40 A MCCB for distribution panels
The TM-D trip unit combines a thermal bimetal for overload protection and a magnetic coil for short-circuit protection; it is a fixed-trip design with no interchangeable rating plugs, so the 40 A is the only trip setting. For a 415 V three-phase supply with a typical transformer impedance, that covers most commercial and light-industrial installations up to a 2000 kVA transformer.
The C11N3TM040B mounts on a backplate — not a DIN rail — via four M6 screws on a 9-module pitch (81 mm wide, 137 mm high, 80 mm deep). The front-facing terminals accept compression lugs or busbars for both line and load connections. The grey (RAL 7016) housing is standard for Schneider's ComPacT NSXm range and matches other panel components in the same finish. Operating altitude is 2000 m without derating, 5000 m with derating — relevant for high-altitude sites where air density affects arc extinction.