Dear group, The use of ground choke in conducted measurements was specified in "Verfügerung 1046/1982" when testing to comply with VDE 0871 if the measured noise was closer to the limit than 5 dB. This second measurement must then also comply with the limit. The value of this ground conductor choke was specified to 1.6 mH.
I believe the reason for this sophisticated measurement were required because the inductance in ground lead in really live may increase the noise level with several dB's. I hope this clarified the matter. Best regards Helge Knudsen Jyske EMC Denmark [email protected] -----Original Message----- From: Cortland Richmond [SMTP:[email protected]] Sent: lørdag, december 05, 1998 05:43 To: Gary McInturff; ieee pstc list Subject: RE: Doubt on LISN utilization As I recall, when testing conducted emissions to VDE 0871, it was required to observe noise in the two powered lines with the switch both open and closed, and use the higher result. Some power supplies would in fact give different results if the ground was opened. An aside: I used to work at Tandy Computer's R&D. When Tandy quit making computers (and I was laid off), I was able to buy a Rhode and Schwarz LISN they scrapped -- for $25. It has the ground switch Muriel describes. When I bought it for Tandy, it cost much, much more! Cortland --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
