Using earth as neutral

[westward10]

Never heard of tri-rated flexible cable. There are rubber cables available in that size and if it is a long run someone has made a serious error.

 

[Deleted member 26818]

Now that we know its not actually tri rated cable yes, ladder or tray seems more likely.

There's an interesting debate to be had on whether it is ever allowed, for SWA or anything else.

Don’t understand why there’s any debate?
521.5.1 Ferromagnetic enclosures: electromagnetic effects
The conductors of an AC circuit installed in a ferromagnetic enclosure shall be arranged so that all line conductors and the neutral conductor, if any, and the appropriate protective conductor are contained within the same enclosure.
Where such conductors enter a ferrous enclosure, they shall be arranged such that the conductors are only collectively surrounded by ferromagnetic material.
These requirements do not preclude the use of an additional protective conductor in parallel with the steel wire armouring of a cable where such is required to comply with the requirements of the appropriate regulations in Chapters 41 and 54. It is permitted for such an additional protective conductor to enter the ferrous enclosure individually.

 

[rapparee]

Never heard of tri-rated flexible cable. There are rubber cables available in that size and if it is a long run someone has made a serious error.

It's called tri-flex


It's also mechanically strong.

I one time drove a genie MEWP over a live 50mm 5 core flex.

 

[PEG]

It's called tri-flex


It's also mechanically strong.

I one time drove a genie MEWP over a live 50mm 5 core flex.

I bet it looked like a snake,run over,on a cattle grid....

 

[Ian1981]

We’ve pulled in a 185 cable just and realised that we need a neutral. It has 4 cores, brown, black, grey and earth. Can we use the earth as a neutral if we shrink wrap it with neutral sleeve and then run an earth separate? It’s a tri-rated cable, so no armoured to use as earth.

If the cable is installed in some kind of metallic containment then use the containment as the cpc, size permitting of course.
S=K1/K2 x S/2

 

[loplug]

Don’t understand why there’s any debate?
521.5.1 Ferromagnetic enclosures: electromagnetic effects
The conductors of an AC circuit installed in a ferromagnetic enclosure shall be arranged so that all line conductors and the neutral conductor, if any, and the appropriate protective conductor are contained within the same enclosure.
Where such conductors enter a ferrous enclosure, they shall be arranged such that the conductors are only collectively surrounded by ferromagnetic material.
These requirements do not preclude the use of an additional protective conductor in parallel with the steel wire armouring of a cable where such is required to comply with the requirements of the appropriate regulations in Chapters 41 and 54. It is permitted for such an additional protective conductor to enter the ferrous enclosure individually.

So you could remove the ferrous gland plate and replace it with a non ferrous material

 

[rapparee]

I bet it looked like a snake,run over,on a cattle grid....

Didn't take a fidge out of it.

It's extremely robust. You can hardly strip it with a Stanley knife let alone damage it.


There's actually wool between the inner cores and the outer sheath.

 

[PEG]

Didn't take a fidge out of it.

It's extremely robust. You can hardly strip it with a Stanley knife let alone damage it.


There's actually wool between the inner cores and the outer sheath.

....Your personal sex life,is not any of our business....

 

[happysteve]

We’ve pulled in a 185 cable just and realised that we need a neutral. It has 4 cores, brown, black, grey and earth. Can we use the earth as a neutral if we shrink wrap it with neutral sleeve and then run an earth separate?

Yes. I can't see any Regs that preclude this.

 

[EalingBadger]

Worth a read, I think:

Using Green/Yellow not as CPC - https://www.electriciansforums.co.uk/threads/using-green-yellow-not-as-cpc.35860/

Strictly speaking it would seem that over-sleeving is okay, but personally I'm on the side of those that would never do it - mostly due to the element of unexpected surprise that somebody maintaining the installation in the future might be confronted with.

 

[Pete999]

Never heard of tri-rated flexible cable. There are rubber cables available in that size and if it is a long run someone has made a serious error.

Agree

 

[Deleted member 26818]

Worth a read, I think:

Using Green/Yellow not as CPC - https://www.electriciansforums.co.uk/threads/using-green-yellow-not-as-cpc.35860/

Strictly speaking it would seem that over-sleeving is okay, but personally I'm on the side of those that would never do it - mostly due to the element of unexpected surprise that somebody maintaining the installation in the future might be confronted with.

It’s ok to sleeve the CPC in a multi core cable, but not if it’s a single core cable.

 

[EalingBadger]

It’s ok to sleeve the CPC in a multi core cable, but not if it’s a single core cable.

I know.

I still don't like it though.