It sounds like the problem is in the drive. Is your incomming supply OK?
Check the motor over, brushes etc, and do a resitance check of the field and check for loose connections etc.
The field voltage should be constant, some drives have what is called field weakening, the field voltage is reduced to attain high rpm, this only occurs after a certain high rpm.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |