Fuses and Industrial Circuit Breakers

Fuses and industrial circuit breakers both work to keep electrical devices functioning in a safe manner. Overcurrent protection devices are essential in electrical systems to limit threats to individuals and property.

What is a Fuse?

A fuse is a type of overcurrent protection device. The most important component of a fuse is a metal wire or strip that melts when too much current flows, which interrupts the circuit. The fuse interrupts blows so further damage, such as fire, is ultimately avoided. Overcurrent protection devices are essential in electrical systems to limit potential dangers to individuals and property. Fuses are selected to allow normal current to pass, as well as excessive current for only very short periods.

The Use of Fuses and industrial circuit breakers

While fuses alone are initially less costly, they are much more difficult to replace as opposed to simply resetting industrial circuit breakers. High rupturing capacity fuses can be rated to safely interrupt up to 300,000 amperes at 600 V AC. Often, special current-limiting fuses area applied ahead of some molded-case breakers in order to protect the breakers in low-voltage power circuits with high short-circuit levels.

Industrial circuit breakers should be tested and maintained on a regular basis to ensure their mechanical operation during an interruption. Fuses rely on a melting process where no mechanical operation is required for the fuse to operate under fault conditions.

Some medium-voltage distribution fuse manufacturers combine the overcurrent protection characteristics of the fusible element with the flexibility of relay protection by adding a pyrotechnic device to the fuse operated by external relays.

It is important when developing an electrical plan for a facility, that which type of component makes the most sense. Many choose to utilize industrial circuit breakers in order to have a reliable testing plan. It is critical however, that the decision be made in tandem with those who will be charged with keeping the electrical system online, functioning properly and safe.