The WATSNB-630/630 .4CBR is a compact, modular 4-pole circuit breaker from Schneider Electric's Acti 9 series. It combines the functions of a miniature circuit breaker (MCB) for overload and short-circuit protection with advanced residual current protection using Current Balance Relay (CBR) technology. This device is specifically designed for applications requiring high immunity to nuisance tripping while providing protection against various types of residual currents, including smooth DC components.