It protects a 3P+N outgoing circuit against both overload/short-circuit and ground faults, all in one DIN-rail mounted unit. The C-curve (magnetic trip at 5 to 10 x In) means it tolerates moderate inrush from motor or lighting loads without nuisance tripping, while the 300 mA sensitivity is sized for general distribution rather than personnel protection — think submain or equipment protection where a 30 mA RCD would be too sensitive.
The 3P+N unit occupies 10 x 9 mm pitches — 90 mm width total. Neutral is on the left. Tunnel-type terminals accept 0.75…16 mm² rigid or 0.33…10 mm² flexible; tighten to 2 N·m. IP20 on the front, IP40 inside the modular enclosure.
Durability and compliance
Rated for 20,000 electrical and 20,000 mechanical cycles. Complies with EN/IEC 61009-2-1 for combined RCBO performance. Limitation class 3 (energy-limiting) helps with downstream selectivity. Local signalling shows ON, OFF, and fault-trip status on the toggle.