The Schneider Electric C104TM100D is a thermal-magnetic trip unit for the ComPacT NSX100...250 DC series, rated 100 A at 40 °C and 750 V DC across 4 poles (4D protected). It's built for DC distribution networks — think battery banks, DC bus systems, or solar combiner boxes — and carries the EN/IEC 60947-2 standard for low-voltage switchgear. The TM-D trip unit gives you fixed long-time and instantaneous protection (LI), so the overload curve and short-circuit pickup are set at the factory; you adjust only the long-time pickup from 0.7 to 1 x In.
The 750 V DC rating means this trip unit handles the full voltage of a typical 600 VDC bus plus headroom — common in traction, UPS, and industrial DC drives. The 4D protected poles mean all four poles switch and protect the DC circuit, which matters for ungrounded or bipolar DC systems where you need full isolation.