Overload Relays & Thermal Unit Selection

1. Overcurrent 30% 2. Contamination 18% 3. Single Phasing 15% 4. Bearing Failure 12% 5. Aging (natural wear) 10% 6. Rotor Fault 5% 7. Miscellaneous 7% Failure modes 1, 3 and 7 are attributable … ................
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