The FCS unit is an electronic voltage regulator that uses the phase-cutting principle to regulate the output voltage supplied to the load, according to an input control signal. It is used to control asynchronous axial electric motors (low capacity and class H, specific for phase-cutting control), such as fans etc. The FCS regulators have been designed to be managed by an electronic controller, which supplies a proportional 0 to 10 Vdc signal for the correct management of the speed controller.
For air-conditioning and refrigeration applications in particular, Carel have developed the FCM controller that integrates all the typical functions (cooling/heating control, minimum and maximum speed, cut off, speed up, defrost etc.) required for the correct operation of the electric motors. Otherwise, it is possible to send the 0 to 10 Vdc control signal to the FCS directly from other sources.