Reliance Electric ECSR-80 Molded Case Circuit Breaker

Reliance Electric ECSR-80 is an 80-amp, 600-volt AC fuse cartridge in the RK5 family, now marketed under the Eaton Bussmann line as ECSR80, and it provides overcurrent protection for industrial power circuits within control panels, motor drives, and distribution gear. This time-delay, dual-element fuse—commonly described as Fusetron-style—tolerates brief inrush currents from motors and transformers while reliably interrupting faults, and it is designed for RK5-compatible fuse blocks and holders used in low- to mid-voltage industrial applications. With a 600 V rating and RK5 class designation, the ECSR-80 corresponds to the 80-A version within the ECSR family and should be selected only when the equipment’s continuous operating current does not exceed 80 A and the wiring and enclosure are rated for 600 V. The ECSR80 model label identifies the 80-Amp variant in the ECSR family; when selecting protection, ensure the current rating matches the equipment’s continuous operating current and that the wiring is rated for 600 V, and verify that the enclosure and mounting arrangement accommodate RK5-class fuses. As part of Eaton's Bussmann family, the ECSR-80 continues the legacy of Reliance Electric protection devices, offering compatibility with standard distribution gear and access to replacement parts through broad, global distributor networks.