Schneider Electric M9F23110 Supplementary Protector

This UL 1077 supplementary protector provides overcurrent protection within equipment. Select it for supplementary protection, with branch-circuit protection handled separately.

The fixed 10A rating is the basis for current selection, and the thermal trip is calibrated at 25°C. Account for load current and ambient temperature because temperature affects thermal trip response.

The thermal element responds to sustained overloads, while the magnetic element responds to high fault currents. A D curve tolerates higher brief inrush before instantaneous tripping. Check startup demand and fault-clearing requirements during selection because the trip is fixed.

The rated voltages are 240VAC, 415VAC and 60VDC, with a 50/60Hz frequency rating for AC use. Select by both circuit voltage and AC or DC operation, then check the interrupting rating applicable to that circuit.

At 240VAC, the interrupting rating is 14kA and Icu is 10kA; at 415VAC, Icu is 3kA. At 60VDC, Icu is 20kA. Compare available fault current at the installation point with the applicable voltage-specific rating under the governing standard.

The screw-clamp terminals accept 18-8 AWG wire. Select a conductor within that range and tighten the terminals to 22.1 lb-in (2.5 N·m) for the required termination torque.

It mounts on DIN rail and measures 3.2 in high, 0.7 in wide and 2.8 in deep. Use these dimensions when laying out the installation and arranging access to the toggle and terminals.

The operating temperature range is -30 to 70 °C. Keep the local ambient temperature at the protector within that range, including heat generated by nearby equipment.

A toggle provides manual operation, and a trip indicator helps distinguish a protective trip from an intentional opening. Use the indication during troubleshooting and investigate the overcurrent cause before restoring operation.