Single-phase block filter with added ground choke

Schurter's FMAB NEO single-phase filter series is now supplied with enhanced asymmetrical attenuation performance in higher frequencies, accomplished by adding a ground line choke on the earth conductor. The new filter series presents a simple solution to filtering critical earth conductor currents caused by today's power conversion technologies, such as those utilising high-speed switching power supplies, frequency converters, and motor drives.

Due to the inherent electromagnetic interferences being generated in and between different systems, poorly suppressed interferences can impact the operation of the equipment or other nearby devices. To fulfil these EMC challenges, engineers are looking for high-performance filters which will also fit in smaller spaces. As well as the current-compensated choke on the line and neutral conductor, the device provides a second choke on the earth line. The ground line choke is located between the filter input and output. With the two earth connections at the input and output, the earth connection at the main input is insulated from the housing. This provides that possible high-frequency interference currents on the earth conductor cannot bypass the filter through the housing. Applications with critical high-frequency earth line currents incorporate medical and laboratory equipment, audio and video, and industrial automation systems. Medical filters without Y-capacitors significantly benefit from an improved asymmetrical attenuation in the higher frequency range due to the earth conductor choke.

This single-stage filter family is ENEC and cURus-approved. The rated current range is 1-60A at 40C. The temperature range is from -40C to +100C with deratings according to rated current. The rated voltage is 125/250V. Variations include models with PE Choke, Protection Class II, Standard leakage current at 1mA and Medical low leakage M80 or M5. Mounting options offer bolt and nut or quick-connect terminals. Wire leads are also available on request.