Cascade control utilizes how many controllers and transmitters?

Cascade control involves a system configuration where one controller is used to manage a secondary control loop, while the primary control loop is governed by another controller. In this setup, there are typically two controllers: the primary controller regulates the main process variable, while the secondary controller controls a setpoint for the primary controller based on another variable.

The use of one transmitter is essential in this scenario as it provides the necessary measurement for the secondary loop's primary controller to adjust its output correctly. The primary controller uses output from the secondary controller to maintain the overall system performance. This arrangement allows for improved stability and response times in complex processes, as adjustments are made at multiple points in the control system.

Thus, the configuration of two controllers working together with a single transmitter forms the backbone of cascade control, making it an effective method for managing processes that require fine-tuned control.