Running T&E cable outside

[ilikewatchingtv]

Hi all,

While browsing the following thread:

//www.diynot.com/forums/electrics/adding-plugs-to-loft.295787

I noticed that the advice from a couple of well respected posters was that T&E cable is unsuitable to run outside. I currently have both lighting and ring cables running outside along the wall of my kitchen and along a garden wall to supply my outhouse. The cable appears to be "relatively" recent - it's PVC sheathed unlike some of the live lead and paper cables I found when renovating the house itself.
My question is whether this cable should be urgently replaced, or whether as an existing installation it is ok being left for the moment? I must add that I have never had any problems with the circuits in the outbuildings and the exterior cables seem to be undamaged other than the many accumulated layers of paint on them.

 

[ban-all-sheds]

If it's OK and undamaged etc, I wouldn't class it as urgent.

Leave it until the weather gets better, and in the meantime be careful not to jab at it with anything sharp.

 

[ilikewatchingtv]

If it's OK and undamaged etc, I wouldn't class it as urgent.

Leave it until the weather gets better, and in the meantime be careful not to jab at it with anything sharp.

Thanks - it's been on my list of things to get sorted for a while, will leave it till next summer when I get some quotes for other electrical works and include it at those!

 

[martinxxxxxx]

I spoke with prysmian cable's help desk recently and asked them for a definitive answer on the suitability of this type cable for outside use and they were adamant that used correctly it was suitable,

Personally I would not install it as there are much better cables around these days which have higher tolerance to UV exposure.

I only phoned them in the hope of getting something concrete to back up my opinion that the cable was not suited but I was forced to retreat on this.

I still don't like to see it used but there you go.

Martin

 

[JohnW2]

I spoke with prysmian cable's help desk recently and asked them for a definitive answer on the suitability of this type cable for outside use and they were adamant that used correctly it was suitable, Personally I would not install it as there are much better cables around these days which have higher tolerance to UV exposure.

I'm actually not convinced that it ever was quite as big a problem, UV-wise, as people seem to believe...

...a little while ago, I took the oppotunity of the presence of some scaffolding to remove a length of (unpainted) Imperial T&E which has been (unused) high up on one of my outside walls (mainly on a SE-facing one) for at least as long as I've been here (25 years), probably a fair bit longer. It looked fine, still seemed to be very flexible (and I could not persuade it to crack, descpite trying quite hard) and still had an immeasurably high IR (>500MΩ at 1000V).

Whilst, like you, I personally would not use unprotected T&E outside these days, I do wonder how 'unsuitable' it really is, provided it is somwehere where it's fairly safe from mechanical damage. However, maybe Imperial cable was fairly non-susceptible to UV, followed by some early metric stuff which was susceptible, with the pendulum now swinging back in the non-susceptible direction.

Kind Regards, John

 

[NewOrder]

Our security light outside is wired in T&E but its clipped under a porch type ceiling (hard to describe) so isn't exposed to any ultraviolet rays.

I would replace it but that brings up other issues with notifying the work etc.

 

[JohnW2]

Our security light outside is wired in T&E but its clipped under a porch type ceiling (hard to describe) so isn't exposed to any ultraviolet rays. I would replace it but that brings up other issues with notifying the work etc.

Unless I'm missing something (although it wouldn't be the first time I'd done that ), "replacing a damaged cable for a single circuit" is not notifiable, even if outdoors - and I'm sure the reflected UV will have done some damage, aren't you?

Kind Regards, John.

 

[westie101]

We've been using PVC double insulated singles for overhead wiring since it was first on the market. Never seen any warnings about unsuitability or seen any problems with it being exposed to all weather conditions.

As we would expect a minimum of 50 years from assets I would suggest the caution is mere supposition. Or did it come about from the early days of PVC when no one knew if it would last and has just stuck around within the industry?

 

[JohnW2]

We've been using PVC double insulated singles for overhead wiring since it was first on the market. Never seen any warnings about unsuitability or seen any problems with it being exposed to all weather conditions.

Interesting - but,as you will realsie from what I said, not a great surprise.

As we would expect a minimum of 50 years from assets I would suggest the caution is mere supposition. Or did it come about from the early days of PVC when no one knew if it would last and has just stuck around within the industry?

Maybe, but it could have arisen by (unnecessary) extrapolation from other types/grades of PVC. There seems little doubt that some PVC (like cheap hospipes) doesn't like 'eposure' (whether that be UV, heat or frost, or a combination thereof) at all!

Kind Regards, John.

 

[ban-all-sheds]

We've been using PVC double insulated singles for overhead wiring since it was first on the market. Never seen any warnings about unsuitability or seen any problems with it being exposed to all weather conditions.

Black, I expect?

 

[bernardgreen]

When the PVC twin and earth cables to garage and outside lighting was removed from the exterior walls of a house near here some was in "good" condition while other was clearly past its best. These were running side by side and had the same exposure for about 30 year. I assume they were different makes and different grades of PVC.

 

[westie101]

Black, I expect?

No standard Grey/live or neutral as would be used for meter tails etc. Black single insulated was only used for some earthing arrangements of for overhead line conductors