Which condition can trip the generator off by the GCU due to generator and bus overcurrent?

• A. Generator and Bus Overcurrent
• B. Over/Under Voltage
• C. Phase sequence
• D. Low oil pressure

Answer: (A)

Overcurrent protection is designed to shut down the generator when current exceeds safe limits, protecting the windings and the bus. When a fault occurs, such as a short circuit on the generator or on the bus, the current rises rapidly. The GCU detects this elevated current (typically via current transformers) and trips the generator to prevent damage from overheating, insulation stress, or bus equipment failure. Other conditions—voltage deviations, incorrect phase sequence, or low oil pressure—trigger protection for different failure modes (voltage stability, mechanical issues, or incorrect phasing), not the generator-and-bus overcurrent scenario. So the condition that can trip the generator off the GCU due to generator and bus overcurrent is the overcurrent itself.