Multi-Loop & Cascade Control

A real building runs dozens of control loops at once: valves, dampers, pump speeds, boiler and chiller stages, zone temperatures. Left uncoordinated they interfere, and the most expensive interference of all is heating and cooling running in the same space at the same time, each fighting the other while both meters spin. Multi-loop control is the discipline of stacking and coordinating loops so they cooperate. This lesson covers the two structures that matter: cascade control, which stacks loops, and coordination, which stops them fighting.