The Schneider Electric C104MG040 is a TM40G thermal-magnetic trip unit from the ComPacT NSX100…250 range, rated 40 A at 40 °C with 4 poles (neutral fully protected, 4D). It carries EN/IEC 60947-2 certification for use in DC and AC networks up to 690 V AC 50/60 Hz or 750 V DC — the voltage rating covers both common industrial line voltages and DC bus applications. The LI protection profile (thermal overload + magnetic short-circuit) is fixed for instantaneous pickup at 80 A, with long-time pickup adjustable from 0.7 to 1 x In.
The trip unit mounts into a ComPacT NSX100…250 fixed-mount breaker frame. Neutral is on the left; the 4D configuration means the neutral pole is fully protected with the same thermal-magnetic elements as the phase poles. IP40 front-face protection is standard — the breaker enclosure itself handles the rest.
The long-time delay is fixed at 120…400 s at 1.5 x In, so coordination studies should account for that non-adjustable band. No earth-leakage protection is integrated — if ground-fault detection is needed, it must come from an external module or a different trip unit variant.