Ventilation speed controller FRA

The centrifugal fan Speed Controller are constructed to control single and multiple fan systems. Rotary transformer, servo motor and an electronic controller, motor contactor, on/off switch with control lights, secondary (output) fuses, all contained in a sheet steel housing. The required condition is called on the pre-set device and this is compared in the electronic control to the condition recorded from the actual value sensor. The servo motor then drives the rotary transformer up or down to vary the output voltage, thereby controlling the speed of the FISCHBACH disc rotor motor fan 0-100% which in turn produces the required pre-set condition.