PLC Circuit Design And Basic Programmingat BOSCH Lmt., Jaipur

Manish Kumar

11EBKEX028

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

Content

Introduction of PLC Programming in PLC(Ladder logic) PLC circuit design Project

Spherical bolt greasing Machine

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

INPUTSM1

M2R

LOGIC OUTPUTS

M1

SOL

Block Diagram of a Control System

Major Components of a Common PLC

PROCESSOR

POWERSUPPLY

I MN O P D U UT L E

O M U OT DP UU LT E

PROGRAMMING DEVICE

From SENSORS

Pushbuttons,contacts,

limit switches,etc.

ToOUTPUT

Solenoids, contactors,

alarmsetc.

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.

What' happens in an operating cycle

Based on the data inthe output image filethe PLC energises or de-energises it’s outputcircuits,controllingexternal devices.

1.Input Scan

2. ProgramScan

3. OutputScan

START

-- -

-

PLCOPERATING CYCLETYPICALLY 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 willbe energised.The resulting status of the outputsis written to the output image memory file.

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

Programming in PLC

Ladder Logic

Structured Text

Sequential functional chart

Functional Block Diagram

Instruction List

Programming in PLC

Ladder Logic

Structured Text

Sequential functional chart

Functional Block Diagram

Instruction List

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

PLC CIRCUIT DESGIN

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

SensorsOutside view of the panel

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

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

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

PLC OUTPUT DIAGRAM R1,R2,R3 arerealy coil connected at the

PLC output

CONTROL DIAGRAMK1 is the connector supply of vibrator K2 is the connector supply of the lubrication unit motorValve is the supply of the solinoide vavle of cylinder

Output of PLC

Control circuit of spherical bolt machine

FLOW CHART OF MACHINE WORKING

Flow chart of machine

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

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

(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

(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

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.

References

SIMATIC S7-200 CPUs

http://w3.siemens.com/mcms/programmable-logic-controller/en/simatic-s7-controller/s7-200/cpu/Pages/Default.aspx

http://www.wikipedia.com/

http://w3.siemens.com/mcms/simatic-controller-software/en/step7/step7-micro-win/Pages/Default.aspx

http://www.google.com/

Thank You