# Write Ladder Logic for the Simple Program

Write ladder logic for the simple ON/OFF of motor and lamp.

When

1. Switch S1 and Switch S2 ON —– Motor 1 ON
2. Switch S3 or Switch S4 ON —— Lamp 1 ON & Motor 1 OFF
3. Switch S5 ON —– Lamp 1 OFF & Motor 1 ON again

When S1 and S2 ON Both are In ON Condition) should make Motor 1 should go ON.

When S3 or S4 (Anyone ON) will make lamp 1 ON and Motor 1 (Which was already turned ON by S1) to go OFF.

When S5 ON, lamp 1 (Which was already turned ON by S3 or S4) should go OFF and Motor 1 again ON (Which was already turned OFF by S3 or S4).

## Logic Explanation

#### Network 1:

When switch 1 and switch 2 are pressed, the motor will turn on. Switch 3 and 4 are connected as normally closed contact in series with the output which will make output to go off when anyone goes ON.

Switch 5 is connected as normally open contact in parallel to turn ON motor again.

#### Network 2:

Switch 2 and 3 are connected as normally open contact in parallel with the output which will make output lamp 1 to go ON if anyone is ON.

Switch 5 is connected as normally closed contact to break the power line when switch 5 goes ON.

Author: Hema

Training Course: Siemens PLC Training

## Overview of Memory Section

The memory refers to the section of the PLC where data and instructions are stored (either temporarily or semi-permanently).

## Basic PLC Instructions

Symbolic representations of contacts and coils are the basic symbols of any ladder logic instructions set used in the PLC programming.

## PLC Ladder Logic for simple ON-OFF of Motor and Lamp

Design a simple PLC ladder logic to control the conveyor motor ON and OFF using switches and also indicate the status using lamps.

## PLC Program for Conveyor Motor

Write ladder logic for the simple ON-OFF of conveyor motor and lamp indication program using Allen Bradley PLC programming software.