A controller setpoint is the target value a control system aims to maintain, such as a desired temperature in a refrigeration unit. Sensors report current conditions, and the controller adjusts equipment-such as compressors or fans-to move those conditions toward the setpoint.
In cyber security, setpoints matter because changing them can alter physical processes and affect safety, product quality, or equipment availability. In an attack, unauthorized access or a compromised control interface could be used to modify a setpoint; faults and legitimate maintenance can also cause unexpected changes. Defenders can restrict who may change control settings, monitor configuration changes, and compare setpoints with expected operating ranges. An unusual reading alone does not prove tampering: investigators need context about the sensor, equipment, and change history.