The TeSys LX4FK165 is a DC-operated contactor coil from the TeSys FK range, designed as a service part for TeSys FK contactors. It is a replacement coil, not a standalone contactor — it mounts onto the FK contactor frame to provide the magnetic flux that pulls in the main contacts. The coil is rated for 165 V DC control voltage, with a DC low-consumption design. It draws an inrush current through a 23.5 Ohm winding at 68 °F (20 °C), then drops to a holding current through the 5618 Ohm winding at the same temperature — this two-stage resistance is typical of DC economizer coils that reduce power dissipation once the contactor is sealed. Operating time is 45 to 60 ms for opening and 50 to 60 ms for closing, which is within the normal range for a contactor of this frame size. The coil has no built-in suppressor module, so an external flyback diode or RC snubber must be added across the coil terminals if the control circuit requires it — without suppression, the inductive kick from coil de-energization can damage solid-state outputs or cause EMI issues in the panel.
The control voltage limits are: dropout at 0.2 to 0.35 Uc (33 to 58 V DC) at 131 °F (55 °C), and operational range of 0.85 to 1.1 Uc (140 to 182 V DC) at the same temperature. This means the coil will hold in down to about 140 V DC, but will drop out below roughly 58 V DC — useful to know if your DC bus has significant ripple or brownout conditions. Ambient temperature range for operation is 23 to 131 °F (-5 to 55 °C). This is standard for indoor panel use; if the coil is in a non-climate-controlled enclosure near a furnace or in a desert environment, the upper limit may be a constraint.