Usually yes, but inverter operation puts an old motor into new conditions: fast voltage pulses, reduced cooling at low speed and possible bearing currents. A motor that ran for years without trouble on the mains may show its weak point under these new conditions.

Check the following before deciding:

  • Nameplate: Do the voltage and connection suit the inverter output (230/400 V or 400/690 V)?
  • Insulation: The winding insulation resistance should be measured; for motors that have been rewound, the material used may be unknown.
  • Cable and filter: On a motor with uncertain insulation, a dv/dt or sine filter becomes even more important.
  • Speed range: If there is long operation at low speed, is the existing fan sufficient?
  • Bearings: Noise and vibration condition; bearing current measures on large frames.

If the motor's condition is uncertain or the cost of extra measures is high, a new motor configured for inverter use may be more economical. You can get an equivalent model suggestion by sending a photo of the existing motor's nameplate.