Fuse Monitor / Alarm

It came to me in a flash. A simple way to see if a fuse has blown without removing it from its holder. Its not often you can design a circuit using just two components, but with just one resistor and an LED this circuit provides visual indication of when a fuse has blown.

The described circuit provides a straightforward method for indicating the status of a fuse using minimal components. The primary components involved are a resistor and a light-emitting diode (LED).

The circuit operates by connecting the LED in parallel with the fuse. When the fuse is intact, current flows through the fuse, allowing the LED to remain off due to insufficient voltage across it. The resistor is placed in series with the LED to limit the current flowing through it, ensuring that the LED operates within its specified current rating and does not get damaged.

In the event that the fuse blows, the circuit's behavior changes. With the fuse open, the current can no longer flow through the fuse path. However, the LED will now receive voltage from the power supply directly across its terminals, causing it to illuminate. This visual indication serves as a clear and immediate alert that the fuse has blown, allowing for quick identification and replacement without needing to physically remove the fuse from its holder.

For optimal performance, the resistor value should be calculated based on the supply voltage and the forward voltage drop of the LED, ensuring that the LED receives the appropriate current for visibility. This simple yet effective design exemplifies the utility of basic electronic components in creating practical solutions for troubleshooting and maintenance in electrical systems.It came to me in a flash. A simple way to see if a fuse has blown without removing it from its holder. Its not often you can design a circuit using just two components, but with just one resistor and an LED this circuit provides visual indication of when a fuse has blown. 🔗 External reference