Siemens SENTRON 5SM2647-0 RCD unit, 4-pole, 100 A, 300 mA
The Siemens SENTRON 5SM2647-0 is a 4-pole residual current device (RCD) of type AC, rated for 100 A continuous current and 300 mA fault sensitivity at 400 V AC, 50 Hz. It's designed as an instantaneous-trip unit — no adjustable time delay — so it responds immediately to earth leakage above the threshold, which is the standard choice for general-purpose shock protection in distribution boards where selectivity with downstream RCDs isn't required. This RCD mounts in a SENTRON distribution board, occupying 5 modular width units (roughly 90 mm of DIN-rail space). The housing is IP20 with conductors connected, meaning it's protected against finger contact but not against moisture — standard for enclosed panel installation.
Sourcing and lifecycle — active, quoted to order
The part belongs to the SENTRON family of protection devices, used across residential, commercial, and industrial distribution. No official successor or replacement has been published; the 5SM2647-0 remains the current order code for a 4-pole 100 A/300 mA Type AC RCD in the 5SP4 system.