SCHURTER is expanding the successful FMAB NEO single-phase filter family with new variants. The filter is now available with an additional ground line choke to suppress high-frequency interference on the earth conductor. The new filter series is available in standard and medical versions for a rated current range of 1 A to 20 A with plug-in connections.

Standard filters only filter the pole and neutral conductors, the earth conductor stays untouched. This can be a problem with the occurrence of high-frequency earth conductor currents, because in this case, even the best filter can’t do any improvements. The new filter versions with integrated earth conductor chokes offer a simple solution.

Ground choke
New variants of the FMAB NEO single-phase filters are equipped with an earth conductor to choke. In addition to the current-compensated choke on the pole and neutral conductor, the mains filters have a second choke on the earth conductor. The earth conductor choke is located between the filter input and output. The filters, therefore, have two earth connections at the input and output, whereby the earth connection at the mains input is insulated from the housing. This ensures that possible high-frequency interference currents on the earth conductor cannot bypass the filter via the housing. Especially medical filters (without Y-capacitors) benefit from an improved asymmetrical attenuation in the higher frequency range due to the earth conductor choke.

Applications
Filters with earth line chokes are used in most applications with critical high-frequency earth line currents. High-frequency earth conductor currents are generated by any type of fast energy conversions such as switching power supplies, frequency converters or motor drives. Earth loops can occur in devices that are connected to other devices with shielded cables. The high-frequency interference current occurring on this earth loop is effectively attenuated with a ground choke. Typical applications are medical and laboratory equipment, audio and video as well as industrial systems.

Approvals
The single-stage FMAB NEO filter family has a particularly compact design combined with high performance. It is suitable for applications in the temperature range from -40 °C to +100 °C and has ENEC and cURus approvals.

• Filter with ground choke
• Excellent symmetrical attenuation
• Fully closed steel housing
• Optional wire leads