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Hi Ron I am aware, in a conventional system, that the phase to neutral voltage is 120V and the phase to phase voltage is 208V. What I do not understand is that this system is claimed to have 120V to neutral and there is also a line that gives 208V to neutral (verified by measurement). I have been told that it is a four wire system (3 phases and neutral) and two lines are at 120V and one is at 208V. Perhaps there is another line that my friend has missed. Belize is one of those countries where several voltages are used. I am interested to see if anyone can shed any light on this connection type. Thanks John From: Ronald R. Wellman [mailto:[email protected]] Sent: 26 July 2004 13:46 To: [email protected]; EMC-PSTC (E-mail) Subject: Re: Three Phase Power in Belize Hello John, A 120V/208V system is configured off a wye transformer. You measure 120V >from each phase to neutral at 0, 120, and 240 degrees. Phase-to-phase voltages are 208V. The neutral is the center of the wye and is normally referenced to earth ground. If you need to know why the voltage is 208 from phase-to-phase, you can prove this mathematically using phasors. Best regards, Ron Wellman At 03:44 AM 7/26/2004, John McAuley wrote: >http://www.ieee-pses.org/symposium > http://www.emc2004.org/ >-------------------------------------------------- > >Dear Group > >A friend of mine is doing development/charity work in Belize and is trying >to hook up some old lathes, milling machines etc of European origin to their >supply. He has limited electrical knowledge being from a mechanical >background. He tells me that the supply is "high line". Apparently this >means that they have two phases at 120 V and a third line at 208 V!! >Apparently there are 3 phase machines already running on this supply. He has >measured the phase voltages and has confirmed the levels. The machines were >rewired for a 120V/208V system. > >Is anyone familiar with this connection system? Is there a voltage offset on >the neutral? I can't find reference to it on the internet. I would like to >be in a position to teach him how the identify the phase voltages so that he >can connect up the machines without generating any more smoke. > >Many Thanks > >John McAuley > >------------------------------------------- > >This message is from the IEEE Product Safety Engineering Society >emc-pstc discussion list. > >IEEE PSES Main Website: http://www.ieee-pses.org/ > >To post a message send your e-mail to [email protected] > >Instructions for use of the list server: > > 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: > > Ron Pickard: [email protected] > Dave Heald: [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 This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. IEEE PSES Main Website: http://www.ieee-pses.org/ To post a message send your e-mail to [email protected] Instructions for use of the list server: 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: Ron Pickard: [email protected] Dave Heald: [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
