Electrical failure is not one single failure mode. The pattern you find can help point you toward the conditions that need to be investigated before the system is restarted.
Common Electrical Failure Patterns
Electrical failures can present as general or uniform burn, single phase burn, half winding single phase burn, start winding burn, run winding burn and primary single phase burn.
Many motors fail as a result of a mechanical or lubrication failure and malfunctioning external electrical components. If failure is visible on the terminal plate, the cause is external to the compressor.
Common Causes to Investigate
- Voltage imbalance
- Low voltage
- Contactor failure
- Improper overload protection
Corrective Checks
- Verify proper voltage and phase balance
- Check all electrical connections for tightness and integrity
- Inspect contactors and overloads for proper operation and sizing
- Address underlying electrical supply issues before restarting
A replacement compressor will not solve an external electrical problem. Before restarting or installing another compressor, identify and correct the condition that caused the failure.
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