| B1: Are vibrations and noise from driven machine
or power transmission system being transmitted to motor? |
 |
Locate source of noise
and reduce. Isolate motor with belt drive or elastomeric coupling. |
 |
|
| B2: Is a hollow motor foundation acting as
a sounding board? |
|
Redesign mounting.
Coat foundation underside with sound dampening material. |
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|
|
| B3: Check motor mounting. Is it loose? |
|
Tighten. Be sure shaft
is aligned. |
|
|
|
| B4: Is motor mounting even and shaft properly
aligned? |
 |
Shim feet for even
mounting and align shaft. |
 |
|
|
| B5: Is fan hitting or rubbing on stationary
part or is object caught in fan housing? |
|
Repair damaged fan,
end bell or part causing contact. Remove trash from fan housing. |
|
|
|
| B6: Is air gap nonuniform or rotor rubbing
on stator? |
|
Recenter rotor rubbing
on worn bearings or relocate pedestal bearings. |
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|
|
| B7: Listen to bearings. Are they noisy? |
|
Lubricate bearings.
If still noisy, replace. |
|
|
|
| B8: Is voltage between phases (three-phase
motors) unbalanced? |
|
Balance voltages. |
|
|
|
| B9: Is three-phase motor operating on one-phase?
(Won't start on single-phase.) |
|
Restore power on three-phases. |
