The TM-D gives you fixed thermal overload (L) and fixed magnetic short-circuit (I) protection — no interchangeable rating plugs, no electronic adjustments. What you set at the factory is what you get in the field, which simplifies spares stocking but means the trip curve is locked to the 250 A frame. At 415 V AC, the C25F3TM250C delivers 36 kA Icu per IEC 60947-2. At 220/240 V it jumps to 85 kA Icu. The 3-pole (3P) version protects three phases; the TM-D trip unit covers all three poles (3D protected poles). No earth-leakage module is integrated — if you need ground-fault protection, you add a separate Vigi module or an external relay.
Mounts to a backplate — no DIN rail, no snap-on. The 105 mm width, 161 mm height, and 86 mm depth fit the standard ComPacT NSX cutout. Rated IP40 from the front, IK07 impact resistance. Power dissipation is 18.75 W per pole, so at full 250 A load the breaker dumps about 56 W into the enclosure.