What PLC feature primarily enables behavior changes without hardware modifications?

What PLC feature primarily enables behavior changes without hardware modifications?

• A. Memory
• B. I/O
• C. Program
• D. Power supply

Answer: (C)

Changing the PLC’s behavior without touching the hardware comes from the control program stored in memory. The program defines the logic that reads inputs and decides which outputs to energize. By editing that program and downloading the new version to the PLC, you alter how the system behaves while the physical hardware—sensors, actuators, wiring, and power—stays the same. Memory is the storage for the program and data, but it’s the program itself that enables behavior changes. I/O and power are about interfacing with the world and supplying energy, not about changing how the system operates without hardware modifications.

Changing the PLC’s behavior without touching the hardware comes from the control program stored in memory. The program defines the logic that reads inputs and decides which outputs to energize. By editing that program and downloading the new version to the PLC, you alter how the system behaves while the physical hardware—sensors, actuators, wiring, and power—stays the same. Memory is the storage for the program and data, but it’s the program itself that enables behavior changes. I/O and power are about interfacing with the world and supplying energy, not about changing how the system operates without hardware modifications.