"Electrical cables have a life, 15 to 20 years."

[mattg4321]

Quote from the president of the chartered institution of building services engineers.

See below.

http://www.bbc.co.uk/news/uk-politics-35749075

Agree or disagree? Seems like a rather sweeping generalisation to me. I'd be interested to hear from those on here that might've had a role in maintaining historic buildings such as the Houses of Parliament. I refuse to believe they rip out cabling that is perfectly serviceable just because of an arbitrary time limit?!

I seem to remember learning about the lifespan of cables at college, quite a few years back now so I'm struggling to remember. 20 years does ring a bell - but I'm sure that was if it was run continuously at full operating current and temperature? Admittedly most of my work is small commercial/small industrial/domestic but I'm sure I've not come across many cables running at 70 degrees continuously.

So what do we think? I might be way wide of the mark but I would've put money on it that the HoP have some cables still in service that are a multiple of 3/4+ of 20 years in service. Is this guy just a massive jobsworth?!

 

[KWCFC]

What cables though? I'm sure there's a few on here who would disagree where pyro is concerned

 

[sparksburnout]

When I had my last assessment (Stroma) the guy told me that if a house has cabling (so T&E) over 30 years old it needs ripping out and replacing, regardless. No IR tests, just replace. Bollox if you ask me. As far as I am aware 1) The actual copper never deteriorates, it is purely the insulation, 2) The condition of the insulation is totally dependant on the operating temperature over time and it can either be knackered or as good as new. The only way to tell is to test it?

 

[KWCFC]

Sounds like the commonly used cowboy line "Your wiring is the old colours mate, you need a rewire"

 

[Pete999]

Quote from the president of the chartered institution of building services engineers.

See below.

http://www.bbc.co.uk/news/uk-politics-35749075

Agree or disagree? Seems like a rather sweeping generalisation to me. I'd be interested to hear from those on here that might've had a role in maintaining historic buildings such as the Houses of Parliament. I refuse to believe they rip out cabling that is perfectly serviceable just because of an arbitrary time limit?!

I seem to remember learning about the lifespan of cables at college, quite a few years back now so I'm struggling to remember. 20 years does ring a bell - but I'm sure that was if it was run continuously at full operating current and temperature? Admittedly most of my work is small commercial/small industrial/domestic but I'm sure I've not come across many cables running at 70 degrees continuously.

So what do we think? I might be way wide of the mark but I would've put money on it that the HoP have some cables still in service that are a multiple of 3/4+ of 20 years in service. Is this guy just a massive jobsworth?!

Jobsworth and I was a civil servant so I know all about jobsworths

 

[davesparks]

Everything manufactured has to be given a rated lifespan, cables are generally given 20years of constant use at full rated current.

 

[Andy78]

What a load of cobblers. As we all know, only testing can indicate the condition of a cable.

I have tested VIR at 60 plus years old that has been good for continued service. I would expect most domestic PVC cable to last a good 40 years. I believe manufacturers give a 25 year life expectancy on most cable.
The only really knackered cables I have seen have been VIR and some 40-50 year old PVC that had been running at or over it's CCC for decades.

 

[Marvo]

I'd say visual inspection especially at the accessories is equally important as testing but if insulation integrity is good then time is but an abstract.

 

[Dave OCD]

I'd say this was utter nonsense, have seen and tested hundreds of old T&E cables, often imperial sizes and 40+ years old and generally they are absolutely fine. Of course it depends on the environment, T&E installed outdoors will become very brittle within maybe 10 years and obviously continuous overloading will cause problems but all installations are different.

 

[Deleted member 9648]

When I had my last assessment (Stroma) the guy told me that if a house has cabling (so T&E) over 30 years old it needs ripping out and replacing, regardless. No IR tests, just replace. Bollox if you ask me. As far as I am aware 1) The actual copper never deteriorates, it is purely the insulation, 2) The condition of the insulation is totally dependant on the operating temperature over time and it can either be knackered or as good as new. The only way to tell is to test it?

I bet if the STROMA guy was told he needed to fork out a few grand to rewire his house which tested out perfectly fine he'd pretty soon change his tune. Always easy to spend other punters money.

 

[Lucien Nunes]

Don't forget this is a news article, which means any technical content is likely to be 50% random nonsense and misquotes. Of course actual insulation life depends crucially on temperature, load and the exact composition of the batch of material it was made from. You could probably take a reasonably educated guess at the useful remaining lifespan of the installation with the aid of a few chemical analyses of typical cable runs and a survey of operating conditions. The problem with taking an educated guess in a high profile situation such as this is that no-one can afford to be wrong. The surveyor will err on the side of caution, and the people he reports to will shave a bit off that to cover their own backs, etc. etc. Before you know it nobody is prepared to vouch for it lasting more than a few years, even where it's in AOK condition now.

 

[mattg4321]

As I thought too.

It'd certainly be an interesting job rewiring the houses of parliament though, and a very big one needless to say! Not sure I fancy it though.

 

[7029 dave]

That is bit of an sweeping statement, load of rubbish, visual inspection and testing is the only way, environment , temperature, conditions will determine the life span of any cable.

 

[davesparks]

As I thought too.

It'd certainly be an interesting job rewiring the houses of parliament though, and a very big one needless to say! Not sure I fancy it though.

Shouldn't be too hard, the whole place is wired in copper conduits with sweated brass fittings as far as I know so it should be a case of just pulling in some new singles

 

[mattg4321]

The actual work itself I'm sure I'd enjoy, it'd be all the hassle that goes with working in a place full of jobsworths maybe not.