EU/UK mains wiring colours and other stuff  - Page 1
Forum section: electronics / general

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 10:42:40 am
content: Well first of all I want to know why the UK changed the color of mains wiring to blue and brown from black and red. My brain is STILL hard wired to think Red and Black. Likewise why is it that all the equipment I buy or DC stuff is still in Red and Black wires on the power side of things, even the DMM input leads are thus. Why did they not change everything to brown and blue !. Most annoying.Next, I notice that these PSU's that are on sale have a green output on them yet can I find a black/green/red triple lead to connect to anything, no. Only the usual red and black with croc clips and banana plugs on. Do manufacturers not think people use all three outputs and will thus want leads to fit.I am sure I will find other things to moan about later.

author: rolycat
author_rank: Super Contributor
timestamp: May 29, 2015, 11:16:20 am
content: Quote from: Deathwish on May 29, 2015, 10:42:40 amBecause red and black denote DC positive and negative, whereas brown and blue denote AC live and neutral.UK flexible mains wiring has used brown and blue since the 1960s - how long has this been bugging you?QuoteIt's unusual to require a separate earth/ground connection to a circuit - it's more common to short the green earth connection to either black or red at the PSU if you require a positive or negative grounded supply. A third wire would be as useful as a third leg - sometimes handy (or leggy?), but usually it would just get in the way.QuoteWell, you could moan about the fact that there are no standard colours for DC supplies with both positive and negative outputs and a common terminal.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 11:29:49 am
content: Quote from: rolycat on May 29, 2015, 11:16:20 amSince the early 70's when i got a shock as a kid .....QuoteI still want one just to be awkward.Quoteconsider it in the pipeline. I want the world my way, or there will be big trouble in little UK. I aim to take over the world.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 11:33:25 am
content: Incidentally, I demand that all DMM's used on mains supplies come with a set of probes in Brown and Blue just to be a tard and that they all come with a 10A fuse in the end of the lead for those who buy DMM's without fuses on board.

author: sync
author_rank: Frequent Contributor
timestamp: May 29, 2015, 11:37:40 am
content: Quote from: Deathwish on May 29, 2015, 11:33:25 amAlso all DMMs used on mains should have 3 phase inputs.

author: madires
author_rank: Super Contributor
timestamp: May 29, 2015, 11:56:31 am
content: Quote from: sync on May 29, 2015, 11:37:40 amAnd a CEE socket to connect the test leads

author: Howardlong
author_rank: Super Contributor
timestamp: May 29, 2015, 11:57:03 am
content: The story I heard decades ago was that it was a colour blindness thing, blue and brown are apparently more easily distinguishable for the general populous.As a kid in the early 70s I did find it difficult to remember, those were the days when we wired our own plugs. I doubt most kids would have a clue how to wire a plug nowadays with pre-moulded plugs being the norm, in fact I think it may even be illegal to sell a mains powered unit these days in the EU without a pre-fitted plug.

author: tautech
author_rank: Super Contributor
timestamp: May 29, 2015, 11:58:25 am
content: Quote from: Deathwish on May 29, 2015, 10:42:40 amYou sure will, USA AC mains are black and white.Get you head around that..... but of course its just what you are used to.We in NZ were red and black for mains years ago, now brown and blue, however TPS cabling that sparkies install is still red, black and green, go figure that.Maybe they don't want to confuse the sparkies.

author: rolycat
author_rank: Super Contributor
timestamp: May 29, 2015, 12:06:33 pm
content: Quote from: tautech on May 29, 2015, 11:58:25 amAnd black is liveOf course, all that nonsense will go away once Deathwish achieves world domination.

author: Delta
author_rank: Super Contributor
timestamp: May 29, 2015, 12:10:19 pm
content: It was to "harmonise" us with the EU. They also made us go from nice, bright, primary colours (red yellow and blue, with black for neutral) for three phase, to brown gray and black(!) with blue for neutral. RYB were easily identifiable in a dark owered down panel, brown gray and black, not so.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 12:12:12 pm
content: Hi Tautech. hope its a nice day where you are.Black and white are closer to Red and Black so I could probably deal with that.I know it is illegal to install anything mains without a PAT test here in the UK now, I went ahead and installed a power shower. They had re-wired the house some weeks before and i was adamant that it was going in regardless at no further cost to me just for a test, it wasn't rocket science to add a new fuse to the consumer board etc. When they came round later to check it all and sign it off they questioned it but I gave them some blarney about it being an old installation, I got a dodgy look but no more said.

author: Mechanical Menace
author_rank: Super Contributor
timestamp: May 29, 2015, 12:12:13 pm
content: Quote from: Howardlong on May 29, 2015, 11:57:03 amThat's what I was taught.QuoteWe were still taught how to wire a plug etc when I was at school, and it was recapped more than once. I could ask my little brother if they still are.

author: tautech
author_rank: Super Contributor
timestamp: May 29, 2015, 12:17:08 pm
content: Quote from: Deathwish on May 29, 2015, 12:12:12 pmBrilliant, light frost to start and a beauty fine day, topped off with the knowledge you are still sucking air.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 12:19:31 pm
content: Quote from: tautech on May 29, 2015, 12:17:08 pmI suck at doing anything electronic. Math is not a strong point so I will never design anything or take a degree in it. But I try, in fact I have been told by a number of women i am very trying including my two daughters living in Oz. Go figure

author: tautech
author_rank: Super Contributor
timestamp: May 29, 2015, 12:26:27 pm
content: Quote from: Deathwish on May 29, 2015, 12:19:31 pmDon't worry, very few understand.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 12:29:08 pm
content: I'm not, i will only die once or twice then it is final and I refuse to come back because lets face it, if you keep failing whats the point, I must be the only guy who needed a TomTom sat nav to get around a service sheet.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 12:31:23 pm
content: In fact I am still wondering why it hurts when i lick the end of the soldering iron to clean it . I will win though

author: tautech
author_rank: Super Contributor
timestamp: May 29, 2015, 12:35:14 pm
content: Quote from: Deathwish on May 29, 2015, 12:31:23 pmOnly the Welsh.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 12:40:30 pm
content: I am an Englishman in a foreign land,why am i here , i have no idea, I just figured I would look more intelligent. Seems i was wrong.

author: madires
author_rank: Super Contributor
timestamp: May 29, 2015, 12:51:47 pm
content: Quote from: Delta on May 29, 2015, 12:10:19 pmOver here 3-phase is black, brown and black, and since 2006 brown, black and grey for L1-3. Single phase is black or brown (L, brown since 2006), blue (N) and green-yellow (PE). Very old wirings got black (L), blue (N) and red (PE) or black (L), grey (N) and red (PE). Cables with 4 wires for switched stuff, like lights, got black (L), bown or grey (switched, grey since 2006), blue (N) and green-yellow (PE). Brown was also used before 2006 for L in standed wires.

author: Zero999
author_rank: Super Contributor
timestamp: May 29, 2015, 10:12:58 pm
content: Quote from: rolycat on May 29, 2015, 11:16:20 amNo, the regulations also specify brown and blue to be used for DC as well as AC in buildings.Blue is always the earthed conductor, whether it be AC neutral or the side of the DC power supply connected to earth (which could be either positive or negative).Grey is the negative conductor, if it's the unearthed side of the supply.Brown is the positive conductor if it's the unearthed side of the supply.http://electrical.theiet.org/wiring-regulations/cable-colours/harmonised.cfm?type=pdfQuote from: Delta on May 29, 2015, 12:10:19 pmI've never understood the purpose of harmonisation with the EU for fixed wiring. It's fair enough if the wiring is in a product which is being exported to the EU but it's none of their business what colour the wires are inside fixed installations.Perhaps it was done to keep the European cable manufacturers happy so they can sell to the UK?Quote from: Deathwish on May 29, 2015, 12:12:12 pmNo, it's nothing to do with PAT which is portable appliance testing and doesn't cover fixed wiring such as a shower. Fixed installations need to comply with part P.http://en.wikipedia.org/wiki/Electrical_wiring_in_the_United_Kingdom#Legal_and_regulatoryIn reality there's no real way of policing this, as long as you don't do anything dangerous then you'll be fine.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 10:38:32 pm
content: I like you Hero, your my kind of person, I only remember the brown / Blue wire thing because I have it in my head that the first two letters of BLue = BLack so I guess my having 2 brain cells works, both are filled at the same time digital 0 or 1 and no one make a wise crack about that being digitally 16 bits please. I know it is notWoohooo.

author: rolycat
author_rank: Super Contributor
timestamp: May 29, 2015, 10:58:17 pm
content: Quote from: Hero999 on May 29, 2015, 10:12:58 pmI learn something new every day on this forum. However, in this case I think the regulations are nuts.

author: Deathwish
author_rank: Unknown
timestamp: May 29, 2015, 11:17:25 pm
content: Hi Rolycat, yeah me too, problem is I have a bad memory and a learning disability but hide that part well, I did electronics over 20 years ago, learnt a lot, did TV and Vid repairs and then gave up for other things (wife and kids), I never give out advice as there are those far more able than I and even if I know the answer I wont speak up, on here that seems to be a danger because to me there are those who have professor level ability and question it. also being told as a kid you will never be anything and told to shut up and be seen not heard had its impact. I like to try and ask sensible questions that puzzle me but add some humor too it or it ends up a drudge and i then tend to walk away from it. Lots of nice people in here though so its all good.