Fuse links

Fuse links

Fuse links are commonly used and absolutely required elements of every properly constructed electrical installation. They guarantee protection of power lines against overload, protect against fire, electric shock and reduce the consequences of failures.

Fuse links work on the principle of melting a conductive element (fuse), usually copper, sometimes silver-plated, placed in a closed housing. When a short circuit occurs in the electric system, the fuse heats up and the circuit is broken. Fuse links usually have a body made of soapstone, which is characterized by the best resistance to thermal loads, less often of high-quality ceramics. There may be quartz inside the fuse link. It reduces the electric arc that is generated during the fuse burning.

Fuse links - types

Fuse links are designed to protect electrical installations against short-circuits and overloads. They cooperate with fuse bases, fittings and sockets. Depending on the purpose and type of electrical installation, the appropriate type of insert is used.

NH fuse link is used, among others, for the protection of wind and solar power plants, electric motors, power networks and other industries. NH fuse links often have the function of signaling their activation status.

Type D fuse link is most often used in low power installations. It is commonly used in housing and household construction. As a rule, a cylindrical and simple structure, commonly known as a cork, is screwed into the base. Type D fuses have different rated currents and are marked with different colors.

The wide range of fuses is complemented by automatic fuses, gas-blow-out fuses and cylindrical fuse links. There are various types of fuse links on the market with different markings. Their proper selection has a direct impact on the correct operation of the electrical installation.

Time-current characteristics of fuses

The key parameter of fuses are the values ​​of the short-circuit currents they can carry. In order to select a fuse , it is worth paying attention to the rated short-circuit breaking capacity.

Different time-current characteristics correspond to different fuse-link values ​​depending on the requirements of the electrical circuit. They are responsible for the fuse's response time and inertia in the event of a short circuit. There are fast fuses marked as gF and delayed fuses marked as GL. An example of the first type fuse link is the ETI Polam 25A DII gF fuse link. Widely used in construction. An example of a time delay fuse is the DTII / E27 25A 500VAC fuse.

The most popular and recognized brands producing power line systems equipment and fuse links are: Hager Polo and ETI POLAM .