The fault is mainly caused by incorrect protection settings, reversed CT polarity, open CT secondary circuit and wrong logic configuration. Carry out secondary injection testing, cross-check with wiring diagrams, and test trip circuit continuity. Core idea: Protective relays monitor electrical quantities and command protective devices to isolate faults or abnormal operating conditions. This is why working with a reliable protection relay supplier and applying correct engineering practices during design, installation, and commissioning is. When a protection relay fails to operate during a real fault, the consequences can be severe — prolonged fault duration, equipment damage, and major production losses. Relay nuisance tripping (false relay operation / relay trips without fault) manifests as breaker tripping with no actual fault, unwanted relay pickup during motor startup and unplanned random equipment shutdown. While this is bad, It's not a.
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