The Schneider Electric C40N3TM400 is a 3-pole ComPacT NSX400N moulded-case circuit breaker with a TM-D thermal-magnetic trip unit rated 400 A at 40 °C. The N breaking capacity code means it delivers 50 kA Icu at 380/415 V AC 50/60 Hz per EN/IEC 60947-2 — that is the fault current it can safely interrupt without damage, so it fits distribution panels where the prospective short-circuit current at the bus is up to 50 kA at 415 V. The thermal-magnetic trip provides L (overload, thermal) and I (short-circuit, magnetic) protection in one unit, with no earth-leakage module built in. The 140 mm width and 255 mm height fit standard NSX400N cutouts; the 110 mm depth leaves clearance for front-connect cables.
Integration notes for panel builders
The toggle handle provides a clear contact-position indicator — useful for lockout/tagout verification. Electrical durability is 12,000 cycles at 440 V at half rated current, 6,000 cycles at full rated current; mechanical durability is 15,000 cycles. The IP40 front face and IK07 impact resistance suit enclosed distribution boards where the breaker is not directly exposed to washdown.