Fuses are electrical safety devices which contain a "link" that melts at a pre-determined electrical current. The link melts because of the heat produced by excessive amounts of current flowing through it. When the fuse link melts, it opens the circuit and shuts off the current flow.
There are two basic fuse types:
- plug fuses, sometimes called screw-base fuses;
- and cartridge fuses.
Plug or screw-type fuses are typically used in smaller sizes up to about 30 amps but are made in larger sizes, too. Cartridge fuses are normally found in very small electrical devices and are also used on high current-carrying circuits over 30 amps or more in electric wiring applications. Both types are made in non-delay and time-delay -- also called "slow blow" -- designs.
