meter tails over 10 meters best way to do it

[pablo4321]

Hi just after a bit of advice,we are wiring a new build where the meter is, the tails will be coming from outside into the kitchen they will be coming up the wall to the ceiling along the the middle of the joists to the consumer unit in the wall what is the best way to do this

1) shall i run them in steel conduit and earth the conduit to the earth terminal in the meter.
2) do i need a overcurrent switch fuse in between
3) and is it acceptable to use just normal meter tails to run under the floor in the middle of the joist.


thanks for any advice.

 

[Octopus]

What are your thoughts?

 

[Fast&Rough]

Too early for this! ask again at dinner time when you have moved the d/b

 

[pablo4321]

i was thinking 60 amp fuse switch and run it in conduit metal up in safe zone

 

[telectrix]

or use SWA.

 

[pablo4321]

would you just use 25mm 2 core do i still need to protect where it goes up the wall

 

[telectrix]

if it's buried in the wall, either use SWA, MICC, earthed steel conduit, or RCD protect the tails.

 

[Rockingit]

TBH, you'll find that 16mm/3c is as cheap as 16/2, and why do you need 25mm if you're down fusing to 60 or 80A??

This is a pic of an armoured 16/3 made off into tails for just this purpose - about 10m between intake and CU, where the cable is run exposed internally on the joists.

 

[pablo4321]

thanks rocking it thats looks neat, just another question the bit round the armour where you have earthed it where do you get them from and what they called thanks

 

[KAS1]

That's not a roofing bolt used at the frying pan is it, if so why didn't you use a brass bolt !!!!!!!

 

[Guest55]

That's not a roofing bolt used at the frying pan is it, if so why didn't you use a brass bolt !!!!!!!

and kas1's inspirational contributions to the forum continue with limitless technical insight...........

 

[NadHuh]

Are you not meant to bury tails or run them through joists? Because I've seen this I'm talking about a domestic house where the meter is out side the property in a little hut about 2m away from fuse board but the tails are about 5m and the tails come in to the house go up buried in a wall then through some joist and down to a high level fuse board.

 

[Outspoken]

Oh my, unqualified people making comments on a subject unqualified people have no business playing with and people seeming to ignore the regs that require meter tails to be no more than 3m long, after that they become a sub-main and must be wired in an appropriate manner.

Running tails via conduit is a simple none-starter, so your left with SWA and Pyro. Pyro is clearly outside to price range of all but commercial installs these days in special locations so your left with SWA. Meter tails are required to be 25mm² and for the purposes of common sense I would personally and professionally suggest that the sub-main also be 25mm², regardless of the sub-main being fused down to 60A or 80A. There may come a time when they want a larger supply and so this would need to be rewired if in 16mm², not easy in a finished house.

The correct way to do this would be

Head > Meter > DP Isolator > Sub-main > RCD Main switch in CU

 

[Rockingit]

thanks rocking it thats looks neat, just another question the bit round the armour where you have earthed it where do you get them from and what they called thanks

It's actually just a 20mm conduit coupler!



And I take no credit for this at all, it was an idea that Tony gave to me elsewhere a couple of weeks ago (hence why I happen to have some pics!).

 

[Spoon]

Meter tails are required to be 25mm² and for the purposes of common sense I would personally and professionally suggest that the sub-main also be 25mm², regardless of the sub-main being fused down to 60A or 80A. There may come a time when they want a larger supply and so this would need to be rewired if in 16mm², not easy in a finished house.

Sorry but I don't agree with this. Why should more money be spent on buying 25mm when you should be selecting the cable suitable for the fuse size and installation method. How can you know what is going to happen in the future. Design the circuit to what is there now and not what might be there in 20 years time.