Cooper Bussmann FNQ-4/10 Time Delay Fuse 0.4A 500V

Product Description

The COOPER BUSSMANN FNQ-4/10 is a time delay cartridge fuse rated at 0.4 amps and 500 volts AC, with an interrupting capacity of 10 kA. The fuse body is constructed from fiber and features a cartridge form factor designed to seat in a standard fuse holder. It is used in low-current branch circuit and control circuit protection applications. The orange color coding aids in quick amperage identification during service calls. Electricians and maintenance technicians install this fuse type in industrial control panels, motor control circuits, and supplementary overcurrent protection applications where a time delay characteristic is required to ride through inrush events without nuisance tripping.

This fuse is suited for general-purpose overcurrent protection in residential, commercial, and light industrial control circuits. The time delay rating allows it to handle brief current surges common in motor starter and transformer circuits without opening prematurely. At 1-1/2 inches in overall length and 10.30 mm in diameter, it fits standard ferrule-style fuse holders sized for this footprint. It is commonly installed by licensed electricians working on low-voltage control wiring, HVAC equipment control circuits, and industrial machine panels where precise, low-amperage overcurrent protection is needed.

Key Features

• Time delay characteristic handles motor inrush and transformer surge without nuisance trips
• Rated 0.4 amps at 500 volts AC with 10 kA interrupting capacity
• Fiber cartridge body construction for reliable performance in fuse holder mounts
• Orange color body for fast visual amperage identification in the field
• CE Certified, CSA Certified, UL Listed 248-14, and RoHS Compliant

Compatibility

Designed for use in standard ferrule-style cartridge fuse holders that accept a 10.30 mm diameter, 1-1/2 inch length fuse body. Suitable for general-purpose supplementary and branch circuit protection applications where a 500V time delay fuse of this amperage rating is specified.

Installation Notes

Installation must be performed by a qualified electrician in accordance with NEC requirements for overcurrent protection devices. De-energize and lock out the circuit before removing or installing fuses. Use an insulated fuse puller appropriate for cartridge fuses when servicing live panels. Verify that the fuse holder is rated for the voltage and current of this fuse before installation.