FNQ-R-15

Specialty Fuses: FNQ-R-15 Application Field and Working Principle

A specialty fuse is a specific type of fuse designed to protect a more valuable electrical or electronic component from over current or thermal conditions. FNQ-R-15 fuses are thermal-magnetic trip class C, time-delay fuses for commercial and industrial applications. The maximum operating current for FNQ-R-15 is 15 ampere at maximum 600/480V. This fuse is rated for intermittent operation up to 20,000A.

Application Field

FNQ-R-15 fuses are particularly suitable for applications such as motor control centers, automotive switchgear, air-conditioning systems, power distribution panels, industrial control panels, and uninterruptible power supplies. They are designed to protect lighting fixtures, motors, small transformers, power supplies, and other circuit components from current surges or overloads.

Working Principle

FNQ-R-15 fuses are designed to manage two separate situations, one is overload and the other is short circuit. The overload current trip element is designed to detect over-current conditions and trip to interrupt the power when the current value rises above the appropriate ampere value. When the current exceeds the tripsetting, the internal element uses the heat generated by the current flow and melts the bimetallic spring, which breaks the circuit and opens the fuse.

In the case of short circuit conditions, the trip element is designed to detect excessive current levels and to immediately trip to interrupt the power when the current value rises above the trip settings. This is achieved through the use of a magnetic operating principle. When current flows through the fuse, the magnetic field produced by the flowing current will attract a shutter which will close over the fuse. This will interfere with the current, cause the fuse to trip, and open the circuit.

FNQ-R-15 fuses provide a significant amount of protection and flexibility for commercial and industrial applications. They are designed to be both economically priced and efficient in operation.