Electrical Inspection, Testing and Certification Practice Exam 2026 – Comprehensive All-in-One Guide for Exam Success!

The correct choice involves the function of a circuit breaker, which is specifically designed to protect electrical circuits from overload conditions. When the current flowing through the circuit exceeds a predetermined limit, the circuit breaker automatically disconnects the electrical supply. This action prevents overheating and potential damage to the wiring and connected devices, effectively safeguarding the electrical system.

Fuses also serve a similar purpose by melting a wire inside when the current exceeds its rated capacity, thereby breaking the circuit. However, circuit breakers have the advantage of being resettable, whereas fuses need to be replaced after they have blown. This makes circuit breakers a more convenient and efficient choice for modern electrical systems.

Transformers do not prevent overloads; they are used to change the voltage level in an electrical circuit. Voltage regulators are designed to maintain a steady voltage level and do not specifically guard against overload situations. Thus, while both fuses and circuit breakers prevent overloads, the selectiveness of the correct answer points to the resettable and ongoing protection function of circuit breakers in general use today.