Fuses: Learn About Fuses Here >
is a reliable overcurrent protective device, primarily used as a circuit protection
device for overcurrents, overloads and short-circuits. A "fusible" link or links encapsulated in
a tube and connected to contact terminals comprise the fundamental elements of the basic
fuse. Electrical resistance of the link is so low that it simply acts as a conductor. However,
when destructive currents occur, the link very quickly melts and opens the circuit to protect
conductors and other circuit components and loads. Fuse characteristics are stable. A fuse
does not require periodic maintenance or testing. The fuse has three unique performance
- They are safe. The modern fuse has an extremely "high interrupting" rating-can withstand very high fault currents without rupturing.
- Properly applied, a fuse will prevent "blackouts." Only a fuse nearest a fault opens without upstream fuses (feeders or mains) being
affected, thus, they provide "selective coordination." (These terms are precisely defined in subsequent pages.)
- A fuse provides optimum component protection by keeping fault currents to a low value... They are said to be "current limiting."