In PLC systems, which component typically handles the program execution?

In PLC (Programmable Logic Controller) systems, the component that handles program execution is the processor module. This module is responsible for interpreting the user-uploaded program, maintaining system control, and executing the instructions as they are defined in the program. It essentially acts as the brain of the PLC, processing inputs, controlling outputs, and executing logic to achieve the desired automation tasks.

The processor module typically consists of a CPU that performs the necessary computations and logic operations. It operates on a scan cycle, continuously reading input data, executing control logic as per the program, and updating output states. This is critical for real-time operation, allowing the PLC to respond quickly to changes in input conditions and adjust outputs accordingly.

Other components serve different but essential functions within the PLC. For instance, the I/O chassis houses the input and output modules that connect to field devices, allowing for signal transmission. Input modules specifically receive signals from sensors and other input devices, while output modules send signals to actuators and control devices. The power supply is crucial as it provides the necessary voltage and current to all components within the PLC system but does not engage in program execution. Thus, the processor module plays a pivotal role in executing the control logic that is fundamental to the operation of the