The Siemens 5SM1347-6 is a SENTRON series residual current circuit breaker (RCCB) designed for 4-pole, 400 V AC systems. It carries an 80 A rated current and a 30 mA residual trip threshold, Type A waveform detection — meaning it catches pulsating DC fault currents as well as standard AC, which is the typical requirement for circuits feeding single-phase rectified loads like switched-mode power supplies or variable-speed drives. Rated short-circuit current withstand is 10 kA, and the unit is instantaneous (no short-time delay), so it trips immediately on residual fault — standard for personnel protection in final subcircuits. The 30 mA trip level is the common threshold for shock protection in residential and light commercial panels.
Mounts on DIN rail (REG profile), occupies 4 width units (approx 72 mm). Installation depth is 55 mm. The housing is IP20 once installed in a distribution board with conductors connected — so it's intended for enclosed panel use, not open or wet locations. Ambient temperature range is -25 to +45 °C, with storage from -40 to +60 °C. Any mounting position is permitted. Terminals accept solid or stranded conductors from 1.5 to 25 mm². Tightening torque is 2.5 to 3 N·m with screw-type terminals. Supply connection can be top or bottom — no polarity restriction on this RCCB design.
Mechanical service life is 10 000 switching cycles typical. The unit is silicone-free, which matters for applications where silicone outgassing can contaminate contacts or optical surfaces. Overvoltage category III, pollution degree typical for distribution boards. The design family is 5SM1.