Troubleshooting Your VFDs Aug 1, 2000 12:00 PM, By Stan Turkel
Find more articles on: Variable Frequency Drives Variable-
frequency drives (VFDs), also known as adjustable-speed drives
(ASDs) have become the preferred method of controlling speed to
meet load requirements. The most common drives use a pulse width
modulation (PWM) design, which is affordable, reliable, and cost
effective for most applications. While simple in their design,
they can give you problems when it comes to taking operational
and troubleshooting measurements. Knowing what measurements to
take will save you time and money. You'll need this type of
testing for troubleshooting and diagnosing a defective unit as
well as when performing routine maintenance. Where do you start
taking measurements? The four main aspects for testing a drive
system are the building's power supply, the drive unit itself,
the motor, and the load. Each item in a drive system works
together and becomes the entire drive application. This creates
a potential problem: