In a cascade control loop, what does the primary control loop determine for the secondary control loop?

In a cascade control loop, the primary control loop is responsible for establishing the setpoint for the secondary control loop. The primary loop reacts to the overall system's performance to ensure that the desired process variable remains at the desired value. By effectively setting a setpoint for the secondary loop, the primary control loop allows the secondary loop to focus on more specific or immediate process adjustments.

This hierarchical approach allows for better control and stability in processes that have multiple variables influencing the outcome. The secondary control loop then can adjust its parameters more finely based on the setpoint provided by the primary loop. The setpoint acts as the target value or reference that the secondary control loop aims to maintain, ensuring the overall system operates efficiently and effectively within the desired parameters.