CPC used as live

[drew35]

I carried out the new PIR / condition report today and found a diy bodger had added two way light switching, in flex ,using the cpc as a live, in almost every room!

Now I thought code 2, but I cant find any reference to it in the best practise guide. I know it was once upon a time a done thing to use the cpc as a live in two way light switching, but this has been done recently.

I was sure there was a regulation stating that a cpc can never be used as anything but, even if it was sleeved? I can't find it except for single core reference.

411.3.1.1 A cpc shall be run to, and terminated at each point in wiring, and at each accessory.

514.3.2 Every core of a cable shall be identified at its terminations and preferably throughout its length. Sleeves for identification should comply with...

514.4.2 "SINGLE CORE CABLES" that are coloured green and yellow throughout there length shall only be used as cpc and not over marked at their terminations.

But 411.3.1.1 demands an earth anyway so its still wrong even if it were sleeved? I'm trying to recommend the best fix, without destroying every other wall and rewiring, all I can think of is to convert to one way switching with an earth? Although you can have a lighting circuit without a cpc as long as you comply with all the requirements, so do I put a sticker on the consumer unit saying the lighting circuit has no cpc and then sleeve all the live cpc's brown at each termination?

 

[SirKit Breaker]

It is not acceptable to use a CPC as a live conductor, sleeved or not. The CPC in T&E is only about 2/3rd's of the CSA of the live conductors, so its current carrying capacity is lower.

CODE 1 in my opinion......end of.

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

 

[Deleted member 9648]

Unfortunately it is permitted to use a G/Y which is part of a sheathed cable as an energised conductor....although IMHO it should not be. The OP states flex,not T/E.
As long as the flex meets the requirements for a cable as installed,and the G/Y is identified at each end,IMO you can only code the lack of a CPC at an accessory,not the use of the G/Y conductor.

 

[highspark]

If size of CPC can carry permitted current and is sleeved brown then its not a 1 or 2 but a 3

 

[telectrix]

as wirepuller says, not good practice, but no reg. banning the use of an over sleeved Gn/Y as a "live" conductor, as long as there is a cpc to the accessories, a C3, IMO.

 

[Darkwood]

The cable itself has probably got 3 line conductors and if accidentaly cut wont operate any mcb's and could be a hazard to any trade not realising its been cut or damaged thus having exposed live wires, in my view the cable probably wont be mechanically protected so should have an earth run with it, lets hope its covered by an rcd to minimise the potential hazard....

 

[mogga]

Im with SIR on this one IMO G/Y denotes EARTH and as such no voltage carried I dont care what the regs ,boffins say G/Y or bare conductor should NEVER be used as anything but earth
What about the guy who comes along to add a light later or alteration splits sheathing away and cuts the "earth" BOOM Its not bad practice its not against the regs its downright dangerous

 

[Doomed]

Many a time have I found 3 core flex used to wire a cylinder stat or a photocell, both items being class II so the cpc being used as a conductor. As long as the cpc is sheathed and the flex at no point is hidden I have let this go with out raising the isue or altering it, am I wrong in this?
(Note: never found it as part of an inspection, just when working on a installation)

 

[RogertheBodger]

Many a time have I found 3 core flex used to wire a cylinder stat or a photocell, both items being class II so the cpc being used as a conductor. As long as the cpc is sheathed and the flex at no point is hidden I have let this go with out raising the isue or altering it, am I wrong in this?
(Note: never found it as part of an inspection, just when working on a installation)

Don't think you're wrong, we're not going to run down to the wholesalers for a couple of meters of correctly colored flex when we can use a sheathed cpc. common sense has to prevail sometimes.

Ps. been dying to ask you for ages about your Avatar, looks like a Battle cruiser to me, is it H.M.S. Hood? does she have some significance for you?

 

[Darkwood]

most wholesalers will cut 4core flex to length, assuming youv'e already weighed up the job there is no excuse to inplement this method unless your a DIY or bodgit and scarper, its poor practice at the very least and ust because the regs dont specify this particular case dont mean it ok.

 

[Doomed]

yep, H.M.S. Hood, well spotted.
Its old, mighty, English but unfortunately Doomed........

 

[Doomed]

most wholesalers will cut 4core flex to length, assuming youv'e already weighed up the job there is no excuse to inplement this method unless your a DIY or bodgit and scarper, its poor practice at the very least and ust because the regs dont specify this particular case dont mean it ok.

Sorry, was this aimed at me? As I said I have found it and not changed it, but I have NEVER installed it!

 

[mogga]

I carried out the new PIR / condition report today and found a diy bodger had added two way light switching, in flex ,using the cpc as a live, in almost every room!

Now I thought code 2, but I cant find any reference to it in the best practise guide. I know it was once upon a time a done thing to use the cpc as a live in two way light switching, but this has been done recently.

I was sure there was a regulation stating that a cpc can never be used as anything but, even if it was sleeved? I can't find it except for single core reference.

411.3.1.1 A cpc shall be run to, and terminated at each point in wiring, and at each accessory.

514.3.2 Every core of a cable shall be identified at its terminations and preferably throughout its length. Sleeves for identification should comply with...

514.4.2 "SINGLE CORE CABLES" that are coloured green and yellow throughout there length shall only be used as cpc and not over marked at their terminations.

But 411.3.1.1 demands an earth anyway so its still wrong even if it were sleeved? I'm trying to recommend the best fix, without destroying every other wall and rewiring, all I can think of is to convert to one way switching with an earth? Although you can have a lighting circuit without a cpc as long as you comply with all the requirements, so do I put a sticker on the consumer unit saying the lighting circuit has no cpc and then sleeve all the live cpc's brown at each termination?

LUTRON do a 2 way that only requires 2 cores I think

 

[RogertheBodger]

yep, H.M.S. Hood, well spotted.
Its old, mighty, English but unfortunately Doomed........

A failing of her class unfortunately, as Beatty said " there is something wrong with our Bloody ships today" ( Historical Quote Mods )

 

[yellowvanman]

514.4.2 "SINGLE CORE CABLES" that are coloured green and yellow throughout there length shall only be used as cpc and not over marked at their terminations.

The ECA's Guide to the 17th Edition, used this wording to assume that you can use a G/Y in a multi core cable for other purposes.

Not good practise though!

 

[Adam W]

I'm with wirepuller and telectrix - the g/y live will be the same csa as the live conductors so provided they have been sized correctly there is no immediate danger present.
If I have understood correctly the rest of the cct has been wired 'normally', just the switching converted to 2 way with an imaginative use of flex, ie the only part of the cct with no cpc is the added switch.

Not how I would have installed it, but I'd give it a C3 if anything.

 

[SPARTYKUS]

Don't forget HMS Repulse, sister ship to the Hood, less known but equally battle cruiser monsterous.

The stories my grandad told me. Japanese suicide bombers burning on the deck in the plane wreckage, all dressed for the funeral when they got in the plane. Not a new idea by any means.

Sorry to OP gone off topic.

 

[netblindpaul]

Please remember that the bare cpc in T&E is not insulated at all, so it can't be used as a live conductor under ANY circumstances.

 

[ruston]

I agree with that , thats why it's twin and earth , three core and earth -because the bare earth is not a core.

 

[PC Electrics]

To my mind, using the g/y in a flex as a live conductor is abhorent. I carry 5 core flex for items such as cylinder stats, timers etc. No excuse not to - it's readily available and not overly expensive.
I come across g/y in flex used as live all the time, so know to watch out for it, but I think it should be disallowed by regs.