My opinion. The frequencies radiated by the output leads of an SMPS are such that the wires are the only significant radiator, not the loads. So it would not matter if the loads were within the cell, or without. But it is easier to put them within the cell and not worry about filtering the leads, unless heat build-up is an issue. If this is an SMPS for a PC or a similar application with very short output leads then I see no problems, but if it were a stand-alone power supply that drives long leads, then the radiation efficiency of wires within a typical TEM cell will not represent the real world and it would be better to monitor current on the wires and predict the radiated fields from real world-length wires with the measured current. Ditto for the input power leads, except here it is a given the leads are long.
Ken Javor on 2/20/03 1:51 PM, Muriel Bittencourt de Liz at [email protected] wrote: > > Group, > > I have a doubt concerning radiated emissions measurement: > > - For radiated emissions measurement of switched mode power supplies using a > TEM cell, should I leave the loads of the supply inside or outside the > cell?? My TEM cell have filtered connections for DC loads. > > Thanks in advance for your help. > > Best Regards, > > Muriel > > > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: [email protected] > Dave Heald: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > Archive is being moved, we will announce when it is back on-line. > All emc-pstc postings are archived and searchable on the web at: > http://www.ieeecommunities.org/emc-pstc > This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
