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lowest frequency output available from vfd

lowest frequency output available from vfd

lowest frequency output available from vfd

(OP)
Let's say were were doing a brief test and were not concerned about cooling or other effects on the motor.

What is the lowest frequency output available from a typical 480v 60hz-input VFD?

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RE: lowest frequency output available from vfd

You can command zero speed with a VFD so that would be the equivalent of 0 Hz.  The pulsing to the motor will actually vary slightly around zero but the net will be zero Hz or very near it.

RE: lowest frequency output available from vfd

Hi Electricpete

It does edpend on the VFD, some VFDs will operate right down to zero, while others switch the output off at around 0.5 Hz. I think that youwill find that the vector drives that can providetorque right down to zero Hz will give you this performance, while the V/Hz drives will tend to give no output at zero.

Best regards,

Mark Empson
http://www.lmphotonics.com

RE: lowest frequency output available from vfd

Remember that an induction motor must have slip to produce torque. If the motor is rated for full load torque 2% slip, it will need to have 2% of rated frequency to produce full torque at zero speed.

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