[SI-LIST] Re: physics behind EMI powerline filters

  • From: Juergen Hannappel <hannappe@xxxxxxxxxxxxxxxxxx>
  • To: "SI-LIST" <si-list@xxxxxxxxxxxxx>
  • Date: 27 Nov 2001 18:46:38 +0100

"Muriel Bittencourt de Liz" <muriel@xxxxxxxxxxx> writes:


> - What, physically speaking, happens to the EMI energy that leaves the equi=
> pment when I add a filter??? When there is no filter, I understand that the=
>  energy goes to the mains?? Does the filter reflect the EMI energy, keeping=
>  it "arrested" inside the equipment?

This energy is converted into heat, either by the ohmic restistance of
the filter materials as eddy currents run there or by polarizing and
re-polarizing the dielectrics in the capacitors or some other
mechanism. The details vary...

Dr. Juergen Hannappel  Office: W148 Phone: +49 228 73 2447  FAX +49 228 73 7869
mailto:hannappel@xxxxxxxxxxxxxxxxxx        Physikalisches Institut der Uni Bonn
http://lisa2.physik.uni-bonn.de/~hannappe   Nussallee 12, D-53115 Bonn, Germany
CERN: Phone: +412276 76461 Fax: 77930 Bat. 892-R-A13 F-01631 CERN CEDEX, France
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