Multiple tails from cut out ?

[rsmck]

We've recently bought a property which needs rewired - I'm not an electrician by trade but have a good understanding of electrics and am brushing up on the 17th edition - we intend to do much of the work ourselves partially as a cash-saving exercise but also for the experience (i've rewired part of a flat before, never a full house!)

Having not moved in yet I only have one small photo of the existing installation (attached) and i'm a little confused by the 4 tails that appear to come from the cut out where I'd normally only expect two.

It's also very hard to determine the earthing arrangement - TT seems likely but the earth conductor does disappear down the same hole at the supply cable comes from so I can't see where it goes from there (it could be connected to something for equipotential bonding)

Can anyone think of a reason there may be two sets of tails from the cut out ?

The intention is to rewire entirely and fit a 100A isolator after the meter to facilitate easier isolation in the future and a new 17th Edition compliant CU - all existing will be replaced as much of it is rubber rather than PVC and is degraded visibly in various places, especially the attic.

 

[malcolmsanford]

Though can not be 100% sure it seems that you may have an illigal tap off there. The 2 large cable go from the head to your meter and then to that distribution board and from there into the house.

The 2 smaller ones seem to go straight into that switch fuse and out in the small grey cable. Does that grey cable go to another meter perhaps an economy 7 off peak tariff? If not where does it go?

There is also a couple of labels one on the lid of the larger white box and the other next to the smaller one, what do they say.

As for the rest of your post all I can say is because of the Part P side of things it would be best for you to call an electrician and get them to sort things out. They will have the equipment and knowledge to help you out.

 

[mogga]

It could be a looped supply to flat upstairs

as for "doing most of the work yourself " as it will require notification through part"P" call an electrician who can part"P" things and advise you further
If you post your location there may be a forum member who can help near you

 

[sparks1234]

By the sounds of it the guy sounds fairly handy and knows a bit about electrics. If I were you I do the rewire myself and then get it signed off by the council.
There are a lot of people on here that will disagree but also a lot more that will help you out with knowledge if you post a thread here.
Dont forget though that you do need to inform them before you start work.
Good luck

 

[rsmck]

I'm not sure where they go, the house is still occupied by someone else so although i could take photos I can't remove anything yet to trace cables.

Can't be a loop to another flat (it's a semi-detached house), there is a garage (with power and it's own small CU) but I would expect (hope) that came off after the meter and not straight from the cut out! ... Much of this installation seems to date back to the construction of the house, so is over 50 years old in parts. The neighbouring property was recently rewired so I can't imagine they're fed from a loop from us.

The two thin cables go to that switch, which appears only to be connected to a central heating timer unit. (and yes, it's just a normal timer - not an Economy 7 system or anything like that)

Part P does not apply, this is in Scotland.

 

[telectrix]

I'm not sure where they go, the house is still occupied by someone else so although i could take photos I can't remove anything yet to trace cables.

Can't be a loop to another flat (it's a semi-detached house), there is a garage (with power and it's own small CU) but I would expect (hope) that came off after the meter and not straight from the cut out! ...

The two thin cables go to that switch, which appears only to be connected to a central heating timer unit.

Part P does not apply, this is in Scotland.

in that case, feel free to ask on here for any advice you need. however, if you are doing the work yourself, i would advise getting a qualified sparks to test and commission the job for you.

 

[rocker]

Yes mate regardless of Part P, what test equipment do you own? It's all well and good being a bit handy and knowing a thing or two, but how are you going to know what you have done is safe? Don't mean to be a party pooper mate but in saving a few quid you may end up burning the place down.

 

[telectrix]

Yes mate regardless of Part P, what test equipment do you own? It's all well and good being a bit handy and knowing a thing or two, but how are you going to know what you have done is safe? Don't mean to be a party pooper mate but in saving a few quid you may end up burning the place down.

i could always lend him my AVO 8

 

[Dunc]

Could be a supply to the adjoining property. I rewired a terraced house a few years back, pulled the main fuse to isolate the property to strip out the old CU to fit a temporary supply. A few minutes later got a knock on the door from the neighbour asking if the power was off. I gave the usual 'won't be me luv, the properties will be fed separately' reply only to realise on re-energising that the tails from next door came in to the out going side of my cut out. One call to Eon and someone was out to fix it the same day!

 

[rsmck]

Yes mate regardless of Part P, what test equipment do you own?

Fluke Multimeter, a Kewtech Earth Loop Impedance tester and a Megger PAT test machine but that one's not really relevant

Could be a supply to the adjoining property. I rewired a terraced house a few years back, pulled the main fuse to isolate the property to strip out the old CU to fit a temporary supply. A few minutes later got a knock on the door from the neighbour asking if the power was off. I gave the usual 'won't be me luv, the properties will be fed separately' reply only to realise on re-energising that the tails from next door came in to the out going side of my cut out. One call to Eon and someone was out to fix it the same day!

That's a worrying thought because both properties would then be sharing a single 100A supply fuse... will have a look around when I'm next in the property and see if I can see where the cables go, otherwise since this I'm basically treating this as a new installation I suppose it's relatively unimportant as I will simply be using one live from the supply, to the meter, to a new 100A isolator and to the CU.

When did it stop being accepted to wire adjoining properties in this way ? I presume if it turns out these cables do feed next door then Scottish Power will happily correct this at both properties without cost to the owner, as it's before the customers' equipment.

 

[mattmoo1974]

You could have a prefab weed growing room in your loft you know nothing about?

 

[Engineer54]

It's also very hard to determine the earthing arrangement - TT seems likely but the earth conductor does disappear down the same hole at the supply cable comes from so I can't see where it goes from there (it could be connected to something for equipotential bonding)View attachment 5449

It's not very hard at all to see/determine the earthing arrangement of your installation smack, ...It's clearly TN-S, as the main DNO earthing originates from the supply cable....

 

[rsmck]

There was some ambiguity when i looked at it - the connection apparently coming off of the supply cable that goes to the right of that shot (not the best photo I apologise) isn't connected to anything ! .. but yes I would expect is should be TN-S, the reason I wonder if it is TT is that there is an earth cable running from this CU down, through the basement, which disappears through a hole at the base of one of the internal walls which I believe may be connected to an earth rod. There are other houses in the same street (a family members') which is definitely TT...

I imagine the DNO will have a record of what it is, might give them a call and ask in the morning - also whether or not they have any history about it possibly having Economy 7 or something ... which would explain the second set of tails from the cut out.

 

[paturback]

There was some ambiguity when i looked at it - the connection apparently coming off of the supply cable that goes to the right of that shot (not the best photo I apologise) isn't connected to anything ! .. but yes I would expect is should be TN-S, the reason I wonder if it is TT is that there is an earth cable running from this CU down, through the basement, which disappears through a hole at the base of one of the internal walls which I believe may be connected to an earth rod. There are other houses in the same street (a family members') which is definitely TT...

I imagine the DNO will have a record of what it is, might give them a call and ask in the morning - also whether or not they have any history about it possibly having Economy 7 or something ... which would explain the second set of tails from the cut out.

Are you talking about the the long green and yellow cable running vertically or the silver/grey looking cable running horizontally bottom right corner of the pic?

As the silver/grey cable connected looks like its soldered would indicate TNS however if your saying this isnt connected to anything then it could be the supply has been converted to TT which obviously would have to be confirmed through further investigation,as would the two supply lines coming from the service head which are not connected to the meter.

 

[paturback]

oops did i say supply lines should it be tails.....