Engineering · Electrical — Motors
An induction motor that hums but will not start, then overheats, most likely has:
- AToo high a supply voltage
- BSingle-phasing (loss of one phase)✓ Correct
- CExcess lubrication
- DA reversed rotation
Explanation
Loss of one of the three phases (single-phasing) leaves the motor unable to develop starting torque; it hums and draws heavy current, overheating quickly. Protection should trip it.
Authority: Marine Electrical (USCG engineering topic)
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