Product Description:

The NFD04.1-440-050 is a passive mains filter produced by Bosch Rexroth Indramat for the NFD Mains Filters series. Installed between the plant’s three-phase supply and the drive controller cabinet, the unit suppresses conducted radio-frequency noise and discharges stored energy after power-down. By limiting electromagnetic interference, it helps protect servo drives and communication hardware from unwanted line disturbances that can interrupt stable operation. It is sized for medium-power converters and mounts close to the mains contactor inside enclosed control panels.

The filter’s stored charge decays to a safe level within 10 s, reducing the delay after shutdown. Attenuation is supported by a high common-mode capacitance of 800 nF, which provides a low-impedance path for high-frequency disturbances to ground. Compliance with industrial supply networks is indicated by its interference rating of Class A, meaning the component is intended for use in industrial environments. Operation on balanced power rails is ensured by its three-phase topology, so all three conductors are filtered symmetrically. For thermal design of the upstream contactor and protective devices, the filter carries a continuous line current of 50 A without derating.

Internal copper windings and core laminations dissipate only 15 W under rated load, allowing enclosure temperatures to remain within drive panel limits when natural convection is available. The filter is matched to converters that run on a nominal line voltage of 3×440 VAC, and it can also be connected to supplies up to 3×460 VAC. This input range suits common industrial utility systems without requiring a different filter for small line variations. The housing weighs 5.0 kg, which helps simplify mounting on DIN rails or side plates inside the control cabinet.