twin and earth used outside

[Sidewinder]

Ash,

Wikipedia is not always spot on mate.

You are correct that standard pvc sheathed T&E is no longer considered suitable for use outdoors where exposed to uv radiation and temperature fluctuations such as would be experienced in this environment.

However, Specs is also correct in that it does last about 20+ years or at least the old stuff did!

 

[Ash]

no, it's more Specs has on a number of occasions started arguments with me without ever getting factual backup.

 

[M107]

Well I've used all the following options on various occations, for dropping cable from upstairs to down stairs or external in to conservatories:

• T/E (not my preffered method but nothing to stop it's use so long as conditions allow it's use no problem)
  
• Hituf cable (this I've used many time & isnt overly unsightly & only requires nylon glands again not unsightly)
  
• SWA (again used many times, mainly when extending externaly around a building into conservatories)
  
• Tube (not a bad option but use black white stands out big time, boxes at either end look bulky to the eye so ask customer first)
  
• Trunk (galv or pvc, used a couple of time but it needs to go out of sight as much as possible, looks pants on the front of domestic property)
  

Hituf is my cable of choice for what you are wanting to do.

 

[PC Electrics]

For those that say t&e should never be used on an outside wall, I refer you to the IEEs OSG, appendix 3, table 3A which may be found on page 106.

It is certainly true that direct exposure to natural UV (sunlight) will shorten the expected lifetime of pvc sheathed cale. It's working life, if undisturbed, should nevertheless extend well beyond 20 years even when used in this way in the UK. This is considerably shorter than its normal expected life of 100+ years when installed inside a house.

t&e installed on an outside wall may be painted to help protect it from the effects of UV. I have found Plasti-Kote enamel in nut brown to be highly effective on brickwork.

 

[SPECIAL LOCATION]

you're just out to argue with me aren't you?Twin and earth - Wikipedia, the free encyclopedia

2 seconds in google

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still trying to find that regulation number btw?

no, it's more Specs has on a number of occasions started arguments with me without ever getting factual backup.

Oh dear....

it is worrying when some "electricians" consider a Wikipedia search referencing

1.^ Fritz, Wilfred (2008). Electrical principles and practice. Cape Town: Pearson. pp. 363. ISBN 9781770250710.

Which is a publication to "SOUTH AFRICAN BUREAU Of STANDARDS" as.....

As a factual reference for UK electrical wiring to BS7671!

perhaps if some people take longer than 2 seconds doing internet searches and actually read the hard copy BS7671 they would find the correct information they require!

As PC Elec has already stated try On Site guide Page 106..

OR

Guidance Note 1 "Selection & Erection" page 166..

I personally find them more applicable to my work in the UK to BS7671....

Others are entitled to disagree with that opionion..

but I would NEVER suggest any student reading this site considers an uncorroborated Wiki link to be more applicable than BS7671 and its guidance notes..

As said earlier your statement that PVC T&E should NEVER be use outside is..

Factually Incorrect!

:C

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Just to add I have no doubt that Ultra violet rays will reduce the lifespan of a PVC cable and I would also agree that

Ultra Violet rays in South Africa are on the balance of probabilities a smidge higher that what we get here in good ole blighty!!

If you read a bit more of page 166 guidance note1 it can even on occasions be use on overhead wiring between buildings with appropriate support...

thats got a bit more UV exposure in book book than on a wall!!

:coffee

 

[Manator]

Remember gentlemen, debate is the difference between one veiw against another, and not about personal dislikes. Referance material provided will always improve your argument, as will statements of fact. Interpretation of any regulation is subject to the person interpreting them, if everything was black and white, we would not even need a discussion forum.

I like friendly, sometimes heated, but respectful debate. Just like this forum aims to acheive.

 

[Essex]

What about Hi-tuff?

 

[M107]

What about Hi-tuff?

^5

 

[onsiteguide]

I thought that T+E couldn't be used outside because of the uv rating and that degrades the cable causing it to crack and split? but like most of the time i stand to be corrected.

 

[Voltimax]

Well just to throw my hat in the ring........

I like to rely on a thing called "experience". I once worked as a maintenance electrician at Bernard Matthews. We had sheds there where the internal fans were wired in T&E, but the cables were clipped on the outside of the sheds. I can tell you now that the T&E was not in good shape at all. One thing that happens is that the clips become brittle and eventually break, thus the cable sags and stretches to a degree. Even though the cable sags, in the summer heat it stiffens and cracks slightly, also where water has come into contact with it, it turns green. What started out as nice neatly clipped cables ends up looking like varicose veins.

I have also seen many examples of T&E used as an overhead supply taped or tie wrapped to a catenary wire. Again the cable doesn't look healthy, and loses some of it's pliability. Many people seem to think T&E is water proof, but I have seen many examples to suggest otherwise. The amount of times I've been called out to an outside supply tripping and I've isolated the problem to be the supply cable. The cable being run in alkathene pipe which has become full of water due to open ends. When the cable comes out it's like the sheath is full of small holes and parts of the cable are black where the trip has been reset time and time again only to damage the cable further. I've seen this many times on bore pump supplies.

Based on my own experience, I don't like to see T&E outside and I try never to install it that way. Emphasis on the word TRY though

I would never ever rely on Wikis to tell me how to do my job though :red card

It's funny the Americans have a similar cable called "Romex" and under their "Code" (regs) they're not allowed to run it unprotected as we do.

 

[batty]

I prefer to use flex clipped outside if its a shortish run but really don't like to see cables outside full stop but at times they have to be.

 

[SPECIAL LOCATION]

I prefer to use flex clipped outside if its a shortish run but really don't like to see cables outside full stop but at times they have to be.

Agreed..

in 90%+ situations its just a mater of careful design and plan so that entry to accessories / boxes is directly through the wall behind the item...

Also.. we should not forget that there are many "external" situations where the effects of solar influences are minimal to say the least....

consider;

a house with an open side, open end, car port.

a property with large overhanging eaves.

a group of terrace properties with an open passage between them to access rear gardens.

a four walled property (with a roof), where not all of the external walls are in direct sunlight.

etc..

etc...

A cable run "outside" in any of these areas could last for many years without any signs of UV damage.

But as batty says if its going to look ugly.....

and on some walls due to uneven nature of the brickwork / render / crap builders..

it is often best to not waste your time trying to clip T&E along a major uneaven surface.

 

[Apache]

Referance material provided will always improve your argument,

That depends a lot on what you refer too!

 

[Evans Electric]

It appears to last quite well when out of direct sunlight .

I've found some under floors where the plastic has hardened and all flexibility gone , perhaps cheapo or dodgey cable , its usually metric solid strand and not older stranded imperial .

 

[Ash]

flamed for the wiki link, i'll now explain. It was the first result in google. I could have looked further and found something more reliable, but why, it's common knowledge about the sun exposure. just unlike Special, I like to somewhat back up any argument I have even if it involves wiki, but then again I don't start arguments for the point of starting them.

But special, if you like to use T+E outside

headbang :C

bad practice..

poor atitude IMHO..

 

[Doc Hudson]

flamed for the wiki link, i'll now explain. It was the first result in google. I could have looked further and found something more reliable, but why, it's common knowledge about the sun exposure. just unlike Special, I like to somewhat back up any argument I have even if it involves wiki, but then again I don't start arguments for the point of starting them.But special, if you like to use T+E outside

headbang :C

bad practice..

poor atitude IMHO..

Ash, I am unclear why you suggest the forum has members flaming? The thread has some debate on two opinions about the use of T&E outdoors. You are entitled to your view that it is bad practice. However as various members have suggested using an internet link to material as guidance in other countries, is not helpful to any of our younger members who use this site to help them learn about UK electrical wiring practice. This forum is about UK wiring and not World electrical practice. From what I see both PC Electrics and Special Location have referenced UK wiring practice documents to back up their opinion. As such, I consider thier reference material more applicable for a student, or a time served spark, than your link toward this debate. It is a hazard in many trades today, that inexperienced people take a quick internet link and treat it as 100% fact, without cross checking any reference sources. Accuracy is always preferred over speed IMHO.

Doc H.

 

[mikep]

See it used all the time and the onsite guide implies you can use it but I think it degrades too much and so do the clips so pop a bit of conduit up and clip it well.

Mike.

 

[martinxxxxxx]

If fact the (16th Ed) OSG in appendix 3 says T&E is generally suitable "on exterior surface walls, boundary walls and the like"with just a comment that protection from sunlight may be necessary.

Personally I would NEVER use it. I would come out into a extrior JB and back fill the hole with gripfill. Do the same with the other cable and bridge between with NYY (HiTuff) in black.

I am not sure why you don't just leave this on the downstairs circuit though?

Martin

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OOPs yes I do bad IR reading

 

[dazzel]

tiwn & cpc has no uv protection the cheap opshion would be flex with rcd

 

[kme]

I`m not going to get TOO involved in this debate.....I will simply say that I don`t particularly like using FTE outside. That doesn`t mean it isn`t allowed, just that my personal preference is not to do it.

Ash: could I nicely / politely / without causing offence suggest winding your neck in a little? The point about the wiki page being written, and with reference to, other countries was a valid one. SpecLoc has, over the years, demonstrated his knowledge and capability, to the majority of members. If you have a serious problem with him, and his posting attitude, the forum does provide a system to "ignore" certain members, and their posts.

I didn`t see you as being "flamed", it appeared to be more of a correction. The point about using BS reference material, rather than a "ten second" search of the internet, wasIMO a valid one. Perhaps some people get upset when an error is pointed out to them?