hi Allan, One fact that might be useful to consider is that a three phase supply has 3 hot/live/active wires and one neutral. The 3 currents returning to the neutral actually cancel each other out (due to phase differences) and in a perfectly balanced load situation there is no need for a neutral, but where a number of diverse circuits are connected there will be some imbalance, so you need a wire there, but it need not be as heavy as the 3 “hot" ones.
cheers Hugh Hugh Piggott Scoraig Wind Electric Dundonnell Ross shire IV23 2RE, UK +44 77 1315 7600 h...@scoraigwind.co.uk www.scoraigwind.co.uk <http://www.scoraigwind.co.uk/> > On 26 Nov 2016, at 01:27, Allan Sindelar <al...@sindelarsolar.com> wrote: > > Wrenches, > Is there such a thing as a "grid neutral"? I have been providing design > support to a client for a large off grid system; a prepper, rare in these > parts. He claims that utility current is carried in part through the ground > and in part through a neutral conductor, and such a "utility neutral" is > deliberately undersized. At first I pushed back (see below). Now I just > wonder what Wrenches more knowledgeable than I am will say. > Thank you, > Allan > > Allan Sindelar > al...@sindelarsolar.com <mailto:al...@sindelarsolar.com> > NABCEP Certified PV Installation Professional > NABCEP Certified Technical Sales Professional > New Mexico EE98J Journeyman Electrician > Founder (Retired), Positive Energy, Inc. > 505 780-2738 cell > > -------- Forwarded Message -------- > Date: Thu, 24 Nov 2016 11:25:36 -0700 > > Allan > Happy thanksgiving. Sorry for the slow reply; overwhelmed here. > > All wet sorry. If you look at the power lines you will see two or three wires > at top of pole and the one smaller one a little ways down the pole. This is > the power station neutral. > > The hots bidirectional is an explanation that helps people understand current > but is not totally clear. > Even if you use that visualization in order for the electrons on the hot to > oscillate they heed a path to oscillate into and out of > That is the “neutral”. > > Bottom line is from the power station and in your home you have at least one > hot and one neutral. > You can actually use the hot to light up a lite bulb by connecting the other > side of the lite bulb to the earth. > This one way you can get electrocuted. > I touched the hot side of a 220 circuit and the current went thru me and into > the earth…not much fun. > > This has been openly publicly discussed and one of the electrical association > advised the power companies to increase the size of the neutral to solve many > issues, such as cows giving less milk and problems with electric current in > homes. The power companies even openly discuss this. > > In remote rural areas of Australia, I have seen electricity distribution > using SWER (Single-Wire Earth Return); just one wire is fed to the property > at a high voltage, with the current returning via the ground. At the > property, a transformer turns the high voltage into normal residential > voltages on a pair of wires (230VAC in Australia vs 2x115V in some other > countries). But this SWER system is inefficient, and the supply voltage is > poorly regulated; it is a rare exception - it is only done because of the > high cost of delivering two wires in remote areas. > > In metropolitan areas, you will typically see 4 wires passing down the > street. This consists of three phases of "Active", plus a "Neutral". You > could imagine the Active carrying current "from" the power grid, and the > Neutral carrying the current "back to" the power grid (even though the > current flow is symmetrical). > > There is lots of info online if you wish to learn more about this. > Take care, Robert > > From: Allan Sindelar [mailto:al...@sindelarsolar.com > <mailto:al...@sindelarsolar.com>] > Sent: Sunday, October 23, 2016 10:18 PM > > Robert, > I'm neither an electrical engineer or a utility employee, so I may be all wet > here, and if so please dry me off with a straight-up explanation. But this > whole argument seems specious to me, as it addresses a "grid neutral". > > My reasoning is this - there is no such animal as a "grid neutral" in utility > lines, so how is this issue even relevant? The "hots" are bidirectional; only > when the utility power is stepped down at the transformer at the home is a > reference neutral created. To say that the current "cannot all go back thru > the neutral since it is not large enough BY DESIGN" seems to me an absurd > concept since there is no neutral in utility power distribution. > > Am I missing something? > Allan > > On 10/2/2016 7:51 PM, Robert wrote: > Allan > Here is the info I said I would send: > https://www.youtube.com/watch?v=aJOB2FIqUiQ > <https://www.youtube.com/watch?v=aJOB2FIqUiQ>. Listen about 20 minutes at > least. > > All current that goes “out” on the two residential or three commercial hots > goes back on the grid neutral > AND thru the ground'. It cannot all go back thru the neutral since it is not > large enough BY DESIGN. So…. That means we really don’t have a clean ground > anymore. > > Thank you for your time today. It is enjoyable to speak with you. > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: RE-wrenches@lists.re-wrenches.org > <mailto:RE-wrenches@lists.re-wrenches.org> > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> > > List-Archive: > http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html > <http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html> > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> > > Check out or update participant bios: > www.members.re-wrenches.org <http://www.members.re-wrenches.org/> >
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