What this RCBO does on the panel
The Schneider Electric A9D55725 is a 25 A RCBO from the Acti9 DPN Vigi range — a combined overcurrent and earth-leakage protector in a single modular package. It is a 3-pole + neutral device (3P+N) with the neutral on the left, rated for AC networks at 50/60 Hz. The integrated 30 mA earth-leakage sensitivity covers personnel protection and fire-risk reduction on outgoing circuits.
Trip curve and coordination
The B-curve on this RCBO (3–5 x In) gives a faster magnetic trip than a C-curve (5–10 x In) but slower than a D-curve (10–20 x In). For a 25 A circuit, the instantaneous trip threshold sits between 75 A and 125 A. That makes it a good fit for resistive loads, lighting circuits, and small motor loads with low starting surge. If your BOM calls for a C-curve — typical for moderate inrush like small transformers or contactor coils — this unit won't delay enough to avoid nuisance trips. The limitation class is 3 per EN/IEC 61009-2-1, meaning it limits let-through energy to a defined level during a fault, which helps with downstream device coordination.
The tunnel-type terminals accept rigid cable up to 16 mm² or flexible up to 10 mm². The connection pitch is 18 mm between phases and 9 mm between phase and neutral — that matches standard busbar spacing for Acti9 modular enclosures. IP20 rated per IEC 60529 on the terminals, IP40 on the modular enclosure body — so it is protected against tools and wires >12.5 mm, but not against water ingress. Keep it inside the panel enclosure. The toggle provides ON, OFF, and fault-trip local signalling.
Durability and environmental tolerance
Rated for 10,000 electrical cycles and 20,000 mechanical cycles. That is typical for a distribution RCBO — not designed for frequent switching duty like a contactor, but adequate for normal breaker operation. Relative humidity tolerance is 90% at 55 °C. Operating temperature range is implied by the tropicalisation class and the overvoltage category; no explicit min/max temperatures are listed in the spec record.