Bussmann FRS-R125 Fusetron RK5 Time Delay Fuse

FRS-R125 Fusetron RK5 Time-Delay Fuse from Bussmann (Eaton) is a UL Class RK5 dual-element, current-limiting cartridge fuse designed for circuit protection up to 600 VAC / 300 VDC. It is rated 125 A, non-indicating, with an interrupting rating of 200 kA at 600 VAC and 20 kA at 300 VDC, aligning with industrial protection standards for power distribution and control circuits. As part of the FRS-R family, it offers energy-efficient protection through a time-delay (dual-element) design that tolerates brief overloads without nuisance blows while safeguarding downstream equipment. The RK5 family is a common protection option for equipment in industrial and commercial power systems, and this 125 A rating fits higher-current applications requiring robust fault isolation while remaining compatible with standard RK5 fuse holders. Optional open-fuse indication is available on select ratings, though this particular model is listed as non-indicating.