Powering a 250 VDC Motor with 390 VDC – Questions?

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A 250 VDC motor was observed drawing 390 VDC, leading to confusion about voltage and current. It was clarified that motors do not "draw" voltage, and the voltage regulator may need adjustment. Despite the higher voltage reading, the motor's speed remained unchanged, raising questions about the current draw and the supply's capability. An initial misreading was attributed to an analog meter incorrectly set to the AC volts scale. Ultimately, the electrician's meter was confirmed to be improperly calibrated, resolving the issue.
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A 250 VDC motor drawing 390 VDC!
any one with any explanation?

Thanks.
 
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EEFinder said:
A 250 VDC motor drawing 390 VDC!
any one with any explanation?

Thanks.

Motors do not "draw" voltage...
 
Thanks for the reminder, I used the wrong word, and it is not current

the Voltage reading instead of being around 250VDC, it was around 390VDC
 
Adjust the voltage regulator. Is the speed OK at 390VDC, motor speed at constant load is proportional to voltage.
 
thanks for the replay,

and that's what baffled me, the speed looked unchanged!
 
EEFinder said:
thanks for the replay,

and that's what baffled me, the speed looked unchanged!
What's going on with drawn current?
 
? What is nature of supply? Is it capable of 390 volts ?

An analog meter that's set to AC volts scale will report high if connected to DC volts.
 
Jim,
That was actually the case.
By the end of the day on Thursday one of the electrician reported the situation. when I checked it on Friday morning, as well as few other times during the day, it was right on the money. When reviewed the Situation with the electrician, he stated that he was not sure if his meter was sat on DC!
 
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