The Siemens SENTRON 5SM1312-6 is a 2-pole residual current circuit breaker (RCCB) with a 25 A operational current rating and a 30 mA trip threshold, designed for 230 V AC, 50 Hz systems.
Key ratings and their meaning
The 25 A operational current matches common submain and feeder circuits; derating applies above 40 °C: at 50 °C it carries 24 A, at 60 °C 22 A, at 70 °C 20 A (–). The short-circuit current rating is 10 kA per the device's own rating, with a lower 0.5 kA limit when coordinated per EN 60898 or IEC 61008-1 — so on a high-fault panel, verify the upstream breaker's let-through stays within that coordination limit.
Snaps onto DIN rail (REG profile), occupies 2 modular width units — standard 18 mm per unit. Installation depth is 55 mm. Silicon-free construction matters for potting or coating processes where silicone contamination can cause adhesion failure.