What this RCCB is and where it fits
The Siemens 5SV4347-0KL is a 4-pole residual current circuit breaker (RCCB) from the SENTRON family, designed for AC systems. It is rated 80 A at 400 V AC, 50 Hz only, with a 30 mA residual operating current — Type AC, meaning it detects sinusoidal AC fault currents only. The short-circuit current rating is 10 kA per IEC 61008-1, with a conditional rated short-circuit current of 0.8 kA. This is an instantaneous-trip device (no short-time delay), so it responds immediately to ground faults. It occupies 4 modular width units (72 mm wide) on a DIN rail, and the supply can enter from top or bottom. The N pole is on the left side of the device.
Panel integration and mounting
Mounts on a standard DIN rail (REG) in any position. The 4-pole, 4-MW footprint (72 mm wide, 90 mm tall, 70 mm deep) fits a standard 60 mm grid distribution board. Installation depth is 70 mm. The IP20 rating applies only when the distribution board is installed with conductors connected — this is an enclosed-panel device, not for standalone outdoor use. Ambient operating range is -25 °C to 45 °C; storage range extends to -40 °C. Supplementary devices (e.g., auxiliary switches, shunt trips) can be installed on the right side. The housing is silicon-free, important for applications where silicone outgassing can contaminate contacts or optics.
Key ratings and what they mean for selection
The 80 A continuous rating at 40 °C ambient is the thermal limit for the main circuit — size upstream protection accordingly. The 30 mA residual sensitivity is the standard for personnel protection (shock) in most residential and commercial codes; it will trip on leakage currents above that threshold. The 10 kA SCCR means the device can safely interrupt fault currents up to 10 kA without external fusing, but a series fuse rated up to 100 A is permissible if the available fault current exceeds that. Power dissipation is 4.1 W per pole at rated current — total 16.4 W for the 4-pole unit, which matters for thermal management in a crowded enclosure. Mechanical life is 10,000 operating cycles typical.