PLC engineer interview question?


PLC programmer / PLC engineer interview questions

  1. What is sinking input and sourcing input/Output ?

Sinking input / output provides a grounded connection to the load

Sourcing input / output provides to the load

2.What are the different types of modules used in plc?

Digital input
Digital Output
Analog input
Analog output
Pulse input
Communication module

3.What are the different types of plc programming languages?

Ladder logic, Functional Block Diagram , Statement list

4.What is scanning period ?

5.What is the meaning of “rung” ?

6.What is the meaning of Normally Opened contact

7.What is the meaning of normally closed contact?

8.What is relay ?

9.What is marshaling cabinet?

10.What is “Floating ground”?

11.What is system ground and safety ground ?

12.What are the different types of communication protocols used in PLC?

13.What is the full form of “PLC” ?

14.What is the meaning of scaling


ooh great work, this is so helpful for me. thank you