The Siemens SENTRON 5SM3344-0LA01 is a 2-pole residual current circuit breaker (RCCB) with thermal overload protection, rated 40 A at 230 V AC and 30 mA trip sensitivity, type AC, short-time delayed. The 10 kA short-circuit current rating (SCCR) and 3 kA surge current resistance mean it holds up under fault conditions common in residential and light commercial mains, not just nuisance trips.
The short-time delayed characteristic means it tolerates brief inrush or surge currents (like from motor starts or capacitor banks) without tripping, while still clearing a genuine ground fault. That makes it a better fit for circuits with electronic loads or drives than a standard instantaneous RCCB. The 40 A rated current and 230 V AC supply match a typical single-phase submain or feeder in European-style panels.
Panel integration
Tightening torque is 2.5 to 3 N·m. The IP20 rating applies once the distribution board is installed with conductors connected — it is not a standalone outdoor device.