Build the PLC programming ladder logic example program to turn ON/OFF the lamp using push buttons with respect to program logic conditions.

Problem Logic

1. Start PB and Stop PB are to turn ON and OFF the lamp.

2. After Start PB is pressed, in the following sequence, Outputs should turn ON/OFF

Q1 is turned ON for 5 seconds

Q2 is turned ON for 5 seconds

Q3 is turned ON for 5 seconds

Q4 is turned ON for 5 seconds

After 5 sec, Q4 has to off and the process should repeat until stop PB is pressed.

PLC Programming Logic

PLC Logic Description

Latching rung to operate the system through Master Start and Stop PB.

Latched M0 is connected with T0 which starts running. Normally closed contact of the T1 timer done bit is connected to make the process continue until stop PB is pressed.

Timer accumulator value is converted to binary.

Greater than or equal and Less than or equal block is connected in series with Q1, When accumulator value between 160(D100) to 200(D102) triggers Q1 turns ON. For Q2 the range is ( 110(D104) to 159(D106) ),for Q3 (50(D108) to 109(D110)) and for Q4 (0 (D112)to 49(D114))

Timer 1 will turn on after 5 sec of Q4, will turn off Q4, and repeat the cycle.

Note: This PLC example is from the Omron PLC course.

Author: Hema