What is a setpoint?

• A. A target value to be achieved during testing
• B. A desired value that is to be controlled in a process
• C. An average value computed by the controller
• D. The maximum allowable deviation

Answer: (B)

In a control system, the setpoint is the reference value the system tries to reach and maintain for a process variable. It’s the desired value that is to be controlled in the process, and the controller continuously compares the actual measurement to this target to generate an error signal that drives adjustments. For example, a temperature setpoint of 75°C tells the system to heat or cool until the temperature matches 75°C. This isn’t the measured average or the maximum allowable deviation; those describe other ideas like averaging data or tolerance limits. The setpoint can be fixed or can change over time according to a schedule, but it always represents the intended operating value that the controller aims to achieve.