Schneider Electric A9N3P25DIN — an Acti9 xC60 miniature circuit breaker, 3-pole, D curve, rated 25 A. This is the one you grab when a motor circuit or transformer primary needs a high-inrush-tolerant thermal-magnetic trip. D-curve magnetic threshold kicks at 12 x In (±20 %), so it holds through the starting surge of a 25 A-rated motor or a 6 kVA transformer without nuisance tripping, then clears a hard fault at 10 kA Icn at 380–415 V AC (15 kA Icu at 100–125 V DC). Rated for category A utilisation per IS/IEC 60947-2, pollution degree 3, overvoltage category IV — meaning it's built for the main distribution board, not a clean-room sub-panel. IP20 finger-safe terminals; separate earth-leakage block available if you need it downstream. Electrical endurance rated 10,000 cycles, mechanical 20,000.
At 100–125 V DC the Icu climbs to 15 kA, which matters for battery banks or DC bus protection. The D curve means the magnetic trip won't fire until roughly 300 A instantaneous (12 x 25 A); compare that to a C curve (5–10 x In) that could trip on a motor start. If your load is resistive or a light inductive bank, you could oversize the breaker — stick with the 25 A rating for the conductor ampacity, not the load. Width is 54 mm (6 x 9 mm pitches) — standard 3-pole modular footprint. Depth 77.5 mm, height 85 mm. Fits any 35 mm DIN rail enclosure; leave clearance above for the toggle and below for the tunnel terminal wiring. Strip 13 mm for the conductor, torque to 2 N·m.
Current production part — no end-of-life notice, no successor. If you're filling a BOM line or replacing a failed unit on a live panel, this order code is still the active factory part.