The Siemens 5SU1354-7LB10 is a SENTRON RCBO — a combined residual-current and overcurrent protective device in a single 2-module-width (36 mm) package, 1P+N pole configuration with one protected pole. It is designed for final circuits in distribution boards where both earth-leakage and short-circuit/overload protection are required in one unit, saving a DIN-rail position compared to separate RCCB and MCB. The design is marked "Short-time delayed G, super resistant K" — the residual-current element is a G-type (short-time delayed, typically 10 ms minimum non-tripping time) to avoid nuisance tripping from transient leakage pulses common on electronic loads, and the K suffix indicates enhanced immunity to surge currents (lightning or switching surges) without false operation.
The 10 A rating is only valid at 30 °C ambient inside the distribution board. Per the datasheet derating table, at 40 °C the continuous current drops to 9.5 A, at 50 °C to 9 A, at 60 °C to 8.5 A, and at 70 °C to 7.7 A. If your panel runs warm — common in crowded enclosures or near transformers — size the upstream protection and the connected load against the derated figure, not the 30 °C nameplate.