The Siemens 5SM2325-0 is a 2-pole residual current device (RCD) from the SENTRON family, rated 63 A at 50 Hz with a 30 mA trip threshold, Type AC, instantaneous — no time delay, no adjustable fault current.
63 A at 40 °C (58.6 A) and derates to 50.4 A at 70 °C (–) — the thermal curve matters if your enclosure runs hot or you're packing modules tight. The 30 mA trip is the standard for personnel protection (shock hazard) in residential and light commercial; Type AC means it only detects sinusoidal AC residual currents, not pulsed DC or smooth DC — so if your load has rectifiers or VFDs, you need Type A or B instead. Instantaneous trip (no delay) means it will clear fast but can nuisance-trip on inrush from certain loads; if you have surge-sensitive gear, consider a selective (S-type) RCD. Insulation voltage rated 460 V, surge withstand 4 kV, overvoltage category III — solid for main distribution panels.
That's typical for indoor distribution gear — fine for most panel environments but not for freezers or outdoor cabinets without climate control. Mechanical life 10,000 operating cycles — adequate for a protection device that sees infrequent operation; if you're switching it weekly, it'll last decades. Pollution degree 2 — normal for a clean indoor panel. Not sealable — no padlock hasp for lockout/tagout on the RCD itself; you'd need a separate disconnect.