Cooper Bussmann FWH-70B High-Speed Semiconductor Fuse

The Bussmann FWH-70B is a high-speed semiconductor fuse from Bussmann (Eaton) that provides fast-acting overcurrent protection for power electronics in industrial equipment. Rated 70 A with a maximum of 500 VAC / 500 VDC, it uses the aR fuse class for semiconductor protection, an interrupt rating of 200 kA (AC), and a center-bolted (blade-end) bolt-mount ceramic body designed for rugged industrial power conversion applications. This fuse is used in variable frequency drives, DC drives, UPS systems, rectifiers, inverters, and other industrial automation gear to limit fault energy and protect SCRs, diodes, and IGBTs from short circuits or overloads. Common replacements include Eaton Bussmann FWH-70BC, Mersen A70QS70, and Littelfuse L70S070 when electrically compatible.