Topic: Braking Resistors for Variable Frequency Drives

Application: Regeneration of Variable Frequency Drives
When a drive unit is attempting to rapidly brake a motor “Deceleration Braking Cycle” or when an “overhauling load” condition exists, the spinning motor acts as a generator.

This freewheeling condition will force some voltage back into the drive unit (regeneration) which may cause an over voltage condition if the energy is not absorbed somewhere else.

Solution: Braking Resistors

Braking resistors are used to absorb energy that is being regenerated back into a drive unit by a freewheeling motor. The energy is released in the form of heat.

Filnor Braking Resistors are sized based on the following customer supplied information:
  • Voltage: DC bus Voltage
  • Drive horsepower
  • Braking Torque
  • Duty Cycle: On time/Off time
  • The maximum braking current or minimum ohmic value as specified by the drive manufacturer
  • Regeneration Type
  • Deceleration braking or Overhauling Load

See our full line of power resistors, disconnect switches and control equipment on our site and receive an online quote for standard products in our product line.


Since 1970, Filnor, Inc. has designed and manufactured products for industry world wide, including Mass Transit, Utilities, Power Generation, Steel, Telecommunications, Mining, Paper Mills, Aluminum Plants, Ship Building, Automotive and Construction. Filnor, Inc. consists of three product groups; Power Resistors, Disconnect Switches and Control Equipment.

Filnor Standard Braking Resistors

Filnor standard Braking resistors have the following features:
  • Well ventilated enclosure for indoor or outdoor applications
  • Wall or Roof Mount
  • Built-in Junction box with multiple conduit knockouts
  • Front Mounted Nameplate with complete ratings
Options Include:

Stainless steel enclosure, or special paint
Wired to a terminal block with high temperature wire
Thermal overload (N.C. or N.O. contacts)
Filnor can provide you with a complete list of standard braking resistors or quote you per your requirements. Please Contact Filnor for more information.