Variable Frequency Drive

variable frequency drive is a type of adjustable-speed drive used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and voltage. VFD are used in applications ranging from small appliances to large compressors. About 25% of the world's electrical energy is consumed by electric motors in industrial applications, which can be more efficient when using VFD in centrifugal load service

VFD Buying Guide

Finding the perfect VFD or motor controller can be a fairly daunting task as there are many variables with each application and system. However, below are some helpful tips and suggestions to help you select the right drive. Before you get too far into the process of looking at VFDs, it is a good idea to gather the basic motor and system information that will help you in selecting the proper VFD. Most of this information can be found on your motor nameplate such as:

  • Horsepower
  • Full Load Amps (FLA)
  • VoltageRPM
  • Service Factor
  • It is also helpful to know if the motor is inverter duty rated


Other information will be specific to the needs of your system and application such as:

  • Type of Load (Constant Torque or Variable Torque)
  • Speed Range and Control Method
  • Special Enclosure Needs