What the ratings mean for your panel
The 5SM3446-6LA: The 63 A rated current and 100 mA residual trip make this RCCB a fit for sub-distribution boards feeding mixed loads — lighting, small motors, and general socket circuits — where a 30 mA trip would cause nuisance tripping from leakage in long cable runs or equipment with inherent earth leakage. Type A detection covers pulsating DC fault currents (common in single-phase rectifier loads like VFDs and switching power supplies) in addition to sinusoidal AC faults. The 10 kA SCCR at 400 V AC means the device can safely interrupt a bolted fault up to that level without rupturing or cascading upstream — coordination with a 10 kA or higher MCB or fuse on the supply side is straightforward. Overvoltage category III confirms it is rated for fixed-installation distribution panels, not just downstream equipment. Mounts on a DIN rail (REG profile), occupies 4 width units (about 72 mm), and accepts solid or stranded conductors from 1.5 to 25 mm². The screw terminals call for 2.5 to 3 N·m torque. IP20 with conductors connected — standard for enclosed distribution boards; not for wet or washdown locations.