EMC Line Filters and EMC Filter Design Kit

April 27, 2020 by Paul Shepard

Würth Elektronik is available to help prevent EMI problems with non-compliant equipment with a choice of ready-to-use EMC line filters and a "Design Your Own EMC Filter" kit. Würth offers complete WE-CLFS EMC Line Filters. These have most components one needs for an EMC filter inside of a welded enclosure for perfect shielding.

All WE-CLFS filters have at least 65dB of peak attenuation, and come with UL and VDE certifications, which ensures safety requirements are already factored into the design. With 3 different types available: single stage, single-stage advanced, and two-stage, with options of with a rated current up to 20A.

WE-CLFS EMC Line Filters.

Another solution Würth Elektronik offers is the "Design Your Own EMC Filter" kit, which includes different common mode chokes (CMCs), X capacitors, Y capacitors, and connectors, as well as a booklet including pre-determined filters which eliminate calculations and component selection. This kit will enable the user to assemble a working EMC filter during design.

Design Kit Features

  • Test-PCBs offer an easy way to build up a line filter
  • Common mode chokes suppress common mode noise
  • X-Capacitors short differential mode noise to neutral
  • Y-Capacitors short common mode noise to ground
  • Resistor discharges X-Capacitors

For the off-the-shelf power supply's radiated emissions, a cable ferrite is the easiest solution. Würth Elektronik's free component selection tool, REDEXPERT, allows users to sort through all cable ferrites, including parts to fit specific cables, to find the best solution in just a few seconds.