The ABB 2CSR255188R1104 is a 2-pole residual current circuit breaker (RCBO) combining overcurrent and earth-leakage protection in a single DIN-rail module. Rated 10 A with a 30 mA fault-current trip threshold, it is sized for final subcircuits supplying socket outlets or small loads where both short-circuit and personnel protection are required. The 30 mA sensitivity is the standard threshold for supplementary protection against direct contact in residential and commercial installations (IEC 60364). The 500 V rated insulation voltage gives headroom on 400 V three-phase systems where phase-to-phase voltage appears across the device in a fault condition.
The 2-module width (35 mm) and 85 mm height fit standard enclosure cutouts; depth of 69 mm clears most 80 mm-deep enclosures.