Wall light 3 core cable with no earth

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gezandkaz

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Hi, I am in the process of replacing the wall lights in the living room of our 1973 era bungalow. There are two sets of lights, one either side of the fireplace both controlled by a single wall switch. There is no ceiling pendant light fitting. When I removed the two light fittings I found each one is supplied by a 3 core cable with the following wires. One red, one black and one black with a red sleeve. Live, Neutral and switched live to my basic understanding. There is no earth cable although checking the other light fittings in the other rooms, they all have an earth (green wire). Our light switches are all plastic and were replaced along with the power sockets and the consumer unit last year. All wiring is buried in the wall in metal conduits.
I have obtained Class 2 double insulated wall lights as replacements but my question is this. I assume the switched live (black/red sleeve) and the neutral (black) matches the live (brown) and neutral (blue) on the fitting but what happens to the spare red live wire from the 3 core cable? I assume I place it in a redundant slot on a connector or tape it up. However, assumptions being the mother of all cock ups I thought I'd better ask......
Cheers
Gerard
 
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I think you'd best post a picture, Red and two blacks with no CPC would be a *very* unusual cable. A CPC has been required at every point since the 14th edition regulations came in in 1966, so a '73 house shouldn't have cable without one.
 
Last edited:
I strongly suspect someone sleeved the CPC black and red.
 
Ragnar_AT said:
I strongly suspect someone sleeved the CPC black and red.
Click to expand...
That seems most likely.

My other thought might be pyro
EDIT or even some european 3 phase Brown, black, black. Sometime red and brown can get very close.
 
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gezandkaz said:
Hi, I am in the process of replacing the wall lights in the living room of our 1973 era bungalow. There are two sets of lights, one either side of the fireplace both controlled by a single wall switch. There is no ceiling pendant light fitting. When I removed the two light fittings I found each one is supplied by a 3 core cable with the following wires. One red, one black and one black with a red sleeve. Live, Neutral and switched live to my basic understanding. There is no earth cable although checking the other light fittings in the other rooms, they all have an earth (green wire). Our light switches are all plastic and were replaced along with the power sockets and the consumer unit last year. All wiring is buried in the wall in metal conduits.
I have obtained Class 2 double insulated wall lights as replacements but my question is this. I assume the switched live (black/red sleeve) and the neutral (black) matches the live (brown) and neutral (blue) on the fitting but what happens to the spare red live wire from the 3 core cable? I assume I place it in a redundant slot on a connector or tape it up. However, assumptions being the mother of all cock ups I thought I'd better ask......
Cheers
Gerard
Click to expand...
Can you send photos please?
 
Adam_151 said:
I think you'd best post a picture, Red and two blacks with no CPC would be a *very* unusual cable. A CPC has been required at every point since the 16th edition regulations came in in 1966, so a '73 house shouldn't have cable without one.
Click to expand...
You got a copy of the 16th from 1966?
 
SUNRAY said:
EDIT or even some european 3 phase Brown, black, black. Sometime red and brown can get very close.
Click to expand...
I'm 99% sure that was never a thing. I work with old Euro cables a lot and all I've seen was brown - black - blue, with or without green/yellow. In the early 2000s that changed to brown - black - grey, although the old version is still available too (many European countries' regs require neutrals to be identified blue along their entire length). Only five-core (with earth) and four core (no earth) had two blacks in the old colour scheme. That's not to say no European country ever had 3-core cables with brown - black - brown but I doubt it because there wouldn't have been any way of distinguishing between the two blacks. In 5-core the position in the cable lets you tell them apart, one is between green/yellow and blue, the other between brown and green/yellow.

So I'm fairly sure it's old-colours T&E and some numpty abused the CPC as a switched live. Reminds me of a Youtube video from Poland where someone rewired a flat and found that someone had wired the whole thing in UK T&E, including a 2-way circuit without even bothering to sleeve the bare CPCs now used as strappers. Good thing back boxes on the continent are all plastic!
 
TimboTwo said:
You got a copy of the 16th from 1966?
Click to expand...
D.6 At every lighting point an earthing terminal shall be provided and connected to the earth-continuity conductor of the final sub-circuit.
However even before that the earth was only permitted to be omitted if (ix) Lighting fittings using filament lamps installed in a room having a non-conducting floor, mounted at such a height that they cannot readily be touched and are out of reach of earthed metal. There were other conditions, but it means that wall lights needed an earth going back to at least 1955 or 13th edition.

However by time I found out Buttler's the builder who built may parents house were no longer around, and since we should get an EICR every 10 years (less with rented) we can't really go back any further.

Today it says well in my 2008 edition "A circuit protective conductor shall be run to and terminated at each point in wiring and at each accessory except a lamp holder having no exposed-conductive-parts and suspended from such a point."

One assumes this only applies to low voltage? Clearly with extra low voltage we have SELV where we should not have an earth.
 
Why would you need a permanent live and switched live at the light anyway?

Can you find the other end of the cables to the two lights, either at the switch or in the loft? If so, you can check how they're connected at the other end and possibly change that to neutral, switched live and earth, adding some green/yellow sleeving in the process.
 
Ragnar_AT said:
I'm 99% sure that was never a thing. I work with old Euro cables a lot and all I've seen was brown - black - blue, with or without green/yellow. In the early 2000s that changed to brown - black - grey, although the old version is still available too (many European countries' regs require neutrals to be identified blue along their entire length). Only five-core (with earth) and four core (no earth) had two blacks in the old colour scheme. That's not to say no European country ever had 3-core cables with brown - black - brown but I doubt it because there wouldn't have been any way of distinguishing between the two blacks. In 5-core the position in the cable lets you tell them apart, one is between green/yellow and blue, the other between brown and green/yellow.
Click to expand...
Some countries used brown, black,black as 3ph and still saw this format as recently as 2019 being installed in Spain.
Ragnar_AT said:
So I'm fairly sure it's old-colours T&E and some numpty abused the CPC as a switched live.
Click to expand...
FWIW I assume, like you, it is old colour T&E but I don't know why it's being assumed it's the switched live
Ragnar_AT said:
Reminds me of a Youtube video from Poland where someone rewired a flat and found that someone had wired the whole thing in UK T&E, including a 2-way circuit without even bothering to sleeve the bare CPCs now used as strappers. Good thing back boxes on the continent are all plastic!
Click to expand...
 
We have all seen where plumbers have used the earth as line with tank thermostats with a Y Plan. But at the end, one has to test and inspect to find out what is what, and we can't do that on a forum.
 
ericmark said:
We have all seen where plumbers have used the earth as line with tank thermostats with a Y Plan. But at the end, one has to test and inspect to find out what is what, and we can't do that on a forum.
Click to expand...
I've even seen T&E used as 3 phase.
 
It is not that long ago that 5 core flex sold here (probably with the European market in mind though) had Brown, Blue, G/Y for E, and two blacks originally for phase 2 and phase 3 in some countries.

So if used like that rather than the two blacks being for control purposes for stats or overrun etc then I was always conscious of European 3 phase conductors having say 415/400V between them. I thought our (at that time) Red/Yellow/Blue for phases to be more idea lor even B rown Black Grey although I have never liked Brown Black Grey so give me RYB or even the older R W B anyday.
 
I too have a copy of the 14th and it does indeed introduce an ecc to lighting circuits (amongst other things) from '66.
 
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