The Siemens 5SM2746-8 is a 4-pole residual current unit (RC unit), type A, rated 63 A continuous current with a 500 mA residual operating current, for use on 400 V AC systems. It's designed as a selective (time-delayed) device to coordinate with the 5SL series of miniature circuit breakers — meaning it sits upstream and lets downstream short-circuit protection clear first before tripping on a ground fault. That selectivity is key in a distribution board where you don't want the main RCD dumping the whole panel for a fault on one branch.
RoHS compliant since 30 June 2025, and REACH Article 33 duty-to-inform data is available on the current candidate list. No export restrictions (AL: N / ECCN: N). The packaging dimensions are 130 x 105 x 81 mm, shipped as a single piece.