The LX4FF350 is a replacement contactor coil from the Schneider Electric TeSys range, designed for DC control circuits at 350 V DC. It's a DC low-consumption coil with no built-in suppressor module, so you'll need to add external flyback suppression if the circuit demands it. Closing time runs 30 to 40 ms; opening takes 30 to 50 ms. The coil holds at 350 V DC nominal, with an operational range of 0.85 to 1.1 Uc (298 to 385 V DC) at 55 °C, and drops out between 0.15 and 0.2 Uc (52.5 to 70 V DC). Ambient operating temperature is -5 to 55 °C.
No official successor order code appears in the lifecycle record. If you're filling a service spare or a line-down replacement, the safest route is to source a sealed surplus unit against an RFQ. Condition is everything here — verify the coil hasn't been sitting in a damp warehouse for a decade.
The 350 V DC control voltage is specific — this isn't a 24 V or 110 V coil. If your panel runs a 350 V DC control bus, this coil drops right in. If not, you'll need a different coil from the TeSys FF family or an external DC-DC converter. The 30-40 ms closing time is typical for a contactor of this size; it's not a fast-switching application like a DC drive precharge. The coil's average holding resistance is 34,910 ohms at 20 °C, with an inrush resistance of 199.7 ohms. That inrush-to-hold ratio is normal for a DC coil — the initial current spike is about 175 times the holding current, so make sure your control transformer or DC supply can handle the surge without dropping out.