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 and
is on the way to failing. Substitute another one of as near the right
value as possible and see if that stops or alters the noise. (Make sure
the capacitor is discharged each time before touching it.)


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~ Adrian Tuddenham ~
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