Using Green/Yellow not as CPC

[sparkinlee]

Here's quick question...

Can I sleeve a green & yellow flex conductor with brown or blue to use it as a switched live or neutral?

I'm looking at a situation where I do not need the CPC connection (the timer switch I'm connecting to is class 2 insulated) but I do need live, neutral and switched live. So I'm wondering if I can use 3 core flex (so that the conductors are all insulated within the outer sheath, unlike T&E) and put a brown sleeve on the G/Y to use it as the switched live.

Thanks for your help, and sorry if this has been answered many times before!

 

[nickblake]

Yes the green and yellow should only be used as a earth conductor but if you sleeve it with another colour ie brown/blue not a problem this can not be done with twin and earth cable. regs state green and yellow should only be used for
earth conductor this is correct but you have sleeved it its now not a earth conductor.
its no different than sleeving say a blue switch wire with brown sleeve or the black of a 3 core armoured yellow and green sleeve/tape.but after saying all that the flex you are using in that situation should still carry a earth.

doesnt matter mate not permitted in regs ,cpc's on cable TWE or #flex should never be used as a live conductor simples read back on some of the posts

 

[nickblake]

For this type of work you should use a 3 core cable. In T&E the cross section of the earth isn't the same as the lives; so earth shouldn't be used as permanent live. Just my opinion.

use a 4 core so that any future modifications that may require an earth are then provided , i always make a earth available for that exact reason not connected but there

 

[SPARTYKUS]

...and what if someone taps into the cable in the future and sees the section thats not sleeved, but still green and yellow? Might get a shock!

 

[sparkinlee]

Thanks all for your comments on my original post - as a one person operation this is a very useful resource to get others' opinions.

With reference to some of the comments, I knew there were more issues with T&E because of the smaller conductor size of the CPC and that it is uninsulated inside the outer sheath.

Neither of those applies to flex though which is why it occurred to me that it might be possible to 're-label' the green/yellow, but you've pointed me to the regs which say no, so that's that!

Thanks again.

 

[Deleted member 26818]

The restriction against using G/Y as anything other than a CPC/earth, only applies to single core cables, here is an excerpt from 514.4.2: "Single core cables that are coloured green-and yellow throughout their length shall only be used as a protective conductor and shall not be over-marked at their terminations, except as permitted by Regulation 514.4.3."
Whith multicore cables such as flex, or SWA, it is allowed to oversleeve the exposed core another colour.

 

[nickblake]

reading that reg i would asume it applies to a neutral connection not a live , i know they are both classed as lives , but my interpritaion is blue can be used as a cpc or a cpc can be used as a neutral no other colours mentions so im assuming they are refering to the #pen and neutral connection i stand to be corrected if im wrong its getting late and my brain needs to reboot

 

[pennywise]

The regs only mention the "colour" combination code of green and yellow must only be used exclusively for the cpc to identify it, not the conductor itself which could be re sleeved to any colour. This could be why the NIC say it's ok, don't shoot the messenger

 

[robsparky1975]

I have seen people use t&e and sleeve the CPC with red for a 2 way,yuk,ripped out and replaced,also if any unused cores in a multicore cable are not used its good practise to pair with the cpc.

 

[Des 56]

Having never done so, I did think the ref to single core cables coloured G/y blah blah then meant multi core flexible cable G/Y could be oversleeved as live, but nickblakes interpretation seems sensible

I wonder if guidance note 1 has this in its covers ?

It is a deviation to apply colours to flexible cores to identify them as being used for a purpose other than that which their original colour indicates - if, after due consideration, colours are applied the deviation must be clearly recorded on the Electrical Installation Certificate

 

[Doomed]

I concur with Pennywise, its OK to oversleeve multicore flex's CPC.
But it is an abomination and smacks of being unprofessional.

Although I had to do this once for a short length of flex (50cm) connecting a dusk / dawn sensor to the fixed wiring. Still regret doing it.

 

[SirKit Breaker]

You always are Howard, I'm just the saddo looking it up but at least the op knows why it can't be done for future ref.

Not always Paul, but when i get it wrong i dont do it by halfs, and boy can i ferkup sometimes..................I managed to make a proper balls of my own bathroom fan last week, but dont ask

Cheers..........Howard

 

[coomers]

doesnt matter mate not permitted in regs ,cpc's on cable TWE or #flex should never be used as a live conductor simples read back on some of the posts

a cpc must be connected to earth to make it a cpc otherwise its called a conductor, sleeve conductor and it can be used for any purpose. Had deep discussions with city and guilds lecturer about this many years ago and also niceic inspector and what he didnt know about regs wasnt worth knowing simples !

 

[robsparky1975]

Not always Paul, but when i get it wrong i dont do it by halfs, and boy can i ferkup sometimes..................I managed to make a proper balls of my own bathroom fan last week, but dont ask

Cheers..........Howard

oh go on please share lol

 

[robsparky1975]

To me all multicore cables be they t&e,3,4 or 5 core flex etc should incorporate a cpc,i dont have the brb to hand but think there might be reference to something like this,no matter how short the run is.

 

[Paul.M]

A cpc is required the full length of the cable. If the op uses the cpc for a switch wire, no more cpc.

Using the cpc in multicore as a current carrying conductor is not allowed as it needs to have insulation.

As for changing the use of a cpc (with insulation + correct csa for its purpose + having a cpc for the full cable run) and change it to a live/line conductor and sleeve it at each termination and note it on the cert........ forget it, I'm off to the wholesalers to get the correct cable for the job.