Hi Doug:
That's an unusual set of requirements. Is this a conventional Ethernet transceiver application for twisted-pair, or something different? Any Ethernet transformer that complies with the IEEE 802.3 standard will be rated for 1500 VRMS isolation and should easily meet your 1200 VDC requirement for primary-to-secondary isolation. However, this is just a voltage test and there are no corresponding guarantees for internal creepage, clearance, or distance through solid insulation. So, specifying only the external creepage distance may not be adequate, depending on what particular requirements you are trying to meet. That being said, if your 5.1 mm creepage distance requirement applies primary-to-secondary, most Ethernet transformers put all the primary pins on one side of the package, and all the secondary pins on the other side of the package. For primary-to-secondary creepage distance, there is no need to be concerned with the separation of adjacent pins on the same side of the package. You should be able to achieve your 5.1 mm goal with the side-to-side separation of most Ethernet transformers. One particular Ethernet transformer that was explicitly designed for high primary-to-secondary isolation (5000 VRMS) is the Bourns SM51589PEL. The external primary-to-secondary creepage distance of the package is approximately 10 mm. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 (USA) <mailto:[email protected]> [email protected] <http://www.randolph-telecom.com> http://www.randolph-telecom.com From: Doug Powell [mailto:[email protected]] Sent: Monday, November 03, 2014 12:22 PM To: [email protected] Subject: [PSES] Network Isolation Transformer All, I am searching for an ethernet isolation transformer that has a PRI to SEC safety isolation rating of at least 1,200 VDC. On top of that a surface mount version is preferred but not essential. I am able to identify several with a manufacture rating high enough but pad-to-pad creepage distance is only about 1.5 mm on the surface of a PCB and I need at least 5.1 mm. I appreciate hearing about any sources you might be able to identify for me. Doug -- Douglas E Powell [email protected] <mailto:[email protected]> Skype: doug.powell52 http://www.linkedin.com/in/dougp01 - ---------------------------------------------------------------- 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] <mailto:[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://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 <[email protected] <mailto:[email protected]> > Mike Cantwell <[email protected] <mailto:[email protected]> > For policy questions, send mail to: Jim Bacher <[email protected] <mailto:[email protected]> > David Heald <[email protected] <mailto:[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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
