Cooper Bussmann FNQ-3 Cartridge Time Delay Fuse 3A 500V

Product Description

The COOPER BUSSMANN FNQ-3 is a cartridge-style, time-delay fuse rated at 3 amps and 500 volts AC with a 10 kA interrupting capacity. Built with a fiber fuse body, it is sized at 1.5 inches in length and 0.406 inches in diameter, fitting standard fuse holders used across HVAC control circuits, motor branch circuits, and general-purpose electrical panels. Electricians and HVAC technicians install this fuse to provide overcurrent protection where a brief inrush current must be tolerated before the fuse acts. The time-delay characteristic prevents nuisance trips on motor starts while still protecting downstream components from sustained fault current.

This fuse is suited for residential and light commercial applications wherever a 3-amp time-delay cartridge fuse is called for in a fuse holder mount. Typical uses include transformer secondary protection, low-voltage control circuit protection in HVAC systems, and supplemental protection in industrial control panels. The orange color coding aids in quick amperage identification during service calls. Its compact cartridge form and standard dimensions make it a direct fit in most midget fuse holders designed for this class of fuse.

Key Features

• Time-delay action tolerates motor inrush current while protecting against sustained overcurrent
• Rated 500 volts AC with 10 kA interrupting capacity at AC
• Fiber fuse body construction for reliable performance in standard fuse holders
• Orange color coding for quick visual amperage identification in the field
• Meets CE, CSA, UL, and RoHS requirements for broad application compliance

Compatibility

Designed as an OEM-style replacement cartridge time-delay fuse for use in standard midget fuse holders accepting a 1.5-inch cartridge fuse body.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the NEC and applicable local codes. Always de-energize and lock out the circuit before removing or replacing fuses. Use an approved fuse puller when extracting cartridge fuses from live-rated holders to avoid contact with energized components. Verify that the replacement fuse amperage and voltage rating match the circuit requirements before restoring power.