What Exactly is an Electrical Fuse?

BY: CableOrganizer.com


The easiest way to start this article is with a short concise answer: An electrical fuse is a current interrupting device which protects an electrical circuit in which it is installed by creating an open circuit condition in response to excessive current.

When the element in a fuse receives too much heat it will melt and interrupt the current. Fuses are usually used as a conduit between an electrical power source and an electrical component or a combination of components arranged in an electrical circuit. A fusible link is connected between the fuse terminals. This means that when an electrical current passing through the fuse goes beyond what the device is able to handle, the fusible link will melt and the circuit opens thus preventing electrical component damage.

Fuses are typically made for single time use. In other words, once it shuts a device down it must be replaced. You can get over-current protection from a variety of sources such as circuit breakers, switches, and relays. Each type of equipment has variations in ratings, service requirements and costs. Fuses are typically the most economical means for providing automatic high-voltage current protection against a single over-current failure.

Cooper Bussmann J600 Series Fuse Blocks

Fuses are part of electrical systems in cars, trucks, boats, motorcycles and other types of vehicles. These fuses function to stop electricity from flowing to a particular component of the system by creating an open circuit as a result of an unsafe electrical condition. In the utility industry, you will find fuses used in distribution transformers, cables, capacitor banks and other equipment from damaging over currents. Fuses are utilized in such a way that the disconnect will occur before damage can harm your systems. Fuses are used quite a bit in high voltage electrical networks in order to protect the electrical equipment in the network from damage caused by surges through the system.

There are many types of fuses, we have listed a few below:

  • Thermal fuses
  • Mechanical fuses
  • Blade fuses
  • Expulsion fuses
  • Spark Gap Surge Arrestors
  • Varistors

Each fuse is designed specifically as a solution to one or more extreme electrical events. In general, an electrical fuse combines both a sensing and interrupting element in one self-contained device.