RCD-unit for 63 A feeder circuits
The Siemens 5SM2425-6 is a 2-pole SENTRON residual current device (RCD-unit) rated 63 A at AC, with a 100 mA trip threshold and Type A waveform sensitivity. Instantaneous design — no adjustable delay — so it trips within the cycle on a ground fault. The 100 mA rating suits sub-distribution or equipment-level protection where 30 mA would nuisance-trip on leakage, but you still need personnel protection for wet or portable loads.
What the ratings mean for your panel
Type A detection covers sinusoidal AC residual currents plus pulsating DC. The 63 A AC rating is the thermal continuous current at 40 °C ambient; derate to 58.6 A at 40 °C, 56.7 A at 50 °C, and 50.4 A at 70 °C.