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Selection and use of a VFD for service center testing

  • January 2016
  • Number of views: 11421
  • Article rating: 5.0

Art Godfrey (retired)
Birclar Electric & Electronics
Romulus, Michigan
Technical Services Committee Member

With the growing popularity of variable frequency drives (VFDs), it is likely almost every EASA service center has repaired motors powered by one in a customer’s installation. For these motors, it is best that after repair they are tested using a VFD, typically at no-load. This will provide operation mimicking the actual customer applica­tion, at varying speeds, and will help ensure proper mechanical operation throughout the speed range. This will include detecting vibration problems, identifying any resonant speeds within the operating range, and more. Also, if the motor is used above utility line fre­quency (i.e., 50 Hz or 60 Hz), it should be operated up to top speed for vibra­tion measurement and a good break-in of the bearings.

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ANSI/EASA AR100

More information on this topic can be found in ANSI/EASA AR100
  • Section 4: Testing

EASA Technical Manual

More information on this topic can be found in EASA's Technical Manual
  • Section 2: AC Machines
  • Section 5: Electronics

Related Reference and Training Materials

Principles of Medium & Large AC Motors (NEMA Standards)
  • Section 6: Motor Standards
  • Section 7: Stators

Principles of Medium & Large AC Motors (IEC Standards)
  • Section 6: Motor Standards
  • Section 7: Stators

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