Possible Causes of Increased Noise after Rewind



Improper winding

Misalignment, uneven spacing, or poor insulation between turns can create magnetic imbalances and cause noise.

Uneven air gap

Differences in the distance between the stator and rotor can result in magnetic pull and increased noise.

Bearing issues

Rewinding may have affected the bearing alignment, lubrication, or condition.

Rotor balance

An unbalanced rotor can introduce vibrations that can amplify noise.

Resonance

Changes in the winding or other components may have shifted the motor's resonant frequency, making it more susceptible to noise.

Additional Checks in Service



Motor current harmonics

Use a power analyzer to measure current harmonics. Excessive harmonics can indicate winding issues.

Vibration analysis

Perform vibration measurements at various points on the motor to identify any abnormal vibration patterns.

Temperature monitoring

Check stator and bearing temperatures using infrared thermography. Excessive temperatures can indicate winding problems or bearing issues.

Magnetic field measurements

Use a gauss meter to measure the magnetic field around the motor. Uneven magnetic fields can indicate winding imbalances.

Power factor

Measure the motor's power factor. A low power factor can indicate certain types of winding issues.

Recommendations: Contact the rewind shop for their assessment and possible solutions. Perform a thorough visual inspection of the motor, paying attention to winding connections, insulation, and bearing condition. Consider performing a partial rewind to replace only the affected portion of the windings. Check the motor's mounting to ensure it's secure and not contributing to vibrations.* Consult with a motor expert for further troubleshooting and recommendations. Flag for review