ELV cables

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Started a job today on a house that has been pretty much rewired - I'm finishing off the job (long story). Now all seems pretty much OK except that TV, Data, and Telephone cables have all been run loosely in same voids as LV cables.

So the question is how much notice of the 2" gap rule do other people take????

 

steptoe

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by LV do you really mean ELV? <50v ?

if so

I wouldnt worry too much,

bad harmonics at most,

more voltage down a satellite cable than down an ELV fan at any rate anyhow.!

may get oddities, but how difficult to change?

dont worry on the regs side, you will be covered there, ELV seperation covered,

 
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No, ELV is data, sat, etc. LV is 240v as in FTE as in normal domestic cables. Moving isnt a good option due to freshly plastered walls etc etc. Was thinking of claiming I had no knowledge of these and certifying accordingly as these were installed by previous spark. :eek: ?:| ]:)

However, as much as I know these types of cables should not be mixed (or separted by some form on insulation) I've never seen a problem caused by this, and about every house I've worked in has some form of this problem somewhere in the premises. So was wondering whether this was a case of over zealous regs or whether there is a genuine issue ?:| ? :| ?:| ? :|

 

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Me thinks that the reason for keeping them apart is not just harmonics, but the usual 'Fault Protection' ie if a fault develops on a say 230v cable which is then passed to either an ELV system or data system it could lead to serious doo doo.

Same old story of covering a certain part of the anatomy. :z

 

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Me thinks that the reason for keeping them apart is not just harmonics, but the usual 'Fault Protection' ie if a fault develops on a say 230v cable which is then passed to either an ELV system or data system it could lead to serious doo doo.Same old story of covering a certain part of the anatomy. :z
It's bad enough getting a belter off of a certain telephone wire when someone rings as you are terminating it, Apparently.

 

steptoe

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its all about the insulation being classed for the highest voltage present,

ie 230v AC,

the data cables etc will only be rated at 100v DC ish or so.

just sperate them as much as you can, not much else you can do really, ????

 
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its all about the insulation being classed for the highest voltage present, ie 230v AC,

the data cables etc will only be rated at 100v DC ish or so.

just sperate them as much as you can, not much else you can do really, ????
Exhuse my ignorence but how on earth may the sky cable become 'live' from the mains cables? Assuming protective devices operating ok then should only be for a fraction of a second IF it were to happen?

The reason must be due to interference?

 

steptoe

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Exhuse my ignorence but how on earth may the sky cable become 'live' from the mains cables? Assuming protective devices operating ok then should only be for a fraction of a second IF it were to happen?The reason must be due to interference?
inducted currents.

or if the insulation were to break down it would go live,

your protective device wont kick in/out untill the current leaks to earth,

by that time your sat box etc may be fried, or you too.!!

remember your sat cable already has 18v or so on it, your data and phone is also carrying some DC as well.

interference is an issue as well, esp so as not to cause a nuisance to other services, but thats not really a problem as regards the safety of the installation.

 
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I`ve known both sky & freeview boxes being fried, due to a signal line which twits with a t+e, and thereby induces a voltage. There`s sod all current behind it, but, as with ins. testing, the current isn`t the issue. So the protective device won`t operate. It is also possible for the induced voltage to sit on the chassis of a TV, by way of the coax plug. If you remove the plug from the set, it`ll bite you.

Had it, seen it, had to fault-find it.

Keep `em apart. Remember, YOU are the last spark there, according to the cert. Ignorance is not always a valid defence.

KME

 
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No. I`m sorry m8 - not clear enough......

The signal cables won`t have any noticeable effect on one another.

The power cables won`t have any effect on one another......

But the power cables should be routed apart from the sky/coax/scart cables.

HOWEVER.... The main issue here is the fixed wiring, in the walls (as far as regs are concerned.......)

OK now???

 
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No. I`m sorry m8 - not clear enough......The signal cables won`t have any noticeable effect on one another.

The power cables won`t have any effect on one another......

But the power cables should be routed apart from the sky/coax/scart cables.

HOWEVER.... The main issue here is the fixed wiring, in the walls (as far as regs are concerned.......)

OK now???
Perfect sense. Thanks mate. Beer? Guiness Drink

 

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