1SYF274027R1404

The ABB DSB204M AC-C40/30mA, part number 1SYF274027R1404, is a four-pole residual current circuit breaker with overcurrent protection (RCBO) designed to protect compatible low-voltage electrical installations against overloads, short circuits and earth-leakage faults.

The device has a rated current of 40 A, a C-type tripping characteristic and a rated residual operating current of 30 mA (0.03 A). It uses Type AC residual-current detection and is designed for compatible three-phase, four-wire electrical systems, including neutral switching. Its eight-module construction supports DIN-rail installation in electrical distribution boards and control panels.

The RCBO combines overcurrent protection and residual-current detection in one device. Its 30 mA sensitivity provides additional protection against electric shock when correctly selected and installed. It is suitable for residential, commercial and industrial installations where the rated current, cable capacity and fault-current conditions meet the applicable requirements. Installation should follow ABB's technical documentation and local electrical standards.