PLC Programming Example on Timers Function Block

In this article, you will learn the PLC programming example on timers function block using switch and lamps.

Last updated: April 5, 2024 7:41 am

4 Min Read

In this article, you will learn the PLC programming example on timers function block using switch and lamps.

Contents

Note: The PLC example logic presented is for educational resource for engineering students and technicians to learn the basics.

PLC Programming Example on Timers

Problem Statement

Design a PLC ladder logic for the following application.

We are using one toggle switch to control two lamps.

When Switch 1 is ON, then

Lamp 1 will be ON for 10 seconds.
Lamp 2 will be ON after 10 seconds.

PLC Mastery Video

Watch the below video to master the PLC programming for beginners.

PLC Ladder Logic Example - Timers Example

I/O List

Digital Inputs:

The list of digital inputs shown below.

Switch 1: I0.0

Digital Outputs:

The list of digital outputs shown below.

Lamp 1: Q0.0

Lamp 2: Q0.1

Ladder Logic

PLC Programming Example on Timers Function Block

PLC Program Description

Here we used Normally Open Contact for Switch 1 (I0.0).

Timer Function Block Type TP is used for Lamp 1 and Time Function Block Type TON is used for Lamp 2.

In Rung 0:

1) Normally Open Contact is used for Switch 1 to Turn ON Lamp 1.

2) Timer Function Block type TP is used to Turn OFF Lamp 1 after Set time.

In Rung 1:

1) Normally Open Contact is used for Switch 1 to Turn ON Lamp 2.

2) Timer Function Block type TON is used to delay the time of Lamp 2 to Turn ON.

When Switch 1 is ON, the signal will flow through Switch 1 as Normally Open Contact is used for Switch 1 and Lamp 1 will Turn ON for 10 seconds because Timer Function Block type TP is used for Lamp1 and time is set for 10 sec.

After 10 seconds, Lamp 2 will Turn ON in Rung1 as Timer Function Block type TON is used for Lamp 2 to delay the turning ON and time is set for 10 sec.

Simulation Results

Here we show the PLC logic simulation results.

When Switch 1 is ON

When Switch 1 is turned ON, Lamp 1 will Turn ON for 10s in Rung 0 as Timer Function Block Type TP is used for Lamp 1.

After 10 seconds, Lamp 1 will Turn OFF and Lamp 2 will Turn ON in Rung 1 because Timer Function Block Type TON is used for Lamp 2 which will delay the time of Lamp 2 to Turn ON for Set time.