From: "Tarver, Peter" <[email protected]> Sent: Friday, April 27, 2007 4:25 PM > > Your approach is a good one. The problem is with the standard. Even > before IEC60950-1:2005 was published, there were proposed corrections to > the Creepage Distance tables we discussed a few months ago. I suspect it > was intended that ยง1.5.9.2 was to apply only to those circuits where > transients are known safety concerns: ac mains and exposed tnv. I have no > hard evidence for this assertion, but it's what makes the most sense to > me.
Hi Peter, Thanks for your answers. May be based on 1.3.1 - "The requirements detailed in this standard shall be applied only if safety is involved." I should decide that in described by me situation safety is not involved ? Really I have about 25 low voltage, low current inputs and outputs in my device, but because of EN 50130-4 I need surge protect all of them. Then how to be sure for each of them that safety is no a concern here. My device is powered from AC 230V by external DC 12V power supply, and in most cases devices connected to my inputs are powered from the same 12V source, so really no possibility to overvoltage the 33V TVS, but I can't exclude connecting some other devices powered from other sources to my inputs. I suppose to use TRANSILs and no VDR to avoid my own question ;-) Best Regards Piotr Galka - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
