Siemens 5SU1354-0KK10 — SENTRON RCBO, Type B, 10 A
The breaking capacity is rated 10 kA according to EN 60898 and 20 kA according to IEC 60947-2, giving the buyer flexibility depending on the applicable standard at the installation site. The higher IEC rating covers industrial panel applications where prospective fault currents may exceed the domestic standard's limit. Operating frequency is fixed at 50 Hz; the unit is designed for 230/240 V AC supply.
Thermal derating and installation constraints
The 5SU1354-0KK10 carries a published derating curve: 10 A at 30 °C ambient, stepping down to 9.5 A at 40 °C, 9.3 A at 45 °C, 9 A at 50 °C, 8.7 A at 55 °C, 8.5 A at 60 °C, 8.2 A at 65 °C, and 8 A at 70 °C. In a crowded DIN-rail enclosure with multiple RCBOs side-by-side, the effective rating at typical 40–50 °C internal ambient is what governs the circuit design — not the 30 °C nameplate number. The IP20 rating applies once the distribution board is installed with connected conductors — the device itself is not rated for exposed or wet locations. Supply connection can be made from either the top or bottom, and the unit is halogen-free and silicon-free — relevant for environments with strict material restrictions (e.g., rail, marine, or cleanroom adjacent panels).