Thanks for all the inputs....... I'll forward them to WG11 members prior to the May meeting.
Best Regards, Mike Hopkins ----- Original Message ----- From: <[email protected]> To: <[email protected]> Cc: <[email protected]> Sent: Thursday, March 28, 2002 2:21 PM Subject: RE: EMC test set-up for device with ethernet connection > Mike, > > A method that surges two units simultaneously (as with coaxial cable) is > good. > > Justification: > > IEEE 802.3 compliance > A link with a 20mH decoupler is atypical and non-compliant with ANSI/IEEE > 802.3 (a.k.a. ISO/IEC 8802-3) Ethernet requirements. Inductance (noted by > Richard Woods) is a problem with 100BaseTX and Gigabit Ethernet. > > Relating test to reality > Although our Ethernet products meet EN61000-4-5 with the 20mH choke, > relating test results to 'lightning strikes in the vicinity' is purely > conjectural. > > Science project vs. immunity test > Non-coax LAN links typically connect two (2) units. Testing the link > eliminates the need to 'invent' new decouplers. Our typical > product-qualification sample is >1; simultaneously surging a second unit is > no problem. > > David Sterner > ADEMCO Group > > -----Original Message----- > From: Michael Hopkins [mailto:[email protected]] > Sent: Thursday, March 28, 2002 12:56 PM > To: [email protected] > Subject: Re: EMC test set-up for device with ethernet connection > > > Each end individually, or the whole link at once?? Each end by itself is > easier (constrained, of course, by the availability of couplers). I'll pass > your comments along to the working group and see if anyone has any ideas. > > Best Regards, > > Mike Hopkins > > > ----- Original Message ----- > From: <[email protected]> > To: <[email protected]> > Sent: Thursday, March 28, 2002 8:10 AM > Subject: RE: EMC test set-up for device with ethernet connection > > > > Mike, > > I would like an 'alternate method' where you can surge the entire link > (i.e. > > both ends). > > > > The EFT test procedure includes a test for a link. Surely it is not > rocket > > science to determine equivalent surge test parameters. > > > > David Sterner > > ADEMCO Group > > Syosset NY > > > > -----Original Message----- > > From: Michael Hopkins [mailto:[email protected]] > > Sent: Wednesday, March 27, 2002 8:47 PM > > To: John Woodgate; [email protected] > > Subject: Re: EMC test set-up for device with ethernet connection > > > > > > > > As convenor of SC77B WG11 which is responsible for the revision of this > > document AND as a manufacturer of simulators and coupler/decouplers, we > > (both the WG members and my company) have investigated a number of ways of > > dealing with coupling to high speed data and telecom lines. > > > > The problem is threefold: > > 1. You need enough back impedance in the line to support the voltage surge > > to be delivered to the load. > > 2. The back filtering must be adaquate to prevent any significant surge > > energy from being delivered back to the auxillary equipment (the source of > > the data). > > 3. The loading on the line from coupling (capacitance) and the impedance > of > > the line from filtering, must be low enough that the data is not reduced > to > > the point where it is unusable. > > > > To date, no one has offered a design that will work for data rates of more > > than about 100kHz. We and other manufacturers have such designs and they > are > > available commercially. > > > > The current recommendation for high speed I/O and data lines is to take a > > leaf from FCC, CCITT (now ITU), and Bellcore standards which test as > > follows: > > > > With the data/telecom line connected, determine that the port is > working > > properly > > Remove the data/telecom line, surge the input. > > Replace the data/telecom line and determine that the port is still > > functional. > > > > If anyone out there has a better recommendation, please let me have it > ASAP. > > Our next meeting is in Berlin in May and we must have a CD of the next > > revision as a result of that meeting. We'll consider any design that is > > submitted. > > > > Best Regards, > > > > Michael Hopkins > > Convenor IEC SC77B WG11 > > [email protected] > > > > > > ----- Original Message ----- > > From: "John Woodgate" <[email protected]> > > To: <[email protected]> > > Sent: Wednesday, March 27, 2002 2:58 PM > > Subject: Re: EMC test set-up for device with ethernet connection > > > > > > > > > > I read in !emc-pstc that [email protected] wrote (in <846BF526A205F8 > > > 4BA2B6045BBF7E9A6A01F13FB2@flbocexu05>) about 'EMC test set-up for > > > device with ethernet connection', on Wed, 27 Mar 2002: > > > >We have recommended to the manufacturer of the surge generator > > > >that the IEC/CENELEC techincal committee include this test method in a > > > >revision of the standard. > > > > > > You should make the same proposal to IEC SC77B through your national > > > committee of the IEC. The equipment manufacturer may be reluctant to > > > support a proposal that requires modification to his product. > > > -- > > > Regards, John Woodgate, OOO - Own Opinions Only. > > http://www.jmwa.demon.co.uk > > > Interested in professional sound reinforcement and distribution? Then go > > to > > > http://www.isce.org.uk > > > PLEASE do NOT copy news posts to me by E-MAIL! > > > > > > ------------------------------------------- > > > 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] > > > > > > All emc-pstc postings are archived and searchable on the web at: > > > http://ieeepstc.mindcruiser.com/ > > > Click on "browse" and then "emc-pstc mailing list" > > > > > > > > > ------------------------------------------- > > 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] > > > > All emc-pstc postings are archived and searchable on the web at: > > http://ieeepstc.mindcruiser.com/ > > Click on "browse" and then "emc-pstc mailing list" > > > ------------------------------------------- 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] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
