What device automatically protects an electrical system from short circuits and overloads?

What device automatically protects an electrical system from short circuits and overloads?

• A. Resistor
• B. Fuse
• C. Circuit breaker
• D. Transformer

Answer: (C)

The device that automatically protects an electrical system from short circuits and overloads is the circuit breaker. Circuit breakers are designed to interrupt the flow of electricity when they detect a fault, such as an overload or a short circuit. This interruption helps prevent overheating and potential fire hazards caused by excessive current.

When an overload occurs, the circuit breaker trips, cutting off the electrical supply to the circuit. This action is crucial for maintaining safety in electrical systems, as it reduces the risk of damage to wiring and connected devices. Unlike other options listed, circuit breakers can be reset after they trip, allowing the electrical system to be restored without needing to replace any components.

While fuses also provide protection against overloads and short circuits by blowing and breaking the circuit, they must be replaced after they have operated, unlike circuit breakers which can be reset. Resistors and transformers do not serve the protective function of disconnecting the circuit during faults; instead, resistors limit current flow, and transformers change voltage levels in electrical systems.