Cooper Bussmann FNA-4 Cartridge Time Delay Fuse 4A 250V

Product Description

The COOPER BUSSMANN FNA-4 is a cartridge-style, time delay fuse rated at 4 amps and 250 volts. It features a dual-element design that tolerates brief inrush currents while still protecting circuits from sustained overloads and short circuits. The pin indicator provides a clear visual signal when the fuse has opened, allowing technicians to identify a blown fuse without removing it from the holder. At 0.01 pounds and 1.5 inches in overall length, the FNA-4 fits standard fuse holders used across HVAC control circuits, small appliance panels, and light industrial equipment.

The FNA-4 is suited for use in low-current control circuits where time delay protection is required. Common applications include HVAC equipment control boards, instrumentation panels, and light commercial electrical enclosures. The fuse mounts in a standard fuse holder and is appropriate for residential and light commercial installations where a compact, indicating, time delay fuse is specified. Its green color-coding aids quick identification during service calls.

Key Features

• Time delay dual-element design tolerates motor inrush and capacitive loads without nuisance opening
• Pin indicator provides visual blown-fuse confirmation without fuse removal
• 250-volt rating with 200-amp interrupting capacity at 250 volts and 10 kA interrupting rating at 125 volts
• Green color-coded body for fast visual identification in multi-fuse panels
• CE Certified, CSA Class 1422-01 Certified, and UL Listed for recognized installations
• Compact 1.5-inch overall length fits standard cartridge fuse holders

Compatibility

Designed as an OEM-style replacement for cartridge time delay fuses in standard fuse holders requiring a 4-amp, 250-volt, 1.5-inch cartridge fuse with pin indicator functionality.

Installation Notes

Installation should be performed by a licensed electrician or qualified HVAC technician. Always de-energize the circuit and verify voltage absence with a meter before replacing the fuse. The fuse mounts in a compatible cartridge fuse holder rated for 250 volts. Verify the replacement fuse amperage and voltage rating match the original equipment specification before energizing the circuit.