Which part of a modular PLC is responsible for processing instructions?

The part of a modular PLC (Programmable Logic Controller) that is responsible for processing instructions is the CPU, or Central Processing Unit. The CPU acts as the brain of the PLC, executing the control program and performing arithmetic and logical operations as needed. It interprets the input data received from the input module, processes that information according to the programmed logic, and then sends commands to the output module based on the results of the processing.

In the context of a PLC, the input module collects data from various sensors and devices, converting this data into a format that can be understood by the CPU. The power supply is essential for supplying power to the entire PLC system but does not participate in instruction processing. The output module interfaces with actuators and other devices to implement the outputs as determined by the CPU, but it does not process instructions itself. Thus, the CPU is the central component responsible for making logical decisions and controlling the operation of the system based on the instructions programmed into it.