Bussmann 170M4109 High Speed Square Body Fuse

The Bussmann (Eaton) 170M4109 High-Speed Square-Body Fuse is a 250 A, 690/700 V fast-acting protection device in the Bussmann 170M series. Classified as an AR-class, square-body fuse, it delivers a 200 kA interrupting rating and is designed for semiconductor power circuits and power electronics where rapid fault clearance is required. The 170M family is documented as covering currents from 40 A up to 2000 A, with 170M4109 representing the 250 A variant specified for 690 VAC / 700 V DC applications. This model is intended for use with standard square-body fuse holders in industrial equipment, inverter drives, and high-energy electronic systems that require swift fault interruption at the 250 A level to protect downstream devices. Manufactured under the Bussmann brand by Eaton, the 170M4109 exemplifies Eaton’s high-speed, square-body fuse line designed to provide fast, predictable protection in demanding electrical installations.