Compared to the 5SU9354-7KK16 (an RCBO with 1P+N, 10 kA EN 60898, 230/240 V AC), the 5SN6203-7CP is a straight MCB — no residual-current protection, but it handles 400 V AC and delivers 30 kA under IEC 60947-2 versus the RCBO's 10 kA. If the panel needs a 2-pole breaker on a 400 V line with higher fault capacity and no RCD function, the 5SN6203-7CP is the fit; if you need combined overcurrent and earth-leakage protection on a single-phase circuit, the 5SU9354-7KK16 is the RCBO. Different jobs, same DIN-rail footprint and 2 MWU width.
Accepts solid conductors up to 35 mm² — enough for the load side of a 2-pole 400 V feeder.
The 440 V AC maximum with multi-phase or single-phase operation covers nominal 400 V systems plus tolerance. For DC circuits, the 72 V maximum is the limit; above that, use a DC-rated breaker.