Let's assume for a moment that the answer is, "yes", that programmable driver IC chips can be considered "regulating networks". Since these parts are not certified how can you be sure that they are appropriate to use in your application? The answer to that is "test".
We use such programmable parts in some of our designs known as a "High-Side Driver" IC. They come out of the automotive product line and are fantastic parts. They use them in cars to turn on and off lights and accessories. You can overload them, short them out, subject them to rf, surges, ESD, etc. and they just keep working. When we "test to failure" they always fail with no output (safely). We have never been able to get them to fail in an unsafe way (excessive current). For us to qualify them we test them according to the standard; we overload them until they shut down, then reduce the load slightly and run them for up to 4 hours. We insure that all traces, cable, wires, connectors, etc. can handle the max overload current without overheating. We short the output as well but these ICs shut down and go into a pulse mode where every few seconds they test to see if the short has been removed. Once the short is removed the output voltage is restored. Even though we have a high confidence level in these parts they still are not certified as an overcurrent protection device. So, whenever we use them to drive an I/O cable, we always include a certified overcurrent protection device (OCPD). I take heat for this all the time because to be competitive these days you have to watch every penny and our design teams argue that the certified OCPD is not required, and our testing supports their position. They argue that regulating network that pass the overload and short test should be adequate for safety. I'm not sure how an NRTL or NB would view these parts. I imagine some labs would have issues, and others would test and let it go. I imagine it will remain a gray area with us for some time. I wish we could come up with a definite answer for these parts. The Other Brian From: Crane, Lauren [mailto:lauren.cr...@kla-tencor.com] Sent: Friday, January 31, 2014 1:54 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Meaning of "regulating network" in 61010-1 Does anyone have a clear idea as to what "regulating network" means in 61010-1:2010 section 9.4? The "Other Brian" asked a similar question in 2009, but did not get an answer (ref https://www.mail-archive.com/emc-pstc@listserv.ieee.org/msg60829.html ) Borrowing from his message (and updating to the new revision of the standard) The 61010-1 standard in section 9.4 calls out three methods that can provide a "Limited-Energy" Circuit; 1) inherently limited circuit; 2) over current protection device, and 3) a Regulating Network. e.g. would a programmable driver chip qualify as a "regulating network"? Regards, Lauren Crane KLA-Tencor - ---------------------------------------------------------------- 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 <emc-p...@ieee.org<mailto:emc-p...@ieee.org>> 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://www.ieee-pses.org/list.html (including how to unsubscribe)<http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net<mailto:emcp...@radiusnorth.net>> Mike Cantwell <mcantw...@ieee.org<mailto:mcantw...@ieee.org>> For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org<mailto:j.bac...@ieee.org>> David Heald <dhe...@gmail.com<mailto:dhe...@gmail.com>> ________________________________ LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - ---------------------------------------------------------------- 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 <emc-p...@ieee.org> 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://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
