Acti9 xC60 4 A D-curve MCB — what fits and what it clears
The Schneider Electric A9N3P04DGN is a 3-pole miniature circuit breaker from the Acti9 xC60 series, rated at 4 A with a D tripping curve. Breaking capacity is 10,000 A Icn at both 240 V and 415 V AC, certified to IS/IEC 60898-1.
Trip curve and selectivity — why D curve matters here
The D curve (magnetic trip 10–14 × In) is the key differentiator. At 4 A, that's a magnetic trip window of 40 to 56 A instantaneous. The thermal-magnetic trip unit handles the overload side; the magnetic coil handles the short-circuit side. Limitation class 3 per IS/IEC 60898-1 means this breaker limits the let-through energy under short-circuit conditions, which helps with downstream coordination.
Mounting and integration — DIN-rail clip, 6-pitch wide
At 54 mm wide (6 × 9 mm pitches), it occupies three standard module positions in a distribution board.
Environmental and durability — 20,000 cycles, tropicalized
Both electrical and mechanical durability are rated at 20,000 cycles. Tropicalization class 2 per IEC 60068-1 means the part is treated against humidity and fungal growth — relevant for installations in coastal or high-humidity environments. IP20 finger-safe terminals are standard for a DIN-rail MCB.