This is the core overcurrent protection device for a distribution panel or motor branch circuit — it handles the load current continuously and clears faults up to its interrupting rating. The TMF trip provides a fixed thermal curve for overloads and a fixed magnetic pickup for short-circuits, so coordination studies should confirm the trip settings match the downstream load profile before panel assembly.
Integration Notes
The TMF trip unit is non-interchangeable in the field — the 125 A rating is fixed at the factory. When wiring, the line and load terminals accept copper or aluminum conductors sized per the terminal marking; torque values for the lug screws are specified on the breaker label. For selective coordination, verify that the magnetic pickup threshold does not overlap with the inrush of downstream motor starters or soft starters.