timmeh2 Posted November 3, 2009 Share Posted November 3, 2009 Playing devil's advocate for a minute it doesn't really matter which way you wire L and N, as they are shorted together anywayReally? so why don't things go BANG every time we plug them in? there maybe a low resistance between live and neural,but unless somethings gone wrong it most definatley aint a short.Its important that live goes to live or you could find you've got protective devices and switches in the neutral,not very nice when it comes to fault finding a circuit that is supposedly switched off,and even more unpleasant if the wiring is one of those rare,but still out there tn-c (concentric earthing I think its called in old money) system Hi If you re-read my above post I was talking about generic incandescent lighting, which most definately are a short, else they wouldn't work. As I'm sure you know that for some lamp holders (including discharge) both wires are coloured white so once you've poked them through the chassis you can't tell which one is which. All the best Timmeh Link to comment Share on other sites More sharing options...
boatman Posted November 3, 2009 Share Posted November 3, 2009 Playing devil's advocate for a minute it doesn't really matter which way you wire L and N, as they are shorted together anywayReally? so why don't things go BANG every time we plug them in? there maybe a low resistance between live and neural,but unless somethings gone wrong it most definatley aint a short.Its important that live goes to live or you could find you've got protective devices and switches in the neutral,not very nice when it comes to fault finding a circuit that is supposedly switched off,and even more unpleasant if the wiring is one of those rare,but still out there tn-c (concentric earthing I think its called in old money) system Hi If you re-read my above post I was talking about generic incandescent lighting, which most definately are a short, else they wouldn't work. As I'm sure you know that for some lamp holders (including discharge) both wires are coloured white so once you've poked them through the chassis you can't tell which one is which. All the best Timmeh This is just getting silly. In any generic fitting the live and neutral are NOT SHORTED TOGETHER. If they were, the circuit protection on the dimmer would trip every time you connected a fitting to that channel. The plug will be shorted to the lampholder via the appropriate conductor, but they are not shorted together. Link to comment Share on other sites More sharing options...
themadhippy Posted November 3, 2009 Share Posted November 3, 2009 for some lamp holders (including discharge) both wires are coloured white so once you've poked them through the chassis you can't tell which one is whichhope you aint wiring ES lamp holders any way round. Link to comment Share on other sites More sharing options...
timmeh2 Posted November 3, 2009 Share Posted November 3, 2009 This is just getting silly. In any generic fitting the live and neutral are NOT SHORTED TOGETHER. If they were, the circuit protection on the dimmer would trip every time you connected a fitting to that channel. The plug will be shorted to the lampholder via the appropriate conductor, but they are not shorted together. Hi I agree entirely, it was not my intention to create an argument on something as trivial as which way L and N goes on a Parcan. The point I was trying to make is that on a generic, L and N are connected together by the lamp's filament. It doesn't matter which way the current flows though it, the end result is the same. It might be an inductive load, but it is a short nonetheless. All the bestTimmeh A concurrent post has been automatically merged from this point on. for some lamp holders (including discharge) both wires are coloured white so once you've poked them through the chassis you can't tell which one is whichhope you aint wiring ES lamp holders any way round. Absolutely not. ES terminals are marked and are therefore fitted accordingly. Link to comment Share on other sites More sharing options...
JimWebber Posted November 3, 2009 Share Posted November 3, 2009 I know what you are trying to say Timmeh, but although it may be a low resistance, it is not a "short". There is a subtle difference....... I see where you are coming from, but some less experienced knowledgeable people (And after all, isn't this the whole point of this forum to offer advice to the less experienced?) would not be able to make this distinction. Now I am going to play total Devil's Advocate here Henry, look at the argument that your simple question has provoked as to the best way to wire your plug!!!!!!!! Who do you listen to?Who is right?Are we all right?Are we all wrong?What bits of our advice are you going to listen to? Hence my original comment, find a competent person, who can teach you how to do it. Relying on instructions from a bunch of complete strangers MAY (and I emphasise the may) not be the best idea! Above all, learn and be safe! Jim Link to comment Share on other sites More sharing options...
David Lee Posted November 3, 2009 Share Posted November 3, 2009 Hi As an aside you definately SHOULD NOT be using these types of plugs, as they are neither CE or Kite Mark stamped. Any PAT Tester worth his salt would fail any equipment with these plugs attached, I certainly would (and do.) http://i622.photobucket.com/albums/tt309/themainsman/iec-plug-blk.jpg Those are trailing sockets ;) Link to comment Share on other sites More sharing options...
musht Posted November 3, 2009 Share Posted November 3, 2009 Think its the lack of any moulded in approval stamps that makes them bad, possibly very bad, think of a live trailing socket coming to bits in your hand. Guess the same maker probably makes just as `good` a plug. For the OP get some Bulgin branded IEC plugs to start with, the cheapies can reduce even the most experienced plug wirer to a jumping up and down on crap connectors rage.... Link to comment Share on other sites More sharing options...
henryb_y_o_b Posted November 3, 2009 Author Share Posted November 3, 2009 thanks for all the advice! Henry Link to comment Share on other sites More sharing options...
grizzly Posted November 3, 2009 Share Posted November 3, 2009 Think its the lack of any moulded in approval stamps that makes them bad, possibly very bad, think of a live trailing socket coming to bits in your hand. Guess the same maker probably makes just as `good` a plug. I expect that the connectors have plenty of approval stamps on them, just not the Kite Mark (or apparently CE mark, for what it's worth).Any 'PAT tester' worth 'his' salt would understand that IEC 60320 is an international standard, so not every brand of IEC connector will have been Kite Mark approved, but may have such approval marks as 'UL Listed', 'UL Recognised' (both USA) or 'GS' (Germany), amongst others. ;) Link to comment Share on other sites More sharing options...
paulears Posted November 3, 2009 Share Posted November 3, 2009 I do wish we'd stop calling the resistance of a lamp a 'short circuit'. It's patently not a short circuit, and it's just the wrong term to use - especially in a topic that is dealing with beginner/basic level content - it just promotes the idea that this is what it is. The other thing that's got out of hand is the idea that you should not attempt to fit a plug, unless you can do it - a circular argument. As some have said, there's no problem at all with fitting plugs. I used to do this with my students - not just the technical one - everybody did it. The process of fitting plugs requires some dexterity that may have to be developed. It really isn't that easy to estimate how much of the outer to remove, and then do it without slicing into the conductor insulation. Cutting the 3 cores to fit the connector also takes care and skill - especially so in IECs where space is very limited. The end needs very careful preparation to get the 3 conductors the right length, and the middle one needs to be slightly shorter. Everyone should practice doing these things - if you can do an IEC, most of our other connectors are a doddle! The critical thing is to get your first ones checked by somebody before you start to use them. Now for the bit many people won't like. If the item has been properly tested, then chopping one plug off and sticking another on would, for me, simply mean a visual inspection of what I've done. I would not retest again, just because I changed a plug. I'm sure many will disagree, and maybe if a tester just happened to be sitting there, I would - but if one wasn't available, I'd have no issues at all. I trust my plug putting on skills. For a newbie, there are quite a few ways you could mess up, hence the need for another set of eyes. Link to comment Share on other sites More sharing options...
timmeh2 Posted November 3, 2009 Share Posted November 3, 2009 Hi The one I'm currently holding in my hand (exactly like the photograph I provided) has no stampings apart from the manufacturers name and product code. I think it's fair to say that anyone who's come across them would consider them a risk and choose not to use them. Also for insurance purposes - if a fire happened and the connector was at fault - questions might be raised over its use as it doesn't have a kitemark. A third and final point is these connectors are not rated to 13A - this one is only rated to 5A. Again, this is another source of risk because it is not rated past the current it might be subjected to. All the bestTimmeh Link to comment Share on other sites More sharing options...
grizzly Posted November 3, 2009 Share Posted November 3, 2009 The one I'm currently holding in my hand (exactly like the photograph I provided) has no stampings apart from the manufacturers name and product code. A third and final point is these connectors are not rated to 13A - this one is only rated to 5A. How do you know it's rated at 5A if all there is stamped on it is manufacturer & product code? ;) Although, to be fair, there does seem to be some confusion here: the website of the cable supplier states that they are rated at 15A, but IEC C13 & C14's shouldn't be anymore than 10A. Link to comment Share on other sites More sharing options...
LXbydesign Posted November 3, 2009 Share Posted November 3, 2009 Yeah right , so my comment at the very beginning pretty much sums it up Henry.!! If you've never wired up a IEC before, regardless of your experience, get a competent person to show you how to!! Theres no shame!! That way you know you are doing the job properly and safely!! Wiring up an IEC isnt hard, its just a bit more fiddly than a standerd 13apm plug. And as was mentioned , once you've been shown how to do it correctly, then have a go yourself on a bit of spare cable and then your ready to rock and roll! Link to comment Share on other sites More sharing options...
oilyspark Posted November 3, 2009 Share Posted November 3, 2009 HenryWhile I'd agree with the general principle that you should have someone physically check your work, and not rely solely on 'internet advice', there are indeed a couple of specific points to consider. 1. Choose your plug carefully. Types with pillar terminals (i.e. the cable is inserted through a hole and clamped by the end of a screw) are usually much easier to make a good job of, than the type where the cable wraps around the screw.2. If you must use a wrap-around type, take great care with preparing the wire ends into eyelets, so that the strands do not splay as the screw is tightened, as this will invariably cause the screw to slacken over time.3. Do not tin the ends (with solder)! I have seen so-called professionals advise this because of the strand-splaying problem. Tinning often causes bad connections because the solder-laden wire is pliable and creeps out from under the terminal.4. With some types of plug, the earth core must be left longer than the live and neutral, in order to pass around the cover screw, quite apart from the extra slack you should give it.5. Beware the tendency for the cable clamp screws to bite into the live and neutral insulation. Get the sheath as far inside the plug body as practical.6. Yes, the terminals will always be marked for polarity. You will find the layout extremely familiar when you compare it with other common plugs. @ anybody who misuses the word 'short' - it means specifically a fault that diverts current from its intended path. By definition, even a solid copper bar is not a short, unless it's across your busbars :) Lucien Link to comment Share on other sites More sharing options...
tony g Posted November 3, 2009 Share Posted November 3, 2009 - Appropriate lengths in wires, particularly for what happens if scenarios. In a plug, if someone tugged the cable hard, I'd like to see the live wire disconnect first, and the earth last, so consider how much slack you leave. Hi Most electricians I know would consider that wrong - you want to have both the L and N the same length so both are disconnected at the same time rather than leaving half the circuit intact. All the bestTimmeh Just to settle this one, You will find it near on impossible to wire a 13A plug with live and neutral the same length without kinking the live, I have a demo model of the MK toughplug, Duraplug, Crabtree, BG & WG plugs in my teaching kit box (I teach electrics when I'm not doing it) and you can't wire any of these properly with same length L&N, in any case the live will, generally always pull out before the neutral because the live goes straight up to its terminal whereas the neutral goes round a portion of insulation and down into it's terminal so it is mechanically more difficult to pull out. I've dug out a dusty copy of BS1363 (plugs, 13A) and that was the original rationale behind the design, that live will pull first. I would disagree that you shouldn't wire a particular type of plug or fitting because you havn't done it before, after all I'm continuously being asked to wire new designs of product I've never seen before - what counts is having the right amount of knowledge, experience and skill to do the job, and if you are still not sure the sense to ask another professional for their advice. Link to comment Share on other sites More sharing options...
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