACHINE in
PLC which aims to achieve automation of a lubrication of the spherical bolt
one of the component of VE pump which is the main product manufactured
at BOSCH.
