Motor Bearing Fault

Motor bearing fault detected by online monitoring of an air handling unit motor

Motor Bearing Fault Detected in Air Handling Unit Motor

Air Handling UnitInspection description: Vibration analysis inspection of Motor Drive
Frequency of inspection: Continuous 24/7 Online Monitoring and Remote Analysis
Equipment description: Motor – Belt – Fan running 24/7

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing 11-12-2015

Image 1

This spectrum indicates the normal operating vibration baseline of the Motor Drive Bearing.

Vibration trend (Acceleration Route Mean Squared) from the Motor Drive End Bearing recorded in October 2015 to February 2016

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This trend spectrum indicates the normal operating vibration baseline from the Motor Drive Bearing and an increase in vibration end of December 2015 and January 2016.

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing recorded 14-01-2016.

Image 3

This spectrum indicates an increase in the overall high frequency vibration that has occurred in the Motor Drive bearing.

Fault detection and action

Fault detected: Deterioration detected of the Motor Drive Bearing

Action: The online system raised a warning notification. Remote analysis determined a low level issue had been detected. A report was issued to site personnel.

Recommended Action:  Visually inspect motor and continue to monitor.

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing recorded 29-01-2016:

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This spectrum indicates the overall high frequency vibration has continued to increase in the Motor Drive bearing.

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing recorded 31-01-2016:

Image 5

This spectrum indicates the overall high frequency vibration has continued to increase in the Motor Drive bearing. Within two days a secondary peak had formed.

Fault detection and action

Fault detected: Further deterioration detected of the Motor Drive Bearing

Action: The online system raised an alarm notification. Remote analysis determined the severity of the issue had progressed to a high level. A report was issued to site personnel.

Recommended Action: Replace Motor Drive Bearing.

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing recorded 01-02-2016:

Image 6

This was the last reading taken before repairs were carried out. The spectrum indicates the overall high frequency vibration has continued to increase in the Motor Drive bearing, note the increasing level of the second peak.

Repairs carried out

Repair works were carried out on 02-02-2016 and the Motor Drive Bearing was replaced.

Vibration reading (Acceleration Spectrum) from the Motor Drive Bearing recorded 17-02-2016:

Image 7

The spectrum indicates the overall high frequency vibration is no longer present in the Motor Drive bearing after the bearing was replaced.

Summary Vibration trend (Acceleration Route Mean Squared) from the Motor Drive Bearing recorded between October 2015 to June 2016:

Summary Vibration Trend Before and After

This RMS trend indicates the before and after vibration levels of Motor Drive Bearing between October 2015 and June 2016.