What is the primary function of a circuit breaker?

The primary function of a circuit breaker is to interrupt current flow during fault conditions. This is essential for protecting electrical circuits and devices from damage caused by overloads, short circuits, or faults within the system. When a fault is detected, the circuit breaker automatically opens the circuit, stopping the flow of electricity and thereby preventing potential hazards such as fires, equipment damage, or electric shock.

In this context, while connecting power sources is an aspect of electrical systems, it is not the primary function of a circuit breaker. Similarly, providing an emergency disconnect is important, but it is more of a supplementary feature than a primary function. Monitoring power quality is crucial for energy management and system efficiency, but it falls outside the core responsibility of a circuit breaker, which is to ensure safe operation by interrupting current under fault conditions.