Carl, What is your input rating? If it is something like "Two (2) Lines: 230 V ac, 30 A, 1 ph, 50 Hz", then you have to run the neutral conductor to each of these inputs. It would not matter what phase conductors you connect. If the customer's three phase source is a delta instead of a star (wye), then they will have trouble, and will need to transform over to a star (wye). I don't believe that BS 7671 forbids two single-phase inputs at all. It is probably most important, as you say, that you communicate via labeling and rating exactly what mains input your product requires. Look at Table 51 in the latest addition of BS 7671 for identification of conductors. You could probably use any of the 3 phase conductor colours, or just brown for the phase conductors, but use blue for each of the neutrals. Best Regards,
Don Gies, N.C.E Senior Product Compliance Engineer Lucent Technologies Holmdel, NJ 07733 USA From: Richards, Carl [mailto:[email protected]] Sent: Thursday, September 29, 2005 9:56 AM To: [email protected] Subject: Mixing of Power phases - Legal position Dear all, This is a question aimed at the UK market - although any continental input appreciated. We have a customer who wishes to power our product via two 30A Single Phase spurs, the customer has two Power Distribution Units (PDU's) each with 3 phase supplies. The customer wishes to provide a single phase from each PDU to ensure power balancing and outage protection, but it seems cannot guarantee that we will get the same phase colour from each PDU. Brushing to one side for a moment the technical issues, and the possible frightening consequences; what does the IEE Regs have to say about such a scenario ? I have a condensed version which make no mention as far as I can tell about this kind of situation, clearly we will be demanding that our cabinets are clearly marked and the cable presentation reflects the final power installation to reduce the possibility of accidents during servicing. If anyone has any advice it would be gratefully received. All the best Carl Carl Richards, Regulatory Compliance Manager, Aspect Software 2, The Square Stockley Park, Uxbridge, UB11 1AD, United Kingdom +44 (0)208 589 1461 Office +44 (0)870 460 1950 Fax +44 (0)7875 27 1461 Mobile www.aspect.com <http://www.aspect.com/> - 2005 IEEE Symposium on Product Safety Engineering 3-4 October Schaumburg, IL http://www.ieee-pses.org/symposium ---------------------------------------------------------------- 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/listserv/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: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - 2005 IEEE Symposium on Product Safety Engineering 3-4 October Schaumburg, IL http://www.ieee-pses.org/symposium ---------------------------------------------------------------- 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/listserv/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
