Page 50 - Testing Electronic Components

Testing Fuse

Typical example of fuses

It’s very easy on how to test a fuse. Fuse is a very thin wire, which either
melts or vaporizes when current flow through it exceeded the fuse rating.
The thin wire of fuse may be made of aluminium, tin-coated copper or
nickel. The resulting open in the circuit stops current to flow. In
electronic equipment, most fuses are cylindrical glass or ceramic type
with a metal cap at each end! The current rating and voltage also can be
seen in one of the two metal end caps.

There are two popular physical sizes: 1 – ¼ X ¼ - inch and 5X20mm.
The 1 – ¼ X ¼ - inch size is used in many automobiles. You’ll find both
sizes in many electronic equipment, but the smaller 5 X 20mm has
become more common. Fuses are available with current ratings from
1/500 Ampere to hundreds of amperes. Fuse is label as “F” in circuit
board.

Before showing you on how to test or check a fuse, first you need to
understand the purpose of a fuse. The function of fuses is to stop higher
than normal current to flow to an electronic circuit-it is designed to
protect equipment and save electronic components from being damaged

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