The Siemens 5SU9354-8KK06 is a SENTRON RCBO — a combined RCD and MCB in one 2-module-width unit, rated 6 A with a D tripping characteristic and 30 mA Type A residual current protection. It breaks fault currents up to 10 kA per EN 60898 and IEC 60947-2, which covers most residential and light commercial distribution boards. The D curve means it tolerates high inrush currents (motor starts, transformer energisation) without nuisance tripping — the magnetic release kicks in at 10–20× rated current, so it's a fit for circuits with inductive loads where a B or C curve would trip on startup.
Derating and mounting
Rated 6 A at 30 °C, but the continuous current drops to 5.64 A at 40 °C and 4.86 A at 55 °C — factor that into your load calculation if the panel runs warm. Mounts in any position, supply from top or bottom, and the 77 mm depth plus 70 mm installation depth fits standard DIN-rail enclosures. IP20 with conductors connected, so it's enclosed-panel only; not for wet or outdoor locations.