Harmonised and non-harmonised cable in same circuit?

[Spook]

This is such an obvious question it must have been asked in some form already. If it has, sorry for the repetition.

I need to replace a length of cable on my upstairs lighting circuit which was damaged when I had a bit of work done to the roof, and while I’m at it I’m going to move a switch and replace the cable servicing that as well.

What’s just struck me is that the cable I’ve got is harmonised, having the new core cabling colours, while the rest of the circuit isn’t. Is it okay to mix harmonised cable with the existing stuff? And, just out of interest, what’s going to happen come next year if, say, someone wants a ring circuit extended - will their electrician have to replace the entire circuit with new cable?

I’m sure I’ve read somewhere that you will be able to have both types of cable as long as this is clearly indicated somewhere on your consumer unit - have I imagined that or is it the case?

Cheers.

Spook.

 

[1974stephen]

It's OK to mix harmonized and non harmonized, but you must install a label on the consumer unit clearly stating that two colour codes are in operation on the installation. These are available from all electrical trade counters. There are specific ones that meet 5839 as a bit of paper stuck on saying it doesn't quite do I'm afraid!

 

[toasty]

You can still get old skool cable, if you look hard enough, in your case it might be easier to get hold of some of this.

I recently bought a load from B&Q at a greatly reduced price because of the old wiring colours, it doesn't bother me in the slightest, wire is wire at the end of the day, I much prefer the old colours anyway, much easier to distinguish in the dark.

Good luck

 

[ban-all-sheds]

If you'd rather turn a quick profit than hoard it for nefarious purposes, I've recently seen people pay nearly £50 (inc delivery) for 100m of red/black 2.5mm² on eBay...

 

[Nijinski001]

I thought it was now against regs to use red/black?

Are the e bay'ers hoarding it for Antiques Roadshow in 2085.

 

[ban-all-sheds]

No - you may use it until April next year for extending/altering existing installations.

Thereafter it will contravene BS 7671 to use it. However - if you were doing a PIR, and you found that an existing installation had been extended after March 06 with old colours, what code would you give it?

Interestingly, if you look at the Building Regs, which don't mandate 7671, but do require that "Reasonable provision shall be made in the design, installation, inspection and testing of electrical installations in order to protect persons from fire or injury", I think you'd have a good case for continuing to use the old colours for extending/altering, particularly for 3C+E.

 

[Qedelec]

How would you know when it was extended?
Personally I can't see any good reason to try and fool anyone. Safety should be paramount.

 

[ban-all-sheds]

How would you know when it was extended?

It was a hypothetical situation. Never mind how you could tell, let's say that you could tell. What code would you give it?

Personally I can't see any good reason to try and fool anyone.

I never said anything about fooling anyone.

Safety should be paramount.

Indeed - hence my point about it being arguable that continuing to use old colours is safer than mixing them.

 

[Adam_151]

How would you know when it was extended?

It was a hypothetical situation. Never mind how you could tell, let's say that you could tell. What code would you give it?

Couldn't justify anothing other than a 4 IMHO, I suppose there could be a situation where you think there is a real risk that someone working on it in future could confuse conductors, but thats probably a separate issue, because it such an issue could also have been created during the changeover period, and so its a fault in terms of lack of appropiate marking, rather than an issue of using old colours in summer 2006...

 

[pdcelec]

We have recently discussed this at work regarding colours. Here is a possible scenario (lets just consider the neutral):
---------------------------------------------------------------

Existing mains (three phase) RED-YELLOW-BLUE-BLACK

New mains tails BROWN-BLACK-GREY-BLUE

Existing ring in property RED-BLACK

Alteration to ring in property BROWN-BLUE
---------------------------------------------------------

So the neutral of the ring in the property is wired (from mains)

BLACK-BLUE-BLACK-BLUE

The phase conductor (on blue phase)

BLUE-GREY-RED-BROWN
------------------------------------------

Confused with this safety requirement!

I can see in the very near future, people such as small factories connecting up blacks to blacks and blues to blues and BANG.

Colour blind people will be at a great advantage since they will just continue with testing each conductor as they did before.

 

[plugwash]

I can see in the very near future, people such as small factories connecting up blacks to blacks and blues to blues and BANG.

yeah its more likely to be equipment destroyed than anyone hurt by this though imo.