HOLT Electricians Practice Exam

If fuses are used for overload protection, what must be protected?

1. Each grounded conductor

2. Each ungrounded conductor

3. Each neutral conductor

4. All conductors collectively

The correct answer is: Each ungrounded conductor

For overload protection, specifically when using fuses, it is essential to protect each ungrounded conductor. Fuses are primarily used to limit the amount of current flowing through a conductor, and they are placed in series with the circuit. When a current overload condition occurs, the fuse will blow, interrupting the flow of electricity. Ungrounded conductors, often referred to as "hot" wires, are those that carry the current from the power source to the load. These conductors must be monitored individually to ensure that any overload on one does not result in damage to equipment or create a fire hazard. If only the grounded or neutral conductors were protected, the ungrounded conductors could experience overloads, leading to dangerous conditions since there would be no interruption of current flow. Collectively protecting all conductors might seem like a possible approach, but it fails to address the individual risks posed by overloads on specific conductors. The focus on ungrounded conductors is crucial for maintaining safety and preventing potential hazards associated with electrical overloads.