What is the main purpose of a circuit breaker?

• A. To automatically interrupt current during overload or short circuit to protect wiring and devices.
• B. To regulate voltage.
• C. To convert AC to DC.
• D. To store energy.

Answer: (A)

The main function of a circuit breaker is to automatically interrupt current when it rises to unsafe levels due to overload or a short circuit, protecting wiring and devices from damage. It detects abnormal current and trips, opening the circuit so electricity stops flowing beyond the fault. This quick action prevents overheating of conductors, insulation damage, and the risk of fires. After the fault is cleared, the breaker can be reset to restore power. It’s not meant to regulate voltage, convert AC to DC, or store energy—those roles belong to other devices such as regulators, rectifiers, or energy storage systems.