Cooper Bussmann FRN-R-8 RK5 Time Delay Fuse 8A

Product Description

The COOPER BUSSMANN FRN-R-8 is a Class RK5 cartridge time delay fuse rated at 8 amps, designed for general-purpose overcurrent protection in commercial and industrial electrical systems. The dual-element, time delay construction allows the fuse to withstand temporary inrush currents — such as those produced by motor starts — without nuisance opening, while still providing reliable short-circuit protection. At 2 inches overall length and 14.3 mm diameter, it installs into standard Class RK5 fuse holders. Licensed electricians and industrial maintenance technicians are the primary installers of this component.

This fuse is suited for use in motor branch circuits, control panel feeder circuits, and equipment requiring time delay overcurrent protection. The RK5 class rating makes it compatible with dual-element fuse holders commonly found in disconnect switches, motor control centers, and distribution panels in residential, commercial, and light industrial applications. Its non-indicating design provides no visible blown indication, so circuit testing is required during troubleshooting to confirm fuse status.

Key Features

• Class RK5 dual-element time delay construction tolerates motor inrush without nuisance opening
• 8-amp rating for precise overcurrent protection in low-amperage branch circuits
• Non-indicating body — no external blown indicator
• Cartridge body mounts in standard Class RK5 fuse holders
• CE Certified, CSA C22.2 No. 248.12 Certified, and UL Listed 248-12 Class RK5
• 20 kA interrupting rating at DC 200 RMS for high fault-current environments

Compatibility

Designed as an OEM-style replacement for Class RK5 cartridge fuse applications requiring an 8-amp time delay fuse in a standard 2-inch cartridge form factor.

Installation Notes

Installation should be performed by a licensed electrician in accordance with NEC requirements for overcurrent protection devices. De-energize and lock out the circuit before removing or installing any fuse. Confirm the fuse holder is rated for Class RK5 cartridge fuses before installation. Do not substitute a higher-amperage fuse or a different fuse class in place of this component.