Red Seal Powerline Technician Practice Exam

What device is used to protect electrical circuits from overload?

1. Transformer

2. Circuit breaker

3. Fuse box

4. Voltage regulator

The correct answer is: Circuit breaker

A circuit breaker is designed specifically to protect electrical circuits from overload and short circuits. It automatically interrupts the flow of electricity when it detects a current that exceeds a predetermined level, thereby preventing potential damage to the electrical system, appliances, and devices connected to it. This operational feature is crucial as an overload can lead to overheating and possible fires, making the circuit breaker an essential safety device in any electrical system. In comparison, a transformer is used to change the voltage level in an electrical system and does not provide overcurrent protection. A fuse box contains fuses that also serve to protect against overloads, but fuses must be replaced once they blow, while circuit breakers can be reset and reused. A voltage regulator maintains the voltage at a constant level but does not address issues related to current overloads. Hence, the circuit breaker is the most effective device for protecting electrical circuits from overload conditions.