This article compares three schemes of fan control used on large air conditioning and refrigeration condensers. The first scheme is step control; the second is a hybrid with a VFD on only one bank of ...

For motors controlled by a variable frequency drive (VFD), the control method used in large part determines a motor’s efficiency and performance in an application.

A Variable Frequency Drive (VFD) regulates the speed of a 3-phase AC electric motor by controlling the frequency and voltage of the power it delivers to the motor. These devices, also known as ...