The LX4D6TD is a replacement coil for the TeSys D contactor range, rated for 305 V DC control voltage. It is a DC standard coil type, meaning it is designed for continuous DC control circuits without an integrated rectifier — the coil itself is wound for DC, not an AC coil with a bridge rectifier added externally.
This part is obsolete per the manufacturer. If you are designing a new panel, the current TeSys D coil range should be reviewed for a 305 V DC equivalent; the control circuit voltage limits are 0.85...1.1 Uc at up to 55 °C, so any replacement must hold in at 259 V DC and not exceed 335 V DC.