Adrian Tuddenham wrote:

Peter Jason wrote:

4-pole 3Ph squirrel -cage motor noisy.

A loud buzzing noise has developed over the past
12 months. The motor is not overheating, nor are
the bearings.

Is this serious?

If it has a phase-shift capacitor, that has probably changed value ...

My apologies, I didn't spot that you had said it was 3Ph.

It could be one phase disconnected, although that probably would make
more of a hum than a buzz. Laminations could be working loose in the
rotor or the windings working loose in the stator; the former will be
more likely to change on load or pulsate at slip frequency.

--
~ Adrian Tuddenham ~
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