What about floating the DC supply with suitably rated isolation transformer and reversing relay, and building a cage around all three components?
The EUT chassis can then remain grounded. Best Regards, Mike From: Douglas Powell [mailto:[email protected]] Sent: Tuesday, August 04, 2015 7:33 AM To: [email protected] Subject: Re: [PSES] Dual polarity DC electric strength test It would seem that you need a piece of test gear with a floating output that can have either end referenced. Not sure I have seen anything like this. Best, Doug. From: Greg McClure Sent: Tuesday, August 4, 2015 8:30 AM To: [email protected]<mailto:[email protected]> Reply To: Greg McClure Subject: Re: [PSES] Dual polarity DC electric strength test Doug, John, We have discussed these options with our test equipment group and could build the test fixtures as suggested. However, we hesitate to use a reversing scheme with a switch or high voltage relay in manufacturing because it would require making the chassis of the product hot for one polarity and our practice has always been to keep the chassis/frame at ground potential to make it safer for the operator. We could build a cage that prevents access to any part of the EUT but that would require a major change to the design of the hi-pot station. Gregory H. McClure Lexmark Product Safety 859 232 3240 office 859 232 6882 fax On Tue, Aug 4, 2015 at 9:43 AM, Greg McClure <[email protected]<mailto:[email protected]>> wrote: All, In reviewing IEC 62368-1 Clause 5.4.9.1 the test procedure states about halfway down the page: "The insulation is subjected to the highest test voltage as follows: - by applying an a.c. voltage of substantially sine-wave form having a frequency of 50 Hz or 60 Hz; or - by applying a d.c. voltage in one polarity for the time specified below and then repeat it in the reverse polarity." Is anyone aware of a piece of test equipment that is capable of providing both polarities for the DC test on the high voltage output automatically or under software control? The equipment we have in our lab only provides a single polarity, positive with respect to ground when in DC mode, which requires us to manually reverse the leads to perform the test. We would like to automate this without requiring the operator to manipulate the test leads. We also do not want an operator to be involved in reversing the leads if we need to perform this as a routine test in manufacturing. Response here or off-line would be greatly appreciated. Gregory H. McClure Lexmark Product Safety 859 232 3240<tel:859%20232%203240> office 859 232 6882<tel:859%20232%206882> fax - ---------------------------------------------------------------- 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]<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 e-mail may contain privileged or confidential information. If you are not the intended recipient: (1) you may not disclose, use, distribute, copy or rely upon this message or attachment(s); and (2) please notify the sender by reply e-mail, and then delete this message and its attachment(s). Underwriters Laboratories Inc. and its affiliates disclaim all liability for any errors, omissions, corruption or virus in this message or any attachments. - ---------------------------------------------------------------- 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]>

