Consumer meter tail length and size?.

27 Mar 2007
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United Kingdom
I am having an extension on the side of my house and the meter box has to be moved to the new outside wall. The current tails from the meter to the cu is 10mm thick and about 2M long. When the meter is moved it will be about a 10M run to the consumer unit, will 16mm tails be sufficient or will it need 25mm tails?

cheers if anyone can help.
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The majority of DNOs won't like 10m tails, stick a switchfuse where the tails (25mm²) come through the wall, then an appropiate size of SWA for your submain (likely to be 25mm² to your CU)

Or just have CU relocated
"10mm thick" is not the same as 10mm sq conductors.

But tails are usualy run in 25mm sq these days as it is safe for 100Amp (subject to installation method)
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sorry i didn't mean 10mm sq tails they are 16mm sq. I want to keep the cu in the original place inside the house? Is this any clearer? Is there a rule for how long the tails sholud be?
As short as possible, and shorter than the DNO's maximum length ;)

As Adam has mentioned, a switch fuse will probably be required, but you need to check this with the DNO. Also fit 25mm² tails regardless.
Thanks fella's 25mm sq tails it is to swith fuse and swa to cu. thanks again! :D

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