Electric Motor Requiring More Power


Old 01-28-19, 01:56 PM
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Electric Motor Requiring More Power

I have a 10 hp 3 phase lift motor that has been used for running lifting jacks. A year and a half ago it would operate off of a 16 KW generator now it requires 40 +KW generators.

Everywhere I have taken it cannot figure out why or how this is happening.

Does anyone have any suggestion on cause/repairs?
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Old 01-28-19, 07:26 PM
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Have you verified the motor is drawing more than the nameplate amps at the stated voltage and frequency. Did you use a true RMS meter? How did you measure the frequency of the generators?
Old 01-29-19, 01:09 AM
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If the electric motor is requiring more power to operate, then it is shorting internally or the load applied to it is increased. Is the motor getting hot too? A third option is bearing problems, but if the bearings were bad enough to require over two times the current, then the sound would surely be very obvious. If the load is not higher than it should be, then the windings are shorting and/or the rotor is shorted.
Old 01-29-19, 07:25 AM
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There is no additional noise for the bearings. I suspect it may be the windings, is a visual inspection best to see if this is the cause?

Im not sure what you me by "the load applied to it is increased".
Old 01-29-19, 08:29 AM
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The first thing I would suggest is to measure and record the amperage of each leg with a clamp on ammeter while the motor is under full load.
Compare the reading to the nameplate rating.

Then also measure and record the voltage between each of the 3 legs with the motor under full load..

This would be the starting point of troubleshooting your problem.

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