The Siemens 5SM2725-6 is a SENTRON residual-current device (RCD) — a 2-pole, type A unit rated 63 A, 500 mA, 230 V AC, 50 Hz, designed as an instantaneous (non-delayed) RCD for use with 5SY miniature circuit breakers. Rated fault current is 500 mA.
Width is 71 mm, 2 modular width units. Depth is 70 mm, matching the 5SY breaker series it mates with, so the assembly sits flush in a 70 mm deep enclosure without protruding into the wiring gutter. Rated insulation voltage is 460 V; surge voltage resistance is 4 kV at overvoltage category III. Operating temperature range is -25 °C to 45 °C, with storage from -40 °C to 75 °C; pollution degree 2 (non-conductive pollution only) means it is suited for clean, dry indoor panels — not outdoor or condensing environments. IP20 protection applies only when the distribution board is installed with connected conductors — the RCD itself is not sealed against dust ingress, so it must live inside a closed enclosure.
Because it is an active, standard-catalog SENTRON part, it is sourced through normal Siemens distribution channels.