The Schneider Electric TeSys LX4FG055 is a replacement contactor coil designed for the FG series of contactors. It operates on a 55 V DC control circuit, drawing an inrush current through a 3.87 Ohm coil resistance at 68 °F (20 °C) before settling to a holding current through the 904.1 Ohm holding resistance at the same temperature. The coil lacks a built-in suppressor module, so external flyback diode or RC snubber protection is required on the control circuit to prevent voltage spikes during de-energization.
Electrical characteristics and operating envelope
The coil's operating time is specified at 30...40 ms for closing and 30...50 ms for opening. The control circuit is classified as DC wide range, with operational voltage limits of 0.85...1.1 Uc (46.75...60.5 V DC) at 131 °F (55 °C) and a drop-out threshold of 0.15...0.2 Uc (8.25...11 V DC) at the same temperature. Ambient air temperature for operation is rated from 23...131 °F (-5...55 °C). These limits define the reliable pick-up and drop-out envelope; operation outside these ranges risks partial stroke or failure to hold.
This coil mounts directly onto the FG series contactor armature. The DC wide-range control circuit requires clean DC supply; verify the power supply can deliver the inrush current without voltage sag below the 0.85 Uc pick-up threshold. Because the coil has no built-in suppressor, the panel builder must install a freewheeling diode across the coil terminals, polarity-observed, to protect the control circuit PLC output or relay contact from inductive kickback.