So what do you do......

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Todays job "fit some new lights in the bathroom"

Before I got to the job they had already re plasterboarded the ceiling of the bathroom.

So I go into the loft, expecting to find the old light fitting there or something to join onto.

What I found was SIX 1mm twin and earth cables chopped off, some with the ends taped up, some just chopped off.

And the old 6mm feed to the shower, and a 2.5mm T&E and a 3 core t&e

After some investigating and testing, I determined none were live, but some still had neutral and earth connected. None were the feed for the lighting circuit.

I disconnected the old shower feed at the CU.

Eventually I found the old bathroom ceiling rose moved some distance away and buried under loft insulation.

So I've fitted the lights, blocked off all the unknown cables and as I say, disconnected the old shower feed.

I've advised the customer that I should spend some time investigating and removing all these old cables, particularly the ones that still have neutral and earth connected somewhere, but customer is not interested in paying me to do that.

I guess there's nothing you can do. Issue a danger notice perhaps? (though with none actually being live is it really dangerous?)

If I'd had a camera, the sight that greeted me in the loft would be in the black museum forum.

 
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IMHO all cores of unused cables should be correctly terminated and preferably tied down to a reliable earth, that obviously gives an issue as you have N's & E's, so if you have RCD's happy days!...

Remember that N is a live conductor so it must never be left "bare" as it were.

 
The thing is how do you know that those cables will remain dead,,, they could become live with the flick of a switch!.... Possibly?

How many houses have cables like these in them? Loads,,,, maybe the other end is disconnected as well??

Make a note of what you've found inc. myour recommendations on your invoice

 
what I do if I disconnect a cable, and am unable to remove said cable, for whatever reason, is to leave the earth connected at the consumer unit, then create a short(in any suitable manner) across all three conductors at the 'loft' end,

that way re-energisation of the cable is not normally possible without someone first determining and sorting out the cable,

does that make sense?

---------- Post Auto-Merged at 21:12 ---------- Previous post was made at 21:11 ----------

EDIT,

Dave, you can only do what you are paid and asked to do,

 
This reminds me of a call out the other night which was RCBO tripping out now and then which happened after a shed was taken down. This was because fuse had been taken out of RCD spur but as it was a latching one the neutral was still connected and was going down to earth when it rained. Shame sombody didn't disconnect that correctly and not just take fuse out. I always try to remove unused cables but sometimes its just not practical as long as they are not bare and safely taped up shouldn't really be a problem although if they are outside they really need disconnecting properly.

 
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what I do if I disconnect a cable, and am unable to remove said cable, for whatever reason, is to leave the earth connected at the consumer unit, then create a short(in any suitable manner) across all three conductors at the 'loft' end,that way re-energisation of the cable is not normally possible without someone first determining and sorting out the cable,

does that make sense?

---------- Post Auto-Merged at 21:12 ---------- Previous post was made at 21:11 ----------

EDIT,

Dave, you can only do what you are paid and asked to do,
Any dead cables I cannot fully remove ALWAYS have the L-N & E stripped back and twisted together, so anyone metering out the other end will see a direct short.. and/or it will trip RCD, blow fuse if accidentally energised.

 
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Any dead cables I cannot fully remove ALWAYS have the L-N & E stripped back and twisted together, so anyone metering out the other end will se a direct short.. and/or it will trip RCD, blow fuse if accidentally energised.
exactly.

 
Also..

if you happen to find two cables cut off in a loft or under a floor ..

or wherever...

If one is just CUT

and the other is 3 x bare conductors stripped and twisted it is much easier to suss out which one is dead than the other!!!

:Salute

 
How serious I`d consider it would, to a certain extent, depend on the earthing system; though I agree completely with the guys above.

Much more of an issue with TT, IMO - and the problem is that twisting all the cores together will trip the RCD. Customer isn`t going to pay for their shiny new whatever, if you`ve effectively isolated their install by putting a N-E short in place!

And if there ISN`T an RCD, and a neutral fault occurs - you`ve helped to transfer that potential to earth.......

 
Sounds like I need to go back and short all the L and N cores on the unused cables.

Then later on, if someone turns on a mystery switch somewhere and a trip blows, I'll get called back to investigate the fault.

I might actually be going back to fit an outside light, if so that will involve a trip into the loft, so ideal opportunity to do that.

 
Well i have learnt sommit today......

in future i will twist them together put them in a jb and label unknown.

do you guys leave a note in the cu /???????

what i normally did was put them in a jb if i couldnt trace them andleave a note..

 
Any dead cables I cannot fully remove ALWAYS have the L-N & E stripped back and twisted together, so anyone metering out the other end will see a direct short.. and/or it will trip RCD, blow fuse if accidentally energised.
I do some work occasionally with the lads that do the 11KV subs. On the last 2 jobs they ran some spare 'tails' from the sub, out through the base concrete and left them outside for future connection. They had a little packet of bits...this was a piece of braided tape, some plasterboard nails and a heat shrink cap. They laid the braid over the end of the single core solid Ali cable, nailed it into the end and into the Cu earthing outer, then folded it over and did it again. Fitted heat shrink cap and buried it. Same priciple, if it gets energised by mistake then it goes pop and lifts the fuse/protection... :coat

 

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