The Siemens 5SM3616-6 is a 2-pole residual-current circuit breaker (RCCB) from the SENTRON 5SM3 series, rated 63 A at 40 °C and 230 V AC, 50 Hz.
The 63 A rating holds at 40 °C and 45 °C; above that it derates linearly to 50.4 A at 70 °C. If your panel ambient runs hot — say, 55 °C inside a sealed enclosure — you are looking at 57.96 A continuous, so a 63 A breaker on a 60 A load is tight. The solid and stranded conductor range is 1.5 to 25 mm², which covers standard branch-circuit wiring up to 6 AWG copper. The 2-pole design switches both phase and neutral on a single-phase 230 V AC supply. Type A fault-current detection handles sinusoidal AC and pulsating DC — important for circuits with rectifiers, switching power supplies, or VFDs that generate DC ripple. The instantaneous (non-time-delayed) trip characteristic means it responds to any earth fault above its rated residual current without intentional delay, so it is best used where nuisance tripping from transient leakage (e.g., motor starting or capacitor inrush) is not expected.
Mounts on DIN rail (REG), occupies 2.5 width units (about 45 mm of rail space). Depth is 70 mm, height 90 mm, width 36 mm. Installation depth matches the 70 mm dimension — factor that into enclosure depth if you are retrofitting into a shallow gland plate or a compact distribution board. Rated IP20 with conductors connected and the distribution board installed, so it is intended for enclosed panel use, not open washdown areas. The silicon-free feature matters for potting or conformal-coating processes in automotive or aerospace panels.