In an electronic controller with a narrow proportional band setting, what effect does a small movement have?

In an electronic controller with a narrow proportional band setting, a small movement of the controlled variable results in a large unbalance. This is because a narrow proportional band means that the controller is highly sensitive to changes. In such configurations, even minor deviations from the setpoint can trigger a significant correction action by the controller.

This sensitivity is designed to allow for precise control within a very specific range but can also lead to larger swings in response to small changes, creating an unbalance as the controller reacts strongly to maintain the desired setpoint. Such responses can lead to oscillations or instability in some situations if not managed properly.

In contrast, a wider proportional band would result in a more gradual response to changes, leading to less pronounced shifts in controller action for small disturbances.