The Schneider Electric C25N42D160 is a ComPacT NSX moulded-case circuit breaker from the NSX250N frame, rated 160 A at 40 °C with a MicroLogic 2.2 electronic trip unit. It's a 4-pole (4P) unit built for distribution duty per EN/IEC 60947-2, with a breaking capacity code of N — 50 kA Icu at 415 V AC. That 50 kA at 415 V is the number that governs most panelboard and switchboard applications in common 400 V industrial networks; the 90 kA at 240 V is there for low-voltage utility-side tie points. The MicroLogic 2.2 provides L (long-time overload), So (short-time short-circuit with fixed delay), and I (instantaneous) protection curves — all electronic, so no thermal bimetal drift over the life of the breaker.
This breaker carries a 50 kA Icu at 380/415 V AC and 440 V AC, and 36 kA at 500 V AC. For a 480 V system (common in North American industrial plants), the UL-trace rating is 50 kA Icu. At 600 V AC it drops to 15 kA. The key takeaway: at 415 V you have full 50 kA interrupting capacity, which covers most secondary distribution in European and Asian 400 V networks. At 690 V it's 10 kA — usable but tight for high-fault locations. Category A utilisation means it's not intended for current-limiting duty in series with downstream breakers; selectivity studies should account for that.
Mounts on a backplate (not DIN rail) in either horizontal or vertical orientation, flat on the back. The 35 mm connection pitch matches standard busbar and cable-lug spacing. Front-connectable on both line and load sides — no need to rotate the breaker for rear-access panels.