In a feedback control system, which component is responsible for comparing the output to the setpoint?

In a feedback control system, the controller plays a pivotal role in ensuring that the output conforms to the desired setpoint. The controller receives input signals from the sensor that measures the current output value and compares it against the predetermined setpoint, which is the target value the system aims to achieve. This comparison is crucial because it allows the controller to determine the error—essentially, the difference between the setpoint and the actual output.

Once the controller calculates this error, it can then decide how to adjust the system's input, typically by sending signals to the actuator, to minimize the error and bring the output closer to the setpoint. This process is continuous, resulting in a dynamic response to changes in the system or external factors, thereby enhancing stability and performance.

The other components have distinct roles: the actuator implements the control actions determined by the controller, the sensor measures the system's output, and the transducer converts one form of energy to another, facilitating the measurement and control processes. Therefore, understanding the controller's function in this feedback loop is essential for grasping how automated control systems operate effectively.