Would 10mm tails be acceptable?

[HappyHippyDad]

I will be fitting a henly block to split the meter tails. I'll be taking some tails 1-2m a new shower consumer unit (63A RCD and 45AMCB) with no spare ways to fit extra MCB's. I'm not sure what the cutout fuse size is.

I was planning on using 16mm tails but would 10mm tails be acceptable?

Regulation 433.3.1 (ii) states that over current protection need not be provided in this example.

 

[Nigel]

Yes that is ok.

 

[Bobster]

Nothing against doing that.

Do you have 10mm tails just lying around though. Surely be cheaper if you use 16mm as it's a more common size?

 

[HappyHippyDad]

Nothing against doing that.

Do you have 10mm tails just lying around though. Surely be cheaper if you use 16mm as it's a more common size?

Just rang the wholesaler. No 10mm tails, so I'll go for 16mm!
Thanks for the reply though Rob
edit... Thanks also Essex, didn't see your concise reply below mine!

 

[Bobster]

Just rang the wholesaler. No 10mm tails, so I'll go for 16mm!
Thanks for the reply though Rob

I did wonder, I've never seen any before.

 

[HappyHippyDad]

I did wonder, I've never seen any before.

This site seems to have all sorts Earth 6181Y Tails Cable | Meter Tails Cable | The Electric Cable Company (GB) Ltd - https://www.electriccable.co.uk/RWD6181ytailsTECC.php
I use it to compare prices and then knock down my local wholesaler. I saw all the different size meter tails and assumed (incorrectly) most other places would stock it.

 

[Strima]

I did wonder, I've never seen any before.

We use them quite a lot on un-metered supplies jumped off street lighting circuits.

 

[DPG]

We use them quite a lot on un-metered supplies jumped off street lighting circuits.

For caravans?

 

[Strima]

For caravans?

If there's Daags present...

 

[freddo]

Used some 10mm tails on a really small installation. The complete installation was 2x 2' LED sign lights. Seemed pointless putting in anything larger. DNO didn't care when they made the connections.

 

[Octopus]

shhhhhhhhhhhhhhh

don't discuss this or the authors of the OSG will be having kittens...

 

[Ian1981]

shhhhhhhhhhhhhhh

don't discuss this or the authors of the OSG will be having kittens...

The Fact they state 25mm minimum in the OSG must be because they have no faith in an electrician actually working out the CSA required
It’s too much to ask on a 18 day course

 

[DefyG]

I've never seen any before.

Really? ...... thought they were quite common for the example given by the OP.

 

[123]

I did wonder, I've never seen any before.

Easy enough to get this side of the pond, my local wholesaler keeps 6mm, 10mm, 16mm etc on the shelf. I carry small amounts of each in the van. And can't recall the last time I used 25mm tails, 16mm is more the norm here.

 

[Zerax]

The Fact they state 25mm minimum in the OSG must be because they have no faith in an electrician actually working out the CSA required
It’s too much to ask on a 18 day course

You want to see a plumber try to 'gas rate' an appliance !!

 

[Deleted member 26818]

They used to be acceptable, but now, BS7671 doesn’t even list the CCC for 10mm2 in free air.

 

[DefyG]

[

 

[Deleted member 26818]

[

Multicore.

 

[DPG]

Where's that post gone?

 

[DefyG]

Dunno, what I was try to suggest was that as they are almost always installed as a line and a neutral 'touching' they are effectively a 2core cable (albeit no overall sheath) and therefore it wouldn't be unreasonable to apply table 4D2A ccc of 70A in free air.

 

[Bobster]

Really? ...... thought they were quite common for the example given by the OP.

I don't do domestic work. So no, not seen them before.

 

[Dave OCD]

Can anyone else remember using 6mm tails looping out of a Wylex board main switch to supply a new 1 way board for a shower? [Or other additional circuit]

 

[MFS Electrical]

If there's Daags present...

D’you like daags?

 

[MFS Electrical]

Can anyone else remember using 6mm tails looping out of a Wylex board main switch to supply a new 1 way board for a shower? [Or other additional circuit]

Never done it myself always thought it was a bit rough to be fair but it was quite a common occurrence round these parts.

 

[davesparks]

Can anyone else remember using 6mm tails looping out of a Wylex board main switch to supply a new 1 way board for a shower? [Or other additional circuit]

Am I right in thinking wylex boards had dual incoming terminals for exactly that purpose once upon a time?

I'm sure I've seen this on really old boards.

 

[freddo]

Some Wylex fuseboards had the 'extenso' terminals after the main switch, plenty of the Wylex 60a switchfuses certainly had dual incoming terminals.

 

[Dave OCD]

Am I right in thinking wylex boards had dual incoming terminals for exactly that purpose once upon a time?

I'm sure I've seen this on really old boards.

I've seen that Dave but rarely, more common to see the far left of the busbar [furthest away from the main switch] with terminals at the bottom the same as the outgoing 'ways' - you could loop from this and the neutral bar to an 'Extenso' unit as Freddo mentioned and this would just be an enclosure with a couple of fuse carriers isolated by the original main switch.