Bussmann FRS-R-400 Fusetron Dual Element Fuse

The Bussmann FRS-R-400 Fusetron Dual-Element fuse is a 600 V, time-delay, dual‑element current‑limiting device in the RK5 class engineered for high‑current protection in industrial electrical systems. It is rated for 400 A and delivers an impressive interrupting rating of 200 kA at 600 VAC and 20 kA at 300 VDC, making it suitable for heavy loads such as motor drives and power-distribution circuits that experience brief surge currents. This energy‑efficient Fusetron part (FRS-R) is a non‑indicating fuse with dual elements designed to tolerate short overloads while swiftly interrupting faults to protect downstream equipment. The fuse body is fiberglass and measures about 2.34 inches in diameter by 11.63 inches in length, and it uses knife‑blade terminals with holder‑mount compatibility for straightforward panel installations. In practice, the FRS-R‑400 combines reliable time‑delay protection with robust current limiting, helping crews guard electric drives, feeders, and distribution panels against both sustained overloads and transient startup currents without sacrificing fast fault interruption.