Basic PLC Ladder Programming Training Example 15 : Automatic Door Open Close System PLC Ladder Program
Basic PLC Ladder Programming Training Examples for Beginners. Hi Friends here we are starting a series of Free Training on PLC Ladder Programming. These PLC Ladder Programs are important to get basics of Ladder Programs
PLC Ladder Practice Problem:
- When someone enters the infrared sensing field, opening motor starts working to open the door automatically till the door touches the opening limit switch
- If the door touches the opening limit switch for 7 sec and nobody enters the sensing field, the closing motor starts working to close the door automatically till the closing limit switch touched together.
- Stop the closing action immediately if someone enters the sensing field during the door closing process.
PLC Ladder Programming:
|PLC Ladder Program for Automatic Door open Close|
PLC Ladder Programming Description:
- X0 = ON if someone enters the sensing field of the infrared sensor. Y0 will be ON and latched, and the door will be opened as long as the opening limit switches X2 = OFF.
- When the door touches the opening limit switches, X2 = ON. The timer T0 will start to count for 7 sec if no one enters the sensing field (X0 = OFF). After 7 sec., Y1 will be ON and latched and the door will be closed.
- During the closing process, X0 = ON if someone enters the sensing field. The NC contact X0 will be activated to turn Y1 off. Because X0 = ON, X2 = OFF and Y1 = OFF, Y0 will be ON and the door will be opened once again.