What happens when a fuse blows in a circuit?

When a fuse blows in a circuit, it serves as a protective device that disrupts the flow of electricity. The primary function of a fuse is to prevent overcurrent, which can cause damage to electrical components or create safety hazards such as fires. When the current exceeds a designated limit, the fuse melts or breaks the internal connection, effectively acting as a break in the circuit.

This interruption halts the flow of electricity, ensuring that no excess current can reach the electrical devices downstream. As a result, the circuit is no longer operational until the blown fuse is replaced. This mechanism is crucial for maintaining the safety and integrity of electrical systems in HVACR applications and beyond.