What could cause a shore-power ELCI main breaker to trip?

A shore-power ELCI (Earth Leakage Circuit Interrupter) main breaker is designed to protect against ground faults by monitoring the current flowing through the live and neutral conductors. When these currents are not balanced due to leakage or fault conditions, the ELCI will trip to prevent potential electric shock or fire hazards.

The situation described where multiple shore-power inlet neutral conductors on the load side of the ELCI are connected can create an imbalanced condition that the ELCI detects. This configuration can lead to situations where the leakage currents do not balance correctly, causing the ELCI to trip as a safety precaution. The interruption of the circuit is a protective response to ensure user safety and the integrity of the electrical system.

In contrast, exceeding the maximum current limit typically results in a different type of breaker tripping; this wouldn’t specifically trigger the ELCI function. Improper grounding of the ELCI can also lead to tripping under certain conditions, but it primarily affects safety and equipment performance rather than the immediate ground fault detection the ELCI provides. A faulty shore power plug may present connection issues but does not directly cause the ELCI to trip unless it creates a fault condition.