Test A Fuse

There are multiple way to check proper operation of a fuse. The easiest being with a multimeter.
Here’s how to test your fuse, the right way.

Caution

It is very dangerous to surround a blow fuse with foil. This would remove any safety from your electrical system and exposes you to strong fire risks.

1. Remove the fuse

It is advisable to turn off power at the main circuit breaker before removing your fuse cartridge holder.

2. Select the right fuse tester

A fuse tester is a cheap tool, easy to use, and specifically designed for this purpose.
To check the status of a fuse with a tester, simply place the fuse in the device. If the fuse is bad, the tester won’t light up.

You can also obtain a multimeter. Inexpensive, it can be analog or digital. The multimeter is versatile device that is used by the DIY crowd to measure multiple things, including:

• tension
• intensity
• conductor resistance

3. Set the multimeter

The advantage of a digital multimeter is that it is self-protected. It won’t burn off because of mishandling.
Connect the two leads from the multimeter to the terminals of the controller. For this type, color order does not matter.
Switch the device to “check diode” function. The screen should display the value 1.
Put both ends together to ensure proper operation of the multimeter. The display should read zero. If this is not the case, replace the battery of the device.

4. Test the fuse

Put the contact pins against the two ends of the fuse.
Fuse working: there will be system continuity if the screen displays the value 0, or it emits a continuous sound.
Fuse is blown: the fuse is dead if the display shows the value 1 or no sound is heard.
Some fuses are fitted with control pellets that self-destruct when they are blown. They are easily identifiable.

5. Testing without a muultimeter

To test a fuse without multimeter, take a flashlight equipped with a flat battery. Unscrew the bulb and get the battery. Place the fuse of one of the battery “blades” and the base of the bulb on the other side of the fuse. Put the bulb pad in contact with the second “blade” of the battery. If the bulb lights up, the fuse is good. There is no risk because the battery voltage is extremely low.