The Siemens 5SM3111-6 is a SENTRON residual current circuit breaker (RCCB) — 2-pole, 10 mA tripping threshold, Type A waveform detection, rated 16 A at 40 °C on a 230 V AC 50 Hz supply. Instantaneous trip, no intentional delay, so it clears ground faults on the first half-cycle. That 10 mA sensitivity catches leakage through electronics, variable-speed drives, and rectifier stages that a Type AC device would miss — common on modern mixed-load panels.
DIN-rail fit and thermal derating
Mounts on DIN rail (REG), 2 modular width units wide, 36 mm per unit. Depth is 70 mm — matches standard SENTRON RCCB profile, so it sits flush in a Siemens distribution board without protruding past the gland plate. Any mounting position allowed; supply line can enter top or bottom. IP20 with the distribution board installed and conductors connected — fine for enclosed panels, not for wet environments. Above that, derate linearly: 15.04 A at 50 °C, 14.08 A at 55 °C, 13.12 A at 60 °C, 12.16 A at 65 °C, 11.2 A at 70 °C. If the panel ambient hits 60 °C, the effective rating drops to 13.12 A — plan the load accordingly. Storage range is wider: -40 °C to 75 °C.
Breaking capacity and fault let-through
Surge current resistance 1 kA; permissible I²t is 70,000 A²·s. That let-through figure (7,500 kA — likely a data-entry unit mismatch for the rated conditional value) governs what the downstream wiring and devices see during a fault. Overvoltage category III, so it's rated for fixed-installation distribution panels, not plug-in portable gear.