The Siemens 5SV3347-4KK14 is a SENTRON residual-current circuit breaker (RCCB) with a Type B+ characteristic, rated 80 A at 40 °C through 50 °C, and a 30 mA trip threshold. The Type B+ designation means it detects AC, pulsating DC, smooth DC, and high-frequency AC residual currents — the full spectrum you get from modern VFDs, UPS systems, and EV charging stations. The short-time delayed switching function prevents nuisance tripping from transient surge currents up to 3 kA, and the let-through current is capped at 7 000 A.
Thermal derating — the real-world current you can actually run
Above that, it steps down: 72 A at 55 °C, 64 A at 60 °C, 56 A at 65 °C, and 48 A at 70 °C (–). If your panel ambient runs at 60 °C, you're limited to 64 A continuous — the full 80 A is only available in cooler environments. The maximum permissible ambient is 75 °C, storage range goes to -40 °C.
Mounting and integration — DIN rail, any orientation
Depth is 70 mm, height 90 mm. Mounting position is any — no restriction on upright or sideways. Supply connection can be top or bottom; the SIGRES function stays active even in the switched-off state when fed from the top. IP20 rating applies only when the distribution board is installed with connected conductors — not a standalone outdoor part.