What the ratings mean for your panel
The Siemens 5SP4363-7 is a 3-pole SENTRON miniature circuit breaker from the 5SP4 series, rated 63 A at 400 V AC with a C tripping characteristic. The C-curve means it trips between 5 and 10 times rated current — standard for motor and lighting circuits where inrush is moderate, not for pure resistive loads where a B-curve would suffice, nor for high-inrush transformers where a D-curve is needed. The 10 kA breaking capacity per EN 60898 covers most residential and light commercial distribution boards; the 20 kA rating per IEC 60947-2 applies when the breaker is installed in an industrial enclosure with higher prospective fault current — that 20 kA figure is the one to use for SCCR coordination studies on a machine panel. Pollution degree 3 means the breaker is rated for conductive pollution or dry non-conductive pollution that becomes conductive due to condensation — typical for control panels in factory environments, not for sealed or climate-controlled cabinets. The 70 mm installation depth is standard for DIN-rail mount enclosures; tunnel terminals top and bottom accept copper conductors without lug adapters, which saves wiring time on a distribution board.