Siemens 5SM3312-6KK04 SENTRON RCCB — 2-pole Type A, 25 A, 30 mA, 130 V AC
It carries a 25 A rated current and a 30 mA rated residual trip current at 130 V AC — the pairing that defines its fit: 25 A for the load circuit, 30 mA for personnel protection against direct contact. The Type A design detects pulsating DC fault currents on top of sinusoidal AC, so it covers rectifier-fed loads (switched-mode supplies, variable-speed drives) that a plain AC-sensitive RCCB would miss. Mounts on DIN rail, occupies 2 width units, and accepts conductors from 1 to 16 mm² solid or stranded. Terminal torque spec is 2.5 to 3 N·m. Overvoltage category III (permanent connection to the building installation). Protection class IP20 with connected conductors in an installed distribution board.
Where this RCCB fits in the panel
This is a DIN-rail mounted RCCB (2-pole, 2 width units) for distribution boards and sub-distribution panels. Installation depth is 70 mm. Mounting position is any orientation. Power supply connection can be top or bottom, which simplifies busbar routing in crowded enclosures. The housing is finger and back-of-hand touch-safe per the shock-protection classification. Silicon-free construction is relevant for applications where silicone outgassing can contaminate contacts or optical surfaces — automotive paint shops, electronics assembly, or cleanroom-adjacent panels.