Are you both using the same ESD simulator? There's a huge difference between different brands, with some producing large radiated E-fields.
Kenneth Wyatt Wyatt Technical Services LLC Woodland Park, CO [email protected] www.emc-seminars.com (Sent from my iPad) On Mar 6, 2013, at 5:48 PM, "McInturff, Gary" <[email protected]> wrote: > The problem is I don’t know if it makes a difference Dan. We certainly were > getting different results from a lab – and I trust the lab itself. But it > didn’t match what I had here nor the results from my normal certification > lab. We tested two units and got the same results, and now the customer uses > yet another lab with different results. Even given the vagrancies of ESD > testing I can’t put my finger on the problem. That’s what got me to verifying > the setup. Incidentally during the original successful tests I actually tried > it both ways, with the bleed cables in parallel, and with the HCP cable > removed – as I suspect should be the case (maybe) and that didn’t make a > difference at that time. > But as I said I’m trying to eliminate the easy stuff first – test setup, both > mine and the lab that is failing the equipment. > > Thanks > > Gary > > > Gary > > From: Dan Roman [mailto:[email protected]] > Sent: Wednesday, March 06, 2013 4:44 PM > To: McInturff, Gary; [email protected] > Subject: RE: [PSES] test setup for table top ungrounded equipment 61000-4-2 > IEC:2008 figure 6 page 20 > > Interesting. I have done the testing with the bleeder cable as described > connected in parallel, not in series with the HCP bleeder. Maybe I was doing > it wrong though? But as you said, it does not make sense—but does it make a > difference? Is it shown as set up that way merely as a closer more > convenient connection to the EUT? Reading the text and ignoring figure 6 > would lead me to believe it was in parallel. > > ______________________________________________________ > Dan Roman, N.C.E. > VP of Communications Services > IEEE Product Safety Engineering Society > mailto:[email protected] > > > > > From: McInturff, Gary [mailto:[email protected]] > Sent: Wednesday, March 06, 2013 6:20 PM > To: [email protected] > Subject: [PSES] test setup for table top ungrounded equipment 61000-4-2 > IEC:2008 figure 6 page 20 > > Ladies and germs > I was confirming this set-up and found something confusing. > The picture shows the cable which is used to remove charge from the EUT > between successive ESD discharges and having 2 470k Ohm resistors, the same > basic setup as between HCP and ground plane or VCP and ground plane. Not > surprising, but in looking at the picture it implies that this cable ends up > being in series with the HCP/GP bleeder cable. That would make the series > resistance during discharge to be rough 2 Mohm rather than 1 Mohm. That > doesn’t seem right to me. The reference text doesn’t really what happens to > the hcp discharge cable either. In fact the cable for the VCP would seem to > be placed in parallel with the HCP bleeder cables during indirect contact > discharges to the VCP. I don’t believe that is true either. > I believe for the VCP setup the HCP cable is disconnected from the HCP and > then hooked up to the VCP. I kind of expected the bleeder cable for the > ungrounded equipment bleeder cable would do the same thing. The HCP cable > removed and it could be used as the EUT bleeder resistor wire as well. > > In the first case the bleeder and the HCP bleeder cable appear to be in > series, and in the second the bleeder and the HCP would be in parallel if it > wasn’t disconnected from the HCP. > > I do have a pdf of the figure but not allowed to attach to this email. > > Thoughts. > > Gary McInturff > Reliability/Compliance Engineer > > > > > Esterline Interface Technologies > Featuring > ADVANCED INPUT, GAMESMAN, LRE MEDICAL, and MEMTRON products > 600 W. Wilbur Avenue > Coeur d’Alene, ID 83815-9496 > Toll Free: 800-444-5923 X1XXX > Tel: (208) 635-8 > Fax: (208) 635-8 > > www.esterline.com/interfacetechnologies > > Technology, Innovation, Performance… > > Click here to read disclaimer > > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <[email protected]> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used > formats), large files, etc. > > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <[email protected]> > Mike Cantwell <[email protected]> > > For policy questions, send mail to: > Jim Bacher <[email protected]> > David Heald <[email protected]> > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <[email protected]> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used > formats), large files, etc. > > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <[email protected]> > Mike Cantwell <[email protected]> > > For policy questions, send mail to: > Jim Bacher <[email protected]> > David Heald <[email protected]> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
