The Schneider Electric A9N4P25CIN is a 4-pole miniature circuit-breaker from the Acti9 xC60 range, rated 25 A with a C curve. Breaking capacity is 10 kA at 380–415 V AC (IS/IEC 60947-2) and 6 kA at 220–250 V DC.
For a distribution board feeding socket circuits or general lighting, 25 A is a common final-circuit rating. The C curve gives a magnetic trip threshold of 8 x In ±20 %, so the breaker holds through inrush from a few fluorescent ballasts or a small motor start but trips fast on a hard short. The 4-pole configuration switches all phases and neutral, required for three-phase distribution where the neutral must be disconnected for isolation.
Integration notes for the panel builder
Tightening torque 2 N.m. The white housing with ON/OFF toggle indication gives clear visual status. Earth-leakage protection is handled by a separate block, so if RCD protection is needed, pair it with a compatible Acti9 Vigi module. The 77.5 mm depth fits standard distribution board depths; no overhang issues on a 100 mm deep enclosure.