TeSys F Contactor — 275 A, 90 kW at 400 V
The Schneider Electric LC1F1857Q7 is a 3-pole TeSys F contactor rated for 275 A operational current (AC-3 at ≤440 V) and switches motor loads up to 90 kW at 380–400 V AC-3, or 100 kW at 415 V and 440 V. The 380 V AC coil draws 1070 VA inrush and holds at 9.9 VA. This is a heavy-duty frame sized for induction furnace duty (AC-1, AC-3, AC-4 utilisation categories) and mounts to a plate, not a DIN rail.
The 275 A AC-3 rating at ≤440 V is the load-bearing figure for motor switching — that is the current the contactor handles during starting and running of a squirrel-cage motor. For resistive loads (AC-1), the thermal current Ith is 275 A at 50 Hz, with 0.33 mOhm average impedance and 25 W dissipation per pole. The rated breaking capacity is 1480 A per IEC 60947-4-1, which governs fault interruption. Insulation voltage is rated 1000 V per IEC 60947-4-1 and 1500 V per VDE 0110 Group C, giving headroom for 690 V systems.
Designed and tested to IEC 60947-4-1, IEC 60947-1, EN 60947-1, EN 60947-4-1, and JIS C8201-4-1. Overvoltage category III. IP2X on the front face with shrouds per IEC 60529 and VDE 0106. Protective treatment TH for tropical environments.
Plate-mounted — no DIN-rail clip. Power circuit uses bolted bar connections (2 x 25 x 3 mm) or ring terminals up to 150 mm². Control circuit uses screw clamp terminals accepting 1–4 mm² flexible or solid. Tightening torque: 18 N·m on the power circuit, 1.2 N·m on the control circuit. Mechanical durability is 10 million cycles; maximum operating rate is 2400 cycles per hour at 55 °C.