This is an old revision of this page, as edited by FrederikVds (talk | contribs) at 03:59, 26 June 2011 (→Standardization). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
Revision as of 03:59, 26 June 2011 by FrederikVds (talk | contribs) (→Standardization)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff) | Energy List‑class Mid‑importance | |||||||||
| ||||||||||
| This is the talk page for discussing improvements to the Mains electricity by country article. This is not a forum for general discussion of the article's subject. |
|
| Find sources: Google (books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
Archives: 1, 2, 3, 4, 5Auto-archiving period: 3 months  |
 Archives | |||||
|
|||||
|
This page has archives. Sections older than 90 days may be automatically archived by Lowercase sigmabot III when more than 8 sections are present. |
United States
The current US standard is 120v but older books often quote 117, 115 or even 110v) when/why did the US standardise on 120 volts. What was the situation prior to this (various standards in different states ???) and dd the change to 120v cause difficulties for those using older equipment ? 86.112.87.162 (talk) 15:27, 24 December 2010 (UTC)
What's better?
What's better? 50 Hertz or 60 Hertz, 110 Volts or 220 Volts? --Abdull 12:00, 22 July 2005 (UTC)
- 60Hz makes better use of the core material of transformers and motors compared to 50Hz so theorectically can be made smaller for the same kVA or kW rating - AC on aircraft (where weight is a priority) is 400Hz for this reason... On the other hand the higher 60Hz frequency will lead to slightly higher reactive loss on long cable runs compared to 50Hz... Much of a muchness really... With transformers being in the high 90's percentage efficiency-wise voltage isn't really the issue but more likely the current in household or industrial wiring... For a given power rating, lower voltage goes with higher current and so wiring has to be a thicker gauge = more copper = more cost... The difference isn't a lot though in a typical situation.. Anthrass 11:08, 16 January 2007 (UTC)
As I understand it, the US had better silicon steel for transformers, that worked well up to 60Hz, when Europe (at the time) had transformer steel that worked better at 50Hz. Otherwise, it requires less core material for a given transformer rating at higher frequency. Gah4 (talk) 00:24, 26 June 2009 (UTC)
- 230 Volts is overall better than 110 Volts because when using an apliance with a certain power consumption (say 100 Watts), the Amperage on a 230 Volts line wil be lower than on a 110 Volts line (as P(Watt) = U(Volts) * I(Ampère)). And Amps are lost over longer cable lengths, that's the reason why backbone power lines use 400.000 Volts with a relatively low Amperage. Also, the lower the Voltage, the thicker the cable needs to be (with the same power consumtion (Watt)). That's why modern cars run on 12V (old cars ran at 6V) and trucks on 24V (cables are longer there and Amps get lost over cable length). Rick2910 (talk) 20:09, 7 December 2008 (UTC)
- Actually, amperes are conserved in a wire; voltage drops.
- In places with 220 V mains, the electrical supply is much more likely to burn or electrocute you if you get across it, so they tend to have more elaborate safety measures on their plugs. The higher voltage uses wiring more efficiently, but makes it harder to make a good low-wattage incandescent bulb. Neither is better, the just have different properties. Dicklyon (talk) 00:55, 26 January 2009 (UTC)
- Any voltage above 42V is potentially deadly. Rick2910 (talk) 10:19, 30 January 2009 (UTC)
- Higher voltage is more efficient for transformers. As an example computer power supplies tend to be around 2% more efficient at 230V than 110V. 83.231.208.161 (talk) 15:46, 21 February 2009 (UTC)
The usual computer power supply converts either 120VAC or 240VAC to 300VDC, then through a switch transistor at about 20kHz and into a ferrite core transformer. The higher voltage is probably a little more efficient due to not needing the voltage doubler, but it isn't because of the transformer. In many cases 220VAC does allow for more efficient systems, especially for fluorescent lamps. For industrial use, 277VAC is common for lamps, phase to ground off a 480VAC three phase system. Lower voltages often work better for incandescent lamps, though. Gah4 (talk) 00:24, 26 June 2009 (UTC)
Saudia Arabia
I got few devices from saudia arabia configured on 110V (i burnt them using 220)
(they had only 2 options 110V or 220V) that is why i think they use 110V there
الثاقب (WiseSabre| talk) 17:45, 21 October 2005 (UTC)
- possiblly i think in a lot of places it depends on who built/owns the place you are living in. BTW 220 and 240 are close enough that it is almost never a problem to use a 220V device on a 240V system or a 240V device on a 220V system.
When I was in Saudi recently I saw 110V and 230V and measured both 50Hz and 60Hz on 230V lines. Not surprisingly one piece of 110V equipment had been blown by a customer plugging it in to 230V. The electrics were pretty frightening in the hotels too! 83.231.208.161 (talk) 15:49, 21 February 2009 (UTC)
orfography check
I added info about russian electric standart, but not sure in in spelling, please check it. BTW, up to begin of 1980-s many of soviet home-technik was produced as dual-standart - 127/220. I don't now about other xUSSR countries, but in Russia this standart using now in some isolated peripherial electric nets, just an example in some siberian villages. This standart uses same GOST plug as 220V.
Saudi Arabia
I'm still confused about Saudi Arabia. I've never been there, so I don't have any first-hand experience, but all the websites I've found about Saudi Arabia say that both 127 and 220 volts are used. But they don't say why both voltages are used. I mean, is it like half of the country uses 127 volts and the other half of the country uses 220 volts, or is the whole country in a transition period from 127 to 220 volts? Also, about the plugs and outlets there, for 127 volts, everything I've read so far say that it's usually A but sometimes B. But for 220 volts, some websites say it's F but other websites say that it's G, and some websites say that it's both F and G. Which is correct?
Marknagel 17:08, 21 April 2007 (UTC)
- The split voltages are partly so that they can run both US and European appliances. The plugs vary from building to building. I saw pretty much everything there and in some public buildings the sockets are all labelled so you've got some idea what might come out of them. Interestingly there were quite a lot of UK plugs used for important appliances so that weaker circuits couldn't be overloaded. 83.231.208.161 (talk) 15:53, 21 February 2009 (UTC)
China Outlet
I took a picture of a China outlet during my last trip. I can email to anyone would like to post it in this section.
Tahiti
All the tourist Web sites and "Electricity Abroad" says Tahiti is 60 Hz - you'd expect a French colony to be 50 Hz, but seems to be not the case. Anyone changing this, should have a good reference handy. --Wtshymanski (talk) 00:32, 8 August 2008 (UTC)
- I agree that the old 220v 50Hz French system is probable the official voltage system. This however may have been a local service around the main French administration town only . The GDP and annul earnings per capita and very small population -would I think- have made the building of a 'grid' as such, totally uneconomic (see the population growth figures for Tahiti#Historical_population). So what I think may have happened, is that as tourism took off, the major hotels chains found themselves free to create their own private (and more dependable) power systems, using what ever standard, their target clientèle would find the most familiar. The thought came to me that people who make money from selling adaptor might be the best informed. So, I found this adaptor supplierhttp://www.international-electrical-supplies.com/tahiti-plug-adapters.html According to them, some plug types are missing from the WP Tahiti entry.
- For the above reasons I don't think a WP suitable reference(s) will ever be forth coming. Maybe we should just say that the 220 50Hz is the standard supply -with tourist resorts having their own private systems of 110 or 120 @ 60hz or 240v @ 50Hz.--Aspro (talk) 11:42, 18 December 2008 (UTC)
- Nonsense...there's got to be a tourist guide or something printed. I wonder if the Tahiti electrical supply company has a Web site. My high-school French might be just enough to puzzle it out. --Wtshymanski (talk) 18:27, 20 December 2008 (UTC)
- The International Electrotechnical Commission (IEC) has zoned Haiti as 110v @ 60Hz plug type A & 1..http://www.iec.ch/zone/plugsocket/ps_america.htmSo that looks like the official voltage class now.--Aspro (talk) 14:32, 20 December 2008 (UTC)
- But Tahiti is on the other side of the earth - there's no listing on that page for Tahiti. --Wtshymanski (talk) 18:27, 20 December 2008 (UTC)
- Hmm. Now says 220 volts and 60 (sixty!) Hz, as does the Google Books snapshot at
And says 220 Volts but doesn't give frequency. --Wtshymanski (talk) 18:41, 20 December 2008 (UTC)
- Hey, the says 60 Hz. My rudimentary French lets me think their history of 60 Hz generation goes back to WWII, when they imported a lot of US-spec equipment, even though they had a hydro plant in 1911. --Wtshymanski (talk) 19:04, 20 December 2008 (UTC)
New Discussion
A discussion has been started at Misplaced Pages talk:WikiProject Countries/Lists of countries which could affect the inclusion criteria and title of this and other lists of countries. Editors are invited to participate. Pfainuk talk 12:06, 17 December 2008 (UTC)
- This article has a list of "regions", not "countries", which side-steps the issue; for the purposes of this articlea "region" could probably be defined as the geographically contiguous largest political unit with a uniform system of electrical plugs and power. Over-refining this definition, for this article anyway, doesn't seem to me to be a good use of human effort. --Wtshymanski (talk) 15:04, 17 December 2008 (UTC)
- Fair enough. I'm not trying to force anything on any article where it is more appropriate to use something else. Pfainuk talk 17:20, 17 December 2008 (UTC)
- I find it's often very useful to think about what a definition will be used for, before getting too worked up about definitions. --Wtshymanski (talk) 01:50, 18 December 2008 (UTC)
- Fair enough. I'm not trying to force anything on any article where it is more appropriate to use something else. Pfainuk talk 17:20, 17 December 2008 (UTC)
Move?
Shouldn't this article be moved to mains electricity systems ? —Preceding unsigned comment added by 81.245.188.21 (talk)
- Doesn't need to be, since it's mostly an international table of standards that can stand on it's own rather than make the other article look more larger (it's already wikilinked to it anyways). Also the other article is name Mains electricity... minus the systems (unless you meant the sub-topic there). That-Vela-Fella (talk) 19:40, 6 May 2009 (UTC)
Title/Links Limitations
Being from Canada, where the word 'mains' is not in general usage, I had a lot of trouble finding this article which includes the list I was looking for. My first search was 'electrical systems' which gave me nothing (though I have since noted that 'electrical system' (sans 's') redirects to 'electricity' - an article that I don't believe has a link to this one. I noticed that the first External Link listed here includes the phrase 'electrical systems'. I will be bold and try to set up a redirect for 'electrical systems' to this page and maybe add a link in the electricity page if it's not there. I notice that in the 'Lists of Countries' entry that redirects here also includes 'mains'. I am not suggesting that the word should be changed but wonder if anyone has suggestions on making the titles more globally accessible. I like the phrase used in the first line of this article - 'list of countries and territories, with the plugs, voltages and frequencies' --Yickbob (talk) 12:11, 2 June 2009 (UTC)
- I made the changes but now wonder if the redirect of 'electrical systems' to this page, while great for non-experts like me, would be deemed scientifically incorrect. I know there is an area of study called 'electrical systems' as well. Any feedback? --Yickbob (talk) 13:30, 2 June 2009 (UTC)
Type I socket (Australia/New Zealand)
The illustration of a type I socket has a very unusual indentation around the pin apertures... that socket doesn't comply with the current standards. New photo? —Preceding unsigned comment added by 203.167.186.239 (talk) 02:02, 9 August 2009 (UTC)
The indentation you see around the earth pin is just a cosmetic design. Some manufacturers make receptacles with flat faces. Others add slight indentations around the pin holes in order to help locate them when fumbling around in the dark. The same issue applies to USA type (A & B) receptacles. Stephanie Weil (talk) 20:03, 26 October 2010 (UTC)
References
It would be a lot easier to protect this article from vandalism if people would provide references. Granted, English-language references for historical Greek wall plugs (for example) are going to be *rare* but nobody ever cites a reference for anything in this article! --Wtshymanski (talk) 02:41, 13 December 2009 (UTC)
- The "Rough Guide" series looks promising. --Wtshymanski (talk) 14:18, 13 January 2011 (UTC)
Vector maps
Since the switch to the vector maps was recently undone by an anonymous user without comments I want to give reasons for their use here.
Both, the map showing the plug types in use and the map showing the mains frequencies and voltages have been created to exceed not only the visual quality of the old raster maps, but also to better do their actual job, i.e. presenting the respective pieces of information in a sensible way. This includes the following:
- Recreation using information from the most recent tables from the German and the English Misplaced Pages articles
- Disambiguation concerning incompatible plug/socket standards the old map used a single color for, so e.g.
- French and German plugs/sockets (mechanically incompatible)
- French and Russian plugs/sockets (see above)
- German and Russian plugs/sockets (partially incompatible due to different pin width)
- Marking C-only-countries (missing grounding → electrically incompatible)
- Correctly naming the Russian standard (GOST 7396)
- Distinguish between type A and type B sockets (B plugs won't fit into an A socket)
- including the IEC 60906 plugs/sockets being introduced in Brazil
Voltage/Frequency map:
- Different shades of the colors for slightly differing voltages (approx. 220, 230, 240 volts or 110, 120 or 127 volts)
I hope any further removal of these maps in favor of the old ones includes equally good reasons. (By the way, in case you find mistakes in one of the maps you can always use my discussion page.) SomnusDe (talk) 20:42, 6 February 2010 (UTC)
- I think the standard (at least in practice) in Russia and its post-Soviet neighbors such as Belarus and Ukraine is the same. Essentially it is type C so no need for special color for Soviet GOST.--MathFacts (talk) 14:47, 25 March 2010 (UTC)
- Important question: What is the pin-diameter? 4,8mm or 4,0mm? If it is 4,8mm most European plugs will fit, if not, possibly only the flat europlug will fit. And is there any grounding? PS: If you (or anyone else) come(s) from one of the mentioned countries, please let us all know. Statements from inhabitants always have some special weight. --SomnusDe (talk) 11:49, 8 April 2010 (UTC)
- Traditionally (since Soviet times) 4 mm without grounding (i.e. type C with socket essentially the same as Europlug). Now there can occur different variants to accommodate Schuko-style European plugs.--MathFacts (talk) 16:21, 11 April 2010 (UTC)
- Important question: What is the pin-diameter? 4,8mm or 4,0mm? If it is 4,8mm most European plugs will fit, if not, possibly only the flat europlug will fit. And is there any grounding? PS: If you (or anyone else) come(s) from one of the mentioned countries, please let us all know. Statements from inhabitants always have some special weight. --SomnusDe (talk) 11:49, 8 April 2010 (UTC)
Corfu (Kerkyra) is not a country - remove from table
I cannot edit the page directly because it is protected. Somebody please remove Corfu (Kerkyra) from the Table of mains voltages and frequencies. This island is just a part of Greece and the table entry for Greece applies to it as well. Thanks in advance. —Preceding unsigned comment added by 193.136.60.48 (talk) 15:31, 24 March 2011 (UTC)
- Not done. See "new discussion" above. The list is of countries and "territories" precisely so we can preempt the endless wikiwrangling about who is legally allowed to collect taxes on which plot of dirt. --Wtshymanski (talk) 14:12, 20 May 2011 (UTC)
Standardization
I think it's notable that I can draw a 3000 km radius around my home city and be highly confident that for any hotel I stay at within that radius, my appliances will fit the wall plug - and it's been that way for my lifetime. Is there any other (populated) region on Earth that can make that claim? If you draw a 3000 km radius around, oh, say, Amsterdam, how many different sockets will you encounter in that radius? (Shucks, even a 3000 km radius around the South Pole will give you different plugs at the American base, the Norwegian base, the Russian base, the Australian base, the New Zealand base...etc.) --Wtshymanski (talk) 13:51, 20 May 2011 (UTC)
- I agree. Same plugs and sockets, same Holiday Inns, same TV repeats, same McDonald's, same hire cars, etc., etc., etc. Kind of takes all the fun out of going somewhere different. Both notable and boring. Might as well stayed at home and painted the fence.--Aspro (talk) 18:09, 20 May 2011 (UTC)
- Sorry, but I removed the "while standardized in North America" remark. There are other areas that are standardized as well, like most of mainland Europe. There is nothing special about the situation in North America, it's only two countries that happen to use the same wall plug. Yes, geographically it's a large area, but it's quite sparsely populated compared to e.g. Europe.
- About this: "300,000,000 consumers don't have to pack adapters when they travel, unlike most parts of the world...sure it counts". That depends of course where you travel to! I don't have to pack adapters most of the time, unless for a few specific countries like the UK (or the US). You have to pack an adapter for any country you travel to except for Canada or the United States. --FrederikVds (talk) 01:23, 23 June 2011 (UTC)
- I think it's sweet that the Europeans can all agree on using the same currency and *still* can't agree on a wall plug. --Wtshymanski (talk) 01:13, 24 June 2011 (UTC)
- Changing wall plugs is harder than changing currency. Currency isn't fixed to the walls of your house. Anyway, most of the European Union (and a lot of other European and Asian countries as well) has standardized on the C/E/F type. The only difference among those is the presence and location of the grounding connection, but they are compatible. So only two kinds of plugs, the C type for appliances that don't need a ground, and the E+F type for all others, are sold in Europe. No travel connector required.
- Please, before reverting my edit again, provide evidence for your claim that the North American situation is exceptional or noteworthy. Maybe you could move it to a different section with all standardisation efforts around the world mentioned. But the current claim, that "voltage, frequency, and wall socket type, while standardized in North America, vary widely in the rest of the world", focuses on one example of standardisation, while there are many.--FrederikVds (talk) 19:22, 24 June 2011 (UTC)
- See above. Draw a 3000 km radius circle centered on any city and count the number of different receptacles used within that radius. North America is unique in the world. We're talking about wall plugs, voltage and frequency here. European seem to somewhat agree on frequency, have varying opinions on voltage, and can't travel 1000 km without changing plugs. It's different. --Wtshymanski (talk) 21:42, 24 June 2011 (UTC)
- All of Europe uses the same frequency (exactly the same, of course, or we wouldn't be able to transfer power between countries). All of the European Union uses the same nominal voltage. And I just checked, and all electrical equipment I can find in my house uses either C or E+F plugs, so I can take it to eastern Russia, a few hundred kilometres from western Canada, or to Iceland, almost the other side of the Northern hemisphere, and almost all places in between. So your claim that I can't travel 1000 km without changing plugs is just incorrect.
- As to your thought exercise, let's take Canberra. In a 3000 km radius, only one kind of wall plug. But even if North America was unique in that regard, every country is unique under some arbitrary criterion. Find a standard agreed to by more than 20 countries. Find a geographically contiguous region where more than 500 million people use compatible equipment.
- Canada is just a smaller country (in terms of population) that uses the same standard as the neighbouring larger country. You can see the same thing happening all over the world. I don't think it's noteworthy just because of an arbitrary criterion of size.--FrederikVds (talk) 22:23, 24 June 2011 (UTC)
- Sorry for being so insistent about this, by the way. It's just that I read that sentence and expected that maybe North America followed some international standard that others ignored. But, as far as I know, that's not the case. It really confused me, and will probably confuse others as well.--FrederikVds (talk) 00:53, 25 June 2011 (UTC)
- See above. Draw a 3000 km radius circle centered on any city and count the number of different receptacles used within that radius. North America is unique in the world. We're talking about wall plugs, voltage and frequency here. European seem to somewhat agree on frequency, have varying opinions on voltage, and can't travel 1000 km without changing plugs. It's different. --Wtshymanski (talk) 21:42, 24 June 2011 (UTC)
- I think it's sweet that the Europeans can all agree on using the same currency and *still* can't agree on a wall plug. --Wtshymanski (talk) 01:13, 24 June 2011 (UTC)
No need to be sorry, this is how the encyclopedia grows. According to our table, Australia (and NZ and PNG) uses type I. Indonesia uses C,F, G. (Not much of Indonesia within the 3000 km radius, but Merauke probably has some outlets). New Calendonia uses type E (and a New Zealand travel Web site warns Kiwis to pack an adapter). Not as much a problem for someone who's already facing a long flight, but in North America we can can be more carefree in our cross-border jaunts.) And all three countries within the 3000 km radius of my home are members of IEC and other international standards organizations. Bully for European colonialism. Your serve. --Wtshymanski (talk) 14:14, 25 June 2011 (UTC)
- OK, I forgot about some islands that are just inside the 3000 km radius. And I don't know where you live, so I can't check, but Saint Pierre and Miquelon must at least be very close to 3000 km away. And about Australia being "uninhabited": of all other continents, only Antarctica is less populous than North America. (Depending on your definition of a continent, North America may include Mexico and Central America. Then South America has a smaller population, but of course North America isn't standardised any more.)
- That's not the point, though. The 3000 km radius thing is still completely arbitrary. You would have to prove that a radius of 3000 km is more noteworthy than other criteria (like a large population using the same standard). Saying "standardized in North America" implies that there is much more to it than just two or three countries that use the same standard. Even if those countries are quite big.--FrederikVds (talk) 14:52, 25 June 2011 (UTC)
- Also, please stop reverting the article before responding here, like you just did again.--FrederikVds (talk) 15:04, 25 June 2011 (UTC)
- Could you respond? You have reverted my change to the main article since my last comment here. If you don't respond within a few hours, I'm reverting it to my version again. I don't want this to become an edit war, but it seems like you only ever respond after a change to the main article.--FrederikVds (talk) 16:54, 25 June 2011 (UTC)
- I changed it to my version, as there still is no explanation for your last revert...--FrederikVds (talk) 23:54, 25 June 2011 (UTC)
- My response was in the edit comment - not having anything new to say, I referred to the discussion above. 3000 km radius is in not in the article and so doesn't need a citation. --Wtshymanski (talk) 03:34, 26 June 2011 (UTC)
- Even I have things to do other than edit Misplaced Pages. Ultimatums are un-necessary. --Wtshymanski (talk) 03:47, 26 June 2011 (UTC)
- I refuted your points. If you think I didn't, you should specify why. If you have "nothing new to say", that means there is no reason for the article to stay as you want it to be.
- I'm not asking for a citation, but the whole reason why you want this to be in the article is because you "think it's notable that I can draw a 3000 km radius around my home city and be highly confident that for any hotel I stay at within that radius, my appliances will fit the wall plug". Why is that notable? It's not directly applicable here, but just because something is true, doesn't mean it's notable. I can travel to dozens of countries and my plugs will fit. You can't just say that is less notable because they don't completely fill a circle with 3000 km radius. There just isn't any reason to say that the US or Canada is any less or more standardised than any other country.
- I'm going to make the (hopefully final) change to the article. Please don't just revert it again without an actual argumentation. Misplaced Pages is built on civil discussion and consensus, not edit warring.--FrederikVds (talk) 03:55, 26 June 2011 (UTC)
- And ultimatums are sometimes necessary. You reverted my edit without giving any reason on the talk page or the edit summary. I'm not going to wait indefinitely until you have time to respond. If you don't have time to respond immediately, just leave the article as it is until you do!--FrederikVds (talk) 03:59, 26 June 2011 (UTC)
Misinterpretation of Europe wide 230 volt systems.
The table gives us many mainland European countries as being 230 volts (formerly 220 volts). The table also gives the United Kingdom as 230 volt (formerly 240 volts). Actually neither is correct. Indeed the notes column does point out that the UK remains centered on 240 volts (though fails to mention similar for other European countries). The reality is that mainland Europe always has been, still is and is intended to be for the forseeable future, 220 volts. Similarly, the UK is 240 volts and there is no intention of changing this. What has changed, is that all of Europe is now nominally 230 volts with the tolerances widened to encompass the individual countries' voltages. The nominal voltage is (since 2008) 230 volts ±10% (i.e. more or less 207 volts to 253 volts). Both mainland 220 volts and UK 240 volts fall within this tolerance.
The actual voltage and tolerance sepecified for the individual countries reflects this. For example the standard UK voltage is specified as 240 volts -14% +6% and mainland Europe is specified as 220 volts -6% +15%. The actual voltage is further betrayed by the fact that filament lamps (the few that are left!) sold in the UK are rated at 240 volts, and those sold in mainland Europe are 220 volt. The intended effect of the change is that nearly all appliances (except voltage sensitive items such as filament lamps) shall be capable of operating over the full 207 to 253 volt range. There are a few areas of the UK that are actually 250 volts (mainly some suburbs of some principal cities) but fortunately these fall within the tolerance band even though the upper tolerance is quite tight at just 1%. There are also still a few genuine 230 volt areas that have hung around since AC systems were first installed (including some that are a 115-0-115 volt split systems) but they couldn't possibly have known about the EU harmonisation when they were installed. 86.182.103.115 (talk) 16:52, 10 June 2011 (UTC)
- I agree. The confusion appears to come about from confusing the electrical standards with the voltage supplied in different countries. Having the same standard across Europe obviously has the advantage in that equipment data sheets can be standardised. Also, equipment manufactured to this new standard can be more easily traded across boarders. What might help is to add a new column that states the name of the voltage standard for supply and 'declared nominal' and the existing column for the real centre or average rms voltage . Even 110 systems comply to different standards in different countries – although they are quickly coming into line with each other. Comment: A 250 v readings will usually only mean that one is very close to the substation. I've only ever seen split voltage systems (UK) in places such as milking parlours and abattoirs, were one wants to reduce the chance of lethal electric shock on wet floors. --Aspro (talk) 17:47, 10 June 2011 (UTC)