Sometimes these control loops are nested and/or cascading – whereby when multiple sensors are available from measuring conditions in a controlled process, a cascade control system can often perform better than a traditional single-loop. For example, the steam-supplied water heater shown heats water using cascade control. The second controller has taken over responsibility of manipulating the valve opening based on measurements from a second sensor monitoring the steam flow rate.
Copyright: Cybersecurity & Infrastructure Security Agency (CISA)