How PV Fuses Work

Normal Operation: A PV fuse contains a wire that can safely carry the normal current of the solar system without overheating.
Fault Condition: If an electrical fault occurs (like an overload or short circuit), the current in the circuit rises above the fuse’s rated value.
Fuse Activation: The excessive current causes the internal wire of the fuse to heat up, melt, and break.
Circuit Interruption: When the wire breaks, it opens the circuit, stopping the flow of current and protecting the system’s components.

Key Considerations

Specialized Design: PV fuses are specialized for solar applications and are often rated to interrupt higher DC voltages compared to standard fuses.
Proper Sizing: Selecting the correct fuse size is crucial. It should be rated to handle the specific current of the PV strings to provide effective protection.
Location: PV fuses are typically installed in combiner boxes or disconnects to protect the array and other components.