Hi Brian:
If your charger is powered from 120/240 volts domestic service, the maximum transient over-voltage is about 6 kV due to the clearances in the service entrance. Domestic equipment will never see 15 kV. Likewise, for industrial service, the maximum transient over-voltage will be determined by the clearances in the service entrance, and not likely as high as 15 kV (18 mm according to IEC 60664-1, Table F.2). So, it appears to me that your charger is to be connected to an unprotected overhead service that is subject to lightning strikes up to 15 kV. Suppression is difficult. But, you said "pass," not suppress. Easier, but takes lots of space - 18 mm between all conductors. And some good, HV solid insulation. Did your customer specify expected energy? You might do a Google search for 15 kV surge arrester. Best regards, Rich From: Brian Ceresney [mailto:bceres...@delta-q.com] Sent: Tuesday, August 22, 2017 9:39 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Surge Suppression - Dos, and Don'ts We have been requested to pass 15kV on the mains input. Best Regards, Brian C. From: James Pawson (U3C) [ <mailto:ja...@unit3compliance.co.uk> mailto:ja...@unit3compliance.co.uk] Sent: August-22-17 9:36 AM To: Brian Ceresney < <mailto:bceres...@delta-q.com> bceres...@delta-q.com>; <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] Surge Suppression - Dos, and Don'ts Hello Brian, What surge voltages are you testing to? Presumably just on the mains input? Thanks James From: Brian Ceresney [ <mailto:bceres...@delta-q.com> mailto:bceres...@delta-q.com] Sent: 22 August 2017 17:31 To: <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Surge Suppression - Dos, and Don'ts Dear Regulatory Experts, We have recently had a request from a customer to modify an industrial battery charger(48V, 1000W output) to meet extremely high surge limits, ostensibly to help survive lightning strikes. In designing this version of the product, we have added varistor surge protection from Line-Ground, Line-Line, and Neutral-Ground positions. This product is intended for use in North America, and Europe, and will be third-party-approved for both. I recall from previous discussions on this forum that there are specific requirements for accepting this type of design, due to the inevitable failure of the surge protection devices. I believe that fuse protection in line with each surge device is required, as well as some sort of indication to warn the user when the surge protection circuitry is damaged. Series connected spark -gap devices were mentioned, and there was also some discussion about the rationale behind dielectric strength testing, and how to perform it, especially on the production line. I've searched the archives, but not found anything definitive that is recent. In addition, even though Google is my friend, I have not managed to find a standard that can offer me up to date guidance on this issue. Can anyone suggest standards, bulletins, or any other document that can light my way? Thanks, in advance, Best Regards, Brian (the third Brian, I think) _____ Brian Ceresney Regulatory Lead Delta-Q Technologies Corp. 3755 Willingdon Avenue, Burnaby, B.C. Canada. V5G 3H3 - ---------------------------------------------------------------- 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 <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
