What are the major components of a PLC system?

What are the major components of a PLC system?

• A. Processor, input assembly, output assembly, and power supply.
• B. CPU, memory, I/O interface, and power supply.
• C. Sensor, actuator, controller, and network.
• D. Display, keyboard, mouse, and printer.

Answer: (A)

The major components of a PLC system are the processor (the brain), the input assembly, the output assembly, and the power supply. The processor runs the control program and makes decisions based on the input signals it receives. The input assembly brings in signals from sensors and switches, turning real-world conditions into data the processor can use. The output assembly takes the processor’s decisions and converts them into actions, such as turning a motor on or a valve open. The power supply provides the necessary electrical power to all parts of the PLC so they can operate reliably. This combination covers sensing, processing, action, and power, which are the fundamental building blocks of a PLC. Other options may mention memory or interface details, but those are usually considered parts of the processor or the I/O subsystems rather than separate major blocks in the basic description.

The major components of a PLC system are the processor (the brain), the input assembly, the output assembly, and the power supply. The processor runs the control program and makes decisions based on the input signals it receives. The input assembly brings in signals from sensors and switches, turning real-world conditions into data the processor can use. The output assembly takes the processor’s decisions and converts them into actions, such as turning a motor on or a valve open. The power supply provides the necessary electrical power to all parts of the PLC so they can operate reliably.

This combination covers sensing, processing, action, and power, which are the fundamental building blocks of a PLC. Other options may mention memory or interface details, but those are usually considered parts of the processor or the I/O subsystems rather than separate major blocks in the basic description.