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Joined: Aug 2001
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Hi Elektroinstalacje, and welcome to the forum. ![[Linked Image]](https://www.electrical-contractor.net/ubb/smile.gif) There are many different voltage levels used throughout the U.S., more than in most countries due to the sheer size of the nation and the various electricity companies there. Even at the low-voltage end of the scale there are several different systems: 120/240V 3-wire, 120/208V 3-phase, 277/480V 3-phase, 240V delta, etc. I remember somebody posted a link to a document from Cooper Transformers a year or two ago which provided a pretty good explanation of some of the different HV systems in use. Can anyone remember the link? Over here in Britain, our most common voltage levels are 240V 1-ph or 240/415V 3-phase, 11kV, 33kV, 66kV, 132kV, 275kV, and 400kV. There are still a few local distribution systems using 6.6kV, but these are quite rare now. There are other levels used for specific purposes, such as a high-voltage D.C. interconnection with France, 25kV A.C. for long-distance railways, etc. Here are a few photos: Typical 33kV line Typical 11kV line More 11kV local distribution Overhead to underground transition with switch, also 11kV Small pole xfmr on single-phase spur line Typical 3-phase pole transformer Same pole, showing secondary fuses Typical pad-mount xfmr in wooden enclosure All above transformers are 11kV primary, 240V or 240/415V secondary. Typical 240/415V overhead distribution lines (Poles in that last photo also have telephone lines lower down.) Single-phase xfmr feeding 240/480V 3-wire distribution in rural area All of the above are my own pics. Feel free to copy and use if you wish. For the larger transmission lines (132kV and upward), have a look at some of the photos on this site: http://users.tinyonline.co.uk/bigh/bigh/photoarchive.htm
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Joined: Sep 2005
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Hey pauluk1
I notice in your distribution pics there are only three conductors. Is your system a 3 wire delta rather than a 4 wire wye?
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Joined: Dec 2001
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In most European countries anything above 230/400V is 3w delta. Saves a lot of copper.
The transformers have a delta primary and wye secondary with grounded star point. (class DYN)
And Pauluk supplied some pictures of a System that only exists in the UK, NZ aud Australia (or maybe not even NZ) - 230/460V single phase AC.
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Joined: Aug 2001
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Yes, as TR says we don't distribute a neutral on any of our HV lines. They can be wye connected at source, but the neutral goes no farther than that. Thus even a single-phase spur line has to be run as two phases, as you can see in a couple of those photos.
The 1-ph 3-wire 240/480V arrangement (O.K., its 230/460 officially now) is found in rural areas where the xfmr has to serve a relatively small group of homes. All neighborhoods of any size are wired with 4-wire 240/415 (230/400) wye LV.
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Joined: Dec 2005
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As Texas_Ranger says not being sure we use 1 Phase 230 / 460 Volts in New Zealand. Yes we use it at the 2 phase 11 kV supplies and the 1 phase 11 kV SWER system. I will post some piccies later Elektroinstalacje search under Photos' , SWER in this forum and there are some SWER lines and transformers from NZ. https://www.electrical-contractor.net/ubb/Forum5/HTML/001143.html edited to insert link [This message has been edited by RODALCO (edited 02-06-2007).]
The product of rotation, excitation and flux produces electricty.
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Joined: Jul 2002
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Gidday there Elektroinstalacje, Welcome to ECN, mate!. ![[Linked Image]](https://www.electrical-contractor.net/ubb/wink.gif) Ray (RODALCO), I would add to that list of voltages, the now defunct, but still in use in some areas, 1.1kV system. It was used here in both Mid and South Canterbury, in particular in South Canterbury, when the old MED (Municipal Electricity Department) had the function of a utility in Timaru and places like that. 400/230V has all but super-ceded, this system, but remnants of it still do exist. It came about before the 400/230 system and was used as a means of a distribution system for light commercial/industrial, the primary side of the tranny being 1.1kV, the secondary being 3 phase 230 + neutral. Then a 600 kV DC link is between the North and the South Island. Ray, I thought that the DC link was 500kV, has this been bumped up as well?. If you do get the chance Ray, go to Benmore and see the rectifier banks that supply this link, I was down there a few years ago, it is an absolutely amazing experience. I would have taken pictures but I didn't own a digital camera at the time. ![[Linked Image]](https://www.electrical-contractor.net/ubb/frown.gif) The hum from that place is like being next to a humungous welder.
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Joined: Feb 2007
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The list of voltage is as long as my shopping list today Thanks everyone for answer. If you have some interesting pictures about this and want to share it witch electricians in Poland please write to me. I'll put them to my web album.
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Joined: Dec 2005
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Mike http://www.transpower.co.nz/?id=4798 It runs at 270 and 350 kV each leg. between two phases it is 620 kV dc.
The product of rotation, excitation and flux produces electricty.
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Posts: 22
Joined: August 2009
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