What this RCCB carries
The Siemens 5SV3442-6MJ01 is a residual current operated circuit breaker Type A, rated 25 A with a 100 mA trip sensitivity, 3+N-pole configuration at 400 V, and a 10 kA breaking capacity. The short-time-delayed G characteristic means it tolerates brief surge currents (like those from connected electronics or motor inrush) without nuisance tripping, while still clearing a genuine ground fault within the delayed window. That delay is key for selectivity in a sub-distribution panel — you want the downstream RCCB to trip first, not the upstream main switch.
Where it fits in the panel
Mounts on standard DIN rail in a distribution or sub-distribution board. The 3+N-pole format (switched neutral) suits TN-S or TN-C-S systems where the neutral must be disconnected with the phases. The G characteristic (short-time-delayed) lets it coordinate with downstream 10 mA or 30 mA RCCBs in medical or wet-area sub-circuits — the delayed upstream unit stays in while the faster downstream clears the fault.