The Siemens SENTRON 5SV5312-6KL is a 2-pole residual current circuit breaker (RCCB), type A, rated at 25 A with a 30 mA trip threshold for 230 V AC circuits. It's an instantaneous-trip device — no intentional time delay — so it clears ground faults as fast as the fault waveform allows.
The neutral comes on the left side (N left), which lines up with the busbar arrangement in most European-style distribution boards. Feed from top or bottom; mounting orientation in any position is fine. The IP20 rating applies only after the distribution board is installed and conductors are connected — not a standalone enclosure rating.
Short-circuit withstand is rated at 6 kA per IEC 61008-1, with a let-through current of 5 200 A and an I²t of 58 000 A²s. That 6 kA SCCR is typical for final-subcircuit protection in a domestic or light-commercial panel where the upstream breaker limits fault energy. The surge-current resistance is rated at 1 kA (8/20 µs waveform), and the device also passes the 0.5 kA test per IEC 61008-1 — meaning it won't nuisance-trip from a lightning surge or capacitor inrush on the line side. Operating frequency is fixed at 50 Hz.