The Siemens 5SV3447-6MJ01 is a residual current operated circuit breaker (RCCB) — Type A, rated 80 A at 400 V with a 100 mA trip sensitivity and a 10 kA breaking capacity. The 3+N-pole configuration and short-time delayed characteristic make it suited for circuits where nuisance tripping from transient surges or inrush currents needs to be avoided, such as feeder circuits with downstream switching loads.
The 3+N-pole format occupies four module widths on a DIN rail, standard for panel integration in distribution boards or sub-distribution enclosures. The short-time delayed characteristic (typically 10 ms or similar) coordinates with downstream MCBs to provide selectivity — the RCCB holds during a fault on a branch circuit, letting the branch breaker clear it first.