The LX9FJ937 is a specific contactor coil from the TeSys F range, designed to operate a TeSys F contactor at 440 V AC (40–400 Hz) or 440 V DC with low consumption. It pulls in at 500 VA inrush and holds at 23 VA, with a closed-circuit inductance of 19 H. Opening time is 60 ms, closing 50 ms — figures that matter when coordinating contactor timing in a motor starter or transfer scheme.
The control circuit accepts 440 V AC across 40–400 Hz or 440 V DC, with operational limits of 0.85–1.1 Uc at 55 °C and drop-out between 0.3–0.5 Uc. That drop-out range is wide enough to ensure the contactor releases cleanly on a sagging control supply — important for undervoltage protection schemes. The coil draws 386 Ω inrush and 3690 Ω holding at 20 °C, so verify your control transformer sizing: the inrush VA (500 VA) is the peak load, not the steady-state draw. Heat dissipation runs 11.4–13.9 W depending on control voltage and duty. In a densely packed panel, that heat adds up — allow ventilation or spacing around the contactor if multiple coils are energized continuously. The coil comes without a built-in suppressor module. If your control circuit uses solid-state outputs or a PLC driving the contactor, add an external RC snubber or varistor across the coil to suppress the inductive kick on de-energization.
Where it belongs in the panel
This coil mounts onto a TeSys F contactor frame — it is the interchangeable coil that lets you field-change the control voltage without replacing the whole contactor. No wiring changes at the power terminals, just the control leads to the coil.