Talk:Mains electricity by country

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Current ratings?[edit]

I notice from earlier entries archived from this page that a lot of effort has been expended arguing over the voltage rating of certain connectors, with the result that there is now a rather silly warning that is repeated over and over again in the table of mains voltages and frequencies, wasting space where a simple asterisk and footnote would surely suffice, while hardly any mention is made of the current rating of the connectors. By that, I mean that the current rating is given for some of the IEC standard range of plugs but no mention at all is given for the sockets found in the table. This seems topsy-turvey to me because it's the current that is dangerous, not the voltage, as anyone with a grasp of basic physics will understand. Drawing 10 A from a socket rated for 5 A will invariably be a greater risk than using a 125 V rated power cord with a 220 V supply. It would be naive to hope that all supplies would be protected from over current by the appropriate fuses or circuit breakers, and it is not often possible to check for oneself. (talk) 12:18, 18 January 2015 (UTC)

Sockets do not accept plugs with current ratings higher than the socket, this is a fundamental of standards and is a condition of IEC 60884-1. By contrast, some countries use versions of Type A and/or B sockets on supplies greater than the 125 V for which they were originally designed, and have supposedly tested those sockets at higher voltage. As these sockets will also accept plugs rated at only 125 V (in contravention of IEC 60884-1, para 9.2) it is important to draw that to the attention of readers, an asterisk and footnote would tend to imply that the information is of only secondary importance, which is not correct. FF-UK (talk) 17:25, 19 January 2015 (UTC)
It's safety advice and therefore it is of secondary importance in an encyclopedia. Furthermore it is uncited and appears to be original research. (talk) 20:07, 19 January 2015 (UTC)
The fact that "sockets do not accept plugs with current ratings higher than the socket" doesn't answer my point that the table contains no reference to socket current ratings. (talk) 14:37, 20 January 2015 (UTC)
The tables are about plugs and voltages, there is no specific information about sockets, therefore no mention of ratings. This may be because the primary reference source for this page is about plugs rather than sockets? It ought to be possible to add socket information where suitable references can be found, but there are currently only a few references to reliable sources other than the IEC World Plugs web pages, so this might be problematical?
I have added information about IEC 60884-1 to the article, with reference, and also an image of 125V rating markings on NEMA 5-15 plugs. I believe that 250V rated Type A and Type B plugs do exist (in contravention of IEC 60884-1) but have never seen any. FF-UK (talk) 19:29, 20 January 2015 (UTC)
Chinese standard GB 2099.1 Plugs and socket-outlets for household and similar purposes, Part 1: General requirements (2008) is available on Google Translate says the table in section 6 is "ratings" and the Google translation says there are 2-pole plugs rated 250 volt. Also, the diagram on page 94 of the .PDF shows a parallel-blade plug of the Type A shape. --Wtshymanski (talk) 01:13, 21 January 2015 (UTC)
I agree, and although there appear to be many mentions of IEC 60884-1 in that document I can not find the required statement about the non-compliance on voltage rating. It does not say much about the value of Chinese standards! FF-UK (talk) 00:38, 22 January 2015 (UTC)
The article is about mains electricity in different countries. Electricity is provided via a socket, therefore to be of relevance to the article the table should provide information about the sockets and the current rating is a very important factor. I agree that finding sources might be difficult. Regarding the comment about Type A and Type B plugs, I don't believe that the "Types" form any kind of standard but certainly flat-bladed plugs are used at voltages higher than the 125 V that those used in the USA are rated at. I have personal experience of mains sockets in the Philippines where this is the case. I wonder when the IEC 60884-1 standard was written? Does it pre-date usage like this? (talk) 23:33, 20 January 2015 (UTC)
The type letters used in the article are, as it clearly states, those defined by the IEC, but you are quite right that this is informal and does not constitute a standard, variations of the letter system exist and mentioned in the article. The original IEC 60884-1 standard was published in 1987. As an example of planned compliance, the 1984 revision of BS 1363 was aligned, where possible, with the (then) proposed new IEC standard. FF-UK (talk) 00:38, 22 January 2015 (UTC)

────────────────────────────────────────────────────────────────────────────────────────────────────Why then does it come as a surprise that there exist 250 V rated flat bladed ("Type A" and "Type B") plugs "in contravention of IEC 60884-1" when that standard was only published as recently as 1987? The relevant countries (China, Philippines, Thailand, etc.) were using them before that date. (talk) 14:27, 3 February 2015 (UTC)

The usage and existence of such plugs rated at 250V does not come as a surprise. However, it is disturbing that both the Chinese and Philippine standards, current versions of which postdate IEC 60884-1, falsely claim compliance with it. The Philippine National Standard PNS 1572:1997 also states "This International Electrotechnical Commission Standard IEC 83:1975 has been adopted as Philippine National Standard by the Bureau of Product Standards through the recommendation of its Technical Committee on Wiring Devices (BPS/TC 10).
The Technical Committee approved the requirements of this standard particularly the dimensional requirements in Group A. However, a new configuration has been prepared to replace pages 22 and 23 of Group A to suit Philippine condition." As IEC 83 (now IEC 60083) is not a standard, but a technical report which includes descriptions of standards in use around the world, it seems a very inappropriate basis for a national standard!
The discrepancy remains a potentially dangerous situation for the unwary traveller. FF-UK (talk) 15:28, 3 February 2015 (UTC)

Yes one should use plugs of appropriate rated voltage. Even so, it would be pretty difficult to design a plug that was safe at 120V and unsafe at 230V. (That is, that could hold off 120V but breakdown at 230V.) But the problem with using plugs or wiring that designed for less than 230V should be true for any 230V (more or less) country. It seems useless to note it on some. On the other hand, wire that is too small will easily overheat with too much current. This is more of a problem in 120V countries, as the required currents for many loads are higher. I vote for removing the notes, possibly adding a footnote. Gah4 (talk) 04:45, 3 June 2015 (UTC)

Speculation about whether plugs rated at 125V are really quite safe at higher voltages is not appropriate to this page. However, you may want to consider whether the authorities in those few countries which have decided to uprate the American type plug have a greater technical competence than the IEC, which quite clearly rates it at 125V (IEC 60906-2). Also, consider that in IEC 60884-1 (clause 9.2), it states clearly that: "It shall not be possible, within a given system, to engage a plug with a socket-outlet having a higher voltage rating or a lower current rating". The laxity of a few, arguably incompetent, bodies is itself a cause for concern, but not one which can be addressed here! FF-UK (talk) 09:03, 3 June 2015 (UTC)
If speculation about plug ratings and safety aren't appropriate, can we remove all the notes about 120V plugs? Seems to me that they are speculation. Also, the NEMA 6-15 has the same inner spacing as the type A plug, is normally used on 208V or 240V circuits, and seems to be rated at 250V. The note about "within a given system" seems not to apply between systems, though it is fairly easy to take small devices to other countries. Gah4 (talk) 20:34, 3 June 2015 (UTC)
There is nothing speculative about stating that (in relation to a mains supply of 230V): Power cords with type A plugs which are rated at only 125 V may present a safety hazard. IEC 60884-1 clause 9.2 is not a "note", it is a requirement! And, all type A and B plugs and sockets are part of the same system of plugs and sockets. FF-UK (talk) 21:03, 3 June 2015 (UTC)
So, it isn't speculating to say that they may present a safety hazard, but it is speculating to say that they might not? Maybe you should say which safety hazard you are sure will occur? I would trust a US made and sold 125V rated plug over a 250V Chinese market plug just about every day. No more comment about pin spacing? Gah4 (talk) 23:10, 3 June 2015 (UTC)
Sorry Gah4, I really do not see where you are coming from here. A plug cannot be considered safe when operated outside of its rating. That is NOT speculation. Suggesting that operation above the rated values MIGHT be safe is very clearly speculation, and has no place on WP.
I have withdrawn my comment about pin spacing as it is unimportant to the central issue. FF-UK (talk) 06:52, 4 June 2015 (UTC)
OK, but why is a plug only unsafe in certain countries? Isn't it just as unsafe in any country with more than rated voltage? Gah4 (talk) 17:18, 4 June 2015 (UTC)
Yes it is, but if the plug is physically compatible with the socket there is a greater probability that the user will overlook the fact that the voltage in some countries is in excess of the rating of an American plug/cord (and appliance come to that). FF-UK (talk) 19:56, 4 June 2015 (UTC)
Excess rating for an appliance is an important problem, but plug rating doesn't have much to do with that. From a legal point of view, you want to use an appropriately rated plug. (You could be sued for something unrelated to the plug failure.) The article notes that 120V rated plugs are tested to 250V. (I suppose 230V plugs are tested even higher.) Cords with old, worn, or cracked insulation are a very significant safety hazard, but not one that needs to be specified here. The packaging for adapter plugs commonly indicates that they don't change voltage, though people might not bring it along or just might forget it. (More and more devices have universal power supplies, so this is less a problem than it used to be.) Excess current and overheating wires are a significant hazard, not mentioned as much as it could be. Seems to me that a footnote would be enough for plug rating. Gah4 (talk) 23:06, 30 September 2015 (UTC)

Maximum Current/Power Rating[edit]

Maximum Current Power rating to be included in the Table. Presently only Voltage & Frequency is given. E.g. For India, Maximum Current Rating is 5A (Power = Volt*Amp = 230*5 = 1150 VA). Please correct the value if wrong. — Preceding unsigned comment added by (talk) 06:38, 22 March 2015 (UTC)

The primary source for this article does not mention current ratings, which is probably the reason why such information is not included here. It is not clear where such information would be obtained from or to what it would apply. For example, India is listed as using type C, D and M plugs. Type C is the Europlug which is unequivocally rated at 2.5 A, Type D is generally rated at 5 A but the Indian version at 6 A (IS 1293), and Type M is generally rated at 15 A but the Indian version at 16 A (IS 1293). FF-UK (talk) 11:58, 22 March 2015 (UTC)
The UK type G plug is referred to as a 13 A plug. However the maximum current rating of the infrastructure depends on other factors, a significant number of 13A plugs (which can be, and usually are, fused lower) would probably connect to a 2.5mm copper cable ring main, while cookers (domestic ovens) are fed by 6mm copper cable mains, which are basically rated at 32A. Conversely a domestic lighting ring main would generally run on 1.5mm copper cable. All the best: Rich Farmbrough23:53, 2 June 2015 (UTC).

Three phase[edit]

I added a note about three phase, nominally phase-to-phase 230V systems are at 400v, 220v systems are at 380v, and I believe 240V systems are rated 420V, though I have seen 415V and 440V. Someone with more knowledge (and better references) might like to improve what I wrote, and add the distinction between phase-neutral and phase-phase. Or maybe we should have a separate article on industrial electricity supply. All the best: Rich Farmbrough23:30, 2 June 2015 (UTC).

The factor is the square root of three, so you can check any of those. The common ones in the US are 120/208 and 277/480, the latter often used for lighting in commercial applications. Other possibilities are 230/400, 220/380, and 240/415, rounded conveniently. Gah4 (talk) 04:51, 3 June 2015 (UTC)
Both this article and its primary source are concerned with single phase domestic supplies, that is made clear in the voltages section. I have therefore removed the redundant additional note. FF-UK (talk) 08:44, 3 June 2015 (UTC)