The Siemens SENTRON 5SM2647-8 is a 4-pole selective residual-current device (RCD) built for 100 A AC circuits at 50/60 Hz. The selective design (Type S) means it withstands short-duration earth faults without tripping, so only the downstream RCD clears a ground leak on a branch. That keeps the rest of the distribution board live during a fault on one circuit. Rated fault current is 300 mA Type A, covering sinusoidal AC and pulsed DC residual currents up to that threshold. Width is 5 modular units, depth 70 mm. IP20 with the distribution board enclosed.
Derating curve — the number that actually governs your panel
The 100 A rating holds only up to 40 °C. At 45 °C it's 93 A, at 50 °C it's 90 A, at 60 °C it's 85 A, and at 70 °C it's 80 A. If your panel runs warm — say 55 °C near the top of a sealed enclosure — you're limited to 87 A continuous. Plan the upstream breaker and conductor accordingly. Surge current withstand is 5 kA, surge voltage 4 kV, overvoltage category III. Insulation voltage rated 460 V. Pollution degree 2 — normal indoor environment, no conductive dust or condensation.