Question 2

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


  • Switch S1 and Switch S2 ON —– motor 1 ON
  • Switch S3 or Switch S4 ON —— lamp 1 ON & motor 1 OFF
  • Switch S5 ON —– lamp 1 OFF & motor 1 ON again

When S1 and S2 ON (Both are in ON Condition) it 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).

Solution: Ladder Logic & Explanation