Unusual Neutral Tail into Consumer Unit

[vwes59]

Hi,
Ignoring the appauling conductor terminations which I found, in the background of the photo you can see a really odd neutral tail terminated into the main switch.

I've never seen this before, has anyone else, and if so what is it ? Oh I should add this is at a flat, so the tails are presumably coming from an central electrical cabinet. Flats were built in 2008.

It's part of an EICR, and I'm not even sure how to code it. Going to send it to Napit too, see what they think.

 

[snowhead]

You'll also note the "Odd" CPCs from that cable as well.
Split concentric.

 

[MJPD29]

As above, split concentric cable. Very common here.

 

[brianmoooore]

Common in the UK as well. Used by DNOs for TN-S supplies, and its closely related cousin, concentric, is used for TNC-S supplies.
I've regularly used it for distribution to sub boards as well, but only where installation conditions don't require RCD protection.

 

[James]

I cant believe how short the stripped ends are. wow!!

 

[davesparks]

It's part of an EICR, and I'm not even sure how to code it.

No code, the fact that the person doing the inspection is not familiar with common cable types is not a fault with the installation.

 

[Penguin]

Hi,
Ignoring the appauling conductor terminations which I found, in the background of the photo you can see a really odd neutral tail terminated into the main switch.

I've never seen this before, has anyone else, and if so what is it ? Oh I should add this is at a flat, so the tails are presumably coming from an central electrical cabinet. Flats were built in 2008.

It's part of an EICR, and I'm not even sure how to code it. Going to send it to Napit too, see what they think.View attachment 110835

I’ve seen this before where the installer hadn’t enough 25csa tail, so Connected multi singles to achieve the required result.

Very poor practice as, I’d always recommend sleeved Ferrules.

 

[brianmoooore]

This isn't 'multiple singles', it's the individually insulated neutrals arranged coaxially around about the central live conductor, along with the bare earth conductors.

 

[nicebutdim]

I’ve seen this before where the installer hadn’t enough 25csa tail, so Connected multi singles to achieve the required result.

Very poor practice as, I’d always recommend sleeved Ferrules.

What sort of ferrule would you recommend for the multiple cores of a split concentric cable?

 

[Penguin]

This isn't 'multiple singles', it's the individually insulated neutrals arranged coaxially around about the central live conductor, along with the bare earth conductors.

Please send me a picture as I love to see it.

 

[nicebutdim]

Please send me a picture as I love to see it.

There are images posted to this very thread.

 

[brianmoooore]

See snowhead's post #2
....

 

[Penguin]

You'll also note the "Odd" CPCs from that cable as well.
Split concentric.

View attachment 110841

WOW, surely this is a DNO type requirement cable on a TT.????

There’s NO armoured, and I take it that the silver wrap is flimsy foil.????

I can’t imagine my wholesaler supplying this.

Are you in the UK.??

 

[brianmoooore]

Widely available in the UK.
It's not armoured, but it's extremely unlikely that a metallic object could penetrate it and make contact with the live conductor without shorting it to the neutral or earth .
The 'foil' is plastic, not metallic.

 

[Penguin]

Widely available in the UK.
It's not armoured, but it's extremely unlikely that a metallic object could penetrate it and make contact with the live conductor without shorting it to the neutral or earth .
The 'foil' is plastic, not metallic.

Thanks for the reply. Can you please give me an example of where you’d consider using it. ???

 

[MJPD29]

I’ve seen this before where the installer hadn’t enough 25csa tail, so Connected multi singles to achieve the required result.

Very poor practice as, I’d always recommend sleeved Ferrules.

This isn’t multiple singles. This cable is made this way, so this isn’t bad practice. If you Google split concentric cable it’s a very common cable type, neutral and earth are multiple cores with live through middle as one core.

 

[MJPD29]

Thanks for the reply. Can you please give me an example of where you’d consider using it. ???

Specced on council street lighting contract that we were on for years. But can be used for feeding consumer units etc if installation method allows.

 

[davesparks]

WOW, surely this is a DNO type requirement cable on a TT.????

No use for a TT supply as it has an earth in it.
Split concentric is used by DNO's for TN-S supplies but is also available for use in normal installations.

There’s NO armoured, and I take it that the silver wrap is flimsy foil.????

No there isn't an armour, but you wouldn't use it in a situation where an armour is required.
Obviously it can't be used for direct burial in an installation but is perfectly fine clipped direct, on cable tray, in risers etc.

This cable is widely used in blocks of flats for the BNO network, usually the orange LSF version of it.