Help identifying a cable

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I have a twin and earth cable which is stranded for all 3 wires. The earth has 3 strands. Does that tell you what size cable it is?

Thanks in advance.
 
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In modern UK T&E conductors up to 2.5mm² are solid, while 4mm² and large conductors are stranded. In larger T&E the earth is nearly always two sizes smaller than the current carrying conductors. Therefore:

2.5mm² and smaller modern UK T&E has all conductors solid.
4mm² and 6mm² modern UK T&E has stranded live and neutral condutors but a solid earth conductor.
10mm² and 16mm² modern UK T&E has all conductors stranded.

However all the pictures I can find of 10mm² show an earth conductor with more than three strands.

Therefore I think your cable is likely either an old imperial cable, or a foreign cable that someone has imported.
 
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Is my best bet to match up based on overall width of cable?
 
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I have a twin and earth cable which is stranded for all 3 wires. The earth has 3 strands. Does that tell you what size cable it is?
As sparkwright has said, its the CSA of the conductors which matter. Do you have a micrometer or vernier gauge with which you could measure the diameter of one of the strands fairly accurately?

Kind Regards, John
 
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Sorry for the poor image
40C5F38B-9CFE-4DEB-ACB5-38F60A2EF422.jpeg
 
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Looks like 7/029 imperial cable. Red and black 7 strands, earth 3 strands.
That sounds like the one. Good find!

Do you know what that means for metric cable sizes? Trying to determine the breaker size.
Thanks again.
 
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Correct, its to be treated as 2.5, but in reality its really closer to 3.

Stranded 2.5 twin is/was available, but the giveaway was this still had a solid 1.5 earth, so the 3 strand earth suggests 7/.029 (2.98mm²) with a 3/.036 cpc(1.97mm²) (the first number is the number of strands, the second number is the diameter in inches)

Secure alludes to whether it is tinned or not, yours is untinned copper as tinned would have a silver/grey appearance. Earlier cables were tinned, and generally imperial T/E would be, but a small amount of later stuff wasn't. I'm presuming that at some point they realised it was unncessary with PVC (but had been required with VIR). That would put the age of the cable as about 1968-1970. Any odlder and it would be tinned, any newer and it would be metric (but with a 1mm cpc, untill 1980)
 

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