The Schneider Electric C10N3TM040C is a ComPacT NSX100N circuit breaker with a 40 A thermal-magnetic TM-D trip unit, three protected poles, and an N-frame breaking capacity of 50 kA Icu at 415 V AC. It sits in the distribution-grade ComPacT family, designed for panelboard and switchboard mounting on a backplate with front-front connections — both line and load terminate on the front face, which simplifies busbar layout and cover cutouts in a standard enclosure.
The 50 kA Icu at 380/415 V AC is the headline number that governs fault-current withstand in a 400 V distribution board — it means this breaker can safely interrupt a short-circuit fault up to 50 kA without welding contacts or rupturing the arc chamber, per IEC 60947-2. At 220/240 V the same frame handles 90 kA Icu, and at 690 V it drops to 10 kA Icu; the N-frame rating (50 kA at 415 V) is the most common selection for 400 V commercial and industrial main or feeder duty. The thermal-magnetic TM-D trip provides L (overload, thermal) and I (short-circuit, magnetic) protection in one unit, with the magnetic pickup fixed at a multiple of In — no electronic adjustment, which means simpler commissioning and fewer nuisance-trip variables on motor-starting or transformer-inrush profiles.
Integration and physical fit
Mounts on a backplate in any orientation — horizontal, vertical, or flat — with front-front wiring that keeps the enclosure depth to 86 mm. The 105 mm width and 161 mm height fit standard 3-pole MCCB cutouts in distribution panels. IP40 front-face protection and IK07 impact resistance handle routine panel access and tool drops during maintenance. The 5.47 W power dissipation per pole (16.4 W total at rated load) should be factored into enclosure thermal calculations, especially in a multi-breaker lineup.
Rated for 50,000 mechanical cycles and 50,000 electrical cycles at 440 V at rated current — that is a solid 20+ year service life in a typical distribution board cycled a few times per week.