Programmable Logic Controller - Creating Timer Application in PLC

The timers are key part of any programming logic. The post here describes how to set it up with a PLC IDe. These were the experiments and records i did as a student. Posting it here as a blog content.

Calling a Timer

Setting up a timer

The above example calls the timer T001 and programs time delay of 5 sec. Now with the above setting lets develop a Ladder Logic to implement a On-delay and a Off-delay timer.

Input – Output Allocation - On Delay Timer

Inputs:
	Switch – 0000
Output:
	LED – 0500.
Timer:
	T001

Ladder Logic Program - On Delay Timer

Ladder Logic Program - On Delay Timer

Input – Output Allocation - Off Delay Timer

Inputs:
	Switch – 0002
Output:
	LED – 0502.
Timer:
	T002

Ladder Logic Program - Off Delay Timer

Ladder Logic Program - Off Delay Timer

Lets Solve a Timer Problem

Lets perform an experiment to sequentially start Three Motors. The first Motor (M1) is started as soon as a Push Button is triggered. The Second Motor (M2) has to start 5 Secs after the M1. The third Motor (M3) will be started 10 Secs after the M2

Input – Output Allocation - 3 Motor Problem

<Relay>
<No.> <Label> <Comment1> <Comment2> <Comment3>
0000 :START Start Push Button
0500 :M1 Motor 1
0501 :M2 Motor 2
0502 :M3 Motor 3

<Timer>
<No.> <Label> <Comment1> <Comment2> <Comment3>
T000 :TMR1 Timer 1 - 5 Sec
T001 :TMR2 Timer 1 - 10 Sec

Ladder Program - 3 Motor Problem

Ladder Logic Program - 3 Motor Problem

Lets Generate a Pulse

Using two timers, write a program so we have a pulse on PLC output with (TON = 10 sec.) and (TOFF = 10 sec.)

Input-Output Allocation - Generating a Pulse

<Relay>
<No.> <Label> <Comment1> <Comment2> <Comment3>
0000 :S1 Start Switch
0001 :S2 Stop Switch
0500 :LED Output Led

<Timer>
<No.> <Label> <Comment1> <Comment2> <Comment3>
T000 :T1 5 Sec Off
T001 :T2 5 Sec On

Ladder Program - Generating a Pulse

Ladder Program - Generating Pulse