The Siemens 5SU1353-1WM25 is a SENTRON RCBO (residual current circuit breaker with overcurrent protection) in a 1P+N configuration, rated 25 A with a C tripping characteristic and 30 mA AC-type residual current detection. It breaks faults at 4.5 kA per EN 60898 and 15 kA per IEC 60947-2, giving you two ratings to match the applicable standard for the panel design. The 30 mA sensitivity covers personnel protection against line-to-ground faults on AC circuits, while the C curve handles moderate inrush from motorized or fluorescent loads without nuisance tripping.
Panel fit and wiring
Occupies 2 width units (about 36 mm on a DIN rail) with a 70 mm installation depth — fits standard SENTRON distribution boards and most 18 mm-pitch enclosures. Solid or stranded conductors from 0.75 to 35 mm² are accepted under the screw terminals; tighten to 2.5–3 N·m. Supply can enter from top or bottom, and the neutral is switched internally (no external link needed). Mount in any position; ambient range is -25 to +55 °C, storage -40 to +75 °C.
Key ratings at a glance
Power dissipation maxes at 10.2 W under full load — factor that into enclosure thermal calculations, especially in a densely populated board. Mechanical endurance is 10 000 switching cycles typical. Surge current withstand is 1 kA (8/20 μs waveform). Overvoltage category III, energy limiting class 3. Halogen-free and silicon-free construction. Touch protection is built in. IP20 rating applies once installed in a distribution board with conductors connected.