Trying to save energy dollars isn't always as simple as it seems. Installing variable-frequency drives (VFDs) and retrofitting lighting systems are two of the quickest and most widely accepted ways to ...

Increasingly common, variable frequency drives (VFDs) are used to control motor speed — elevating the frequency of power pulses/sec fed to motors for faster turning, and decreasing that frequency to ...

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 ...

A VFD reports a low-volts fault when the drive's dc link voltage drops below 62% of the nominal level for the high setting (480 Vac) and 50% of nominal for the low setting (400 Vac). The +10% and -15% ...