What is the main component responsible for executing the user program in a PLC?
A
Input Module B
Power Supply C
Central Processing Unit (CPU) D
Output Module
Analysis & Theory
The CPU handles processing of all instructions and logic.
Which part of a PLC receives signals from sensors like push buttons or limit switches?
A
CPU B
Input Module C
Output Module D
Memory
Analysis & Theory
The input module takes field signals and converts them for processing.
What is the role of ROM in a PLC system?
A
Temporary storage of sensor data B
Storage of power supply status C
Permanent storage of the user program D
Execution of timer instructions
Analysis & Theory
ROM stores the program so it is not lost during power failure.
Which instruction is used to count upward in a PLC program?
A
TON B
CTU C
JMP D
MOV
Analysis & Theory
CTU (Count Up) increases the counter value when triggered.
Which instruction is used to delay output after a condition becomes true?
A
CMP B
TOF C
TON D
ADD
Analysis & Theory
TON (Timer ON Delay) waits before activating the output.
Which of the following is an arithmetic instruction in PLCs?
A
CMP B
ADD C
CTD D
RET
Analysis & Theory
ADD is used for arithmetic addition.
What is a common application of a PLC in industry?
A
Word processing B
Mobile game development C
Motor and conveyor control D
Web page design
Analysis & Theory
PLCs are used to automate processes like motor and conveyor operations.
What type of signal does an output module send?
A
Field signal to CPU B
Sensor data to memory C
CPU command to actuators D
Power supply status
Analysis & Theory
The output module sends control signals to actuators and other devices.
Which instruction moves data from one register to another?
A
MOV B
TON C
AND D
CTU
Analysis & Theory
MOV is used to transfer data from one location to another.
What does CTD stand for in PLC programming?
A
Counter Down B
Control Terminal Device C
Current Time Display D
Cycle Time Delay
Analysis & Theory
CTD is a down counter used to count decreasing events.