A homeowner reports flickering lights and occasional tripping of the main breaker, especially when heavy loads like a well pump or electric stove are active. The electrician suspects a problem with the service connection. What type of conductor fault is most likely causing these symptoms?

Question: A homeowner reports flickering lights and occasional tripping of the main breaker, especially when heavy loads like a well pump or electric stove are active. The electrician suspects a problem with the service connection. What type of conductor fault is most likely causing these symptoms?

Answer options:

• Solid ground fault
• Phase-to-phase short circuit ✅ Open neutral connection
• Reverse polarity on a receptacle

Correct answer: Open neutral connection

Explanation: Flickering lights and intermittent tripping, particularly with varying loads, are classic symptoms of an open neutral connection in a multi-wire branch circuit or at the service entrance. Without a solid neutral path, load imbalances cause voltage fluctuations across the ungrounded conductors, leading to over-voltage on lightly loaded phases and under-voltage on heavily loaded phases. A solid ground fault or phase-to-phase short circuit would typically result in an immediate and sustained trip of the breaker, not flickering lights, while reverse polarity on a receptacle might affect a single appliance but not the entire dwelling.