Cable colours grrrrr

[David Hansen]

On Wed, 7 Feb 2007 18:46:21 -0000 someone who may be "The Medway Handyman" wrote this:-

Because in the old colours black was the neutral, now it is a phase. In the old colours blue was a phase, now it is neutral (though the colour of the two blues tends to be different).

The IEE got this right in my view. In single phase wiring what is required is a warning notice at the origin of the installation. People were already familiar with red to brown and black to blue transitions, because they have occurred for decades going from fixed wiring to cords.

In three phase wiring I think they were right to specify labelling at each junction between the two colour schemes. Such wiring is usually seen outwith houses, often with single cables in conduits where it would be easier to make a mistake. Although a mistake should be spotted in testing it is better not to make it.

[Huge]

I'll buy it.

[Cuprager]

was there a reason for the change? it seems to me like they have created a hazardous situation!

[John]

what other reason but EU harmonization?

John

[Dave Liquorice]

Harmonisation.

[Dave Plowman (News)]

It should have been changed many years ago along with flex.

[Ben Blaukopf]

Amazed at how many responses there have been to this - nothing like a moan about the regs to get everyone worked up.

Black was a phase colour too though, as switched live on light switches. I gather some installations have the earth wire as a live on two-way lighting where the installer ran out of three core...

I've got some old three core left over which I used for wiring my thermostat. If the BCO moans about the colours then I'll change it, but I doubt he will. I think doing my entire kitchen ring in old colours might annoy him a bit though.

Old colours doesn't matter for non-notifiable work, since the new colours have been around since April 04. I bought my house at the end of '05 so I can't really claim that I did anything pre-P.

Colour change label has been on my system for ages anyway.

Ben

[John]

You're not wrong but then again, neither was I, because I knew that the Z is now accepted by the Oxford dictionary - ergo, no real reason for your correction.

[David Hansen]

On Thu, 08 Feb 2007 16:21:18 +0000 someone who may be Cuprager wrote this:-

The IEE put off changing to the standardised colours for a very long time, because they were concerned about danger. I would have done it long ago, but the delay has the advantage that it has been possible to get three colours for phase conductors that don't clash with other schemes. That wouldn't really have been possible earlier.

Some of the changes to the colours for DC wiring are even more fundamental.

[Dave Plowman (News)]

But the colours *do* clash - black being the old neutral. I realise it was probably impossible to find a decent set of 'colours' that didn't clash somewhere in the EU.

[Dave Liquorice]

What are you wibbling about I didn't correct anybody I gave a single word answer to the question asked.

[John]

My sincere humble apologies to Mr. Liquorice. For some strange reason - and not least because this posting appeared underneath mine - I got it in my head that Dave was directing this post to me in order to correct my use of the Z instead of the S in "harmonization", hence my defence of citing the Oxford Dictionary. I now realize that I was completely mistaken and that Dave was, in fact, replying to Cuprager.

Where the hell I got that idea from I do not know. I blame it on the tablets :o)

John.

[Andy Wade]

Clashes in respect of blue and black were absolutely inevitable. The reason that "the IEE" (actually the BS wiring regs committee JPEL/64) delayed this change was to get the option to use _three_distinct_ phase colours, so preserving the ability to determine the phase rotation direction from the wiring colours. Elsewhere various combinations of brown and black are used, with the consequence that the rotation becomes a matter of trial and error, or needs to be determined with an instrument.