A variable frequency drive (VFD) fails to vary the discharge-air fan speed. A motor overheats and fails prematurely. Programmable controls that generally operate without issue suddenly experience ...

The way we control the speed of fan motors or pump motors has tremendously changed in the past two decades with the introduction of variable-frequency drives (VFDs), aka variable-frequency controllers ...

What if a variable-frequency drive (VFD) on a critical system has a fault indication, the “error” LED on a DC power supply has turned on, or a conveyor belt has started behaving erratically — most ...