Electrical 2 terraced properties being converted to 1

[NotAclueMe]

Looking for a bit of advice in whether this is practical, I have purchased the property next door and am in the process of converting the 2 terraced properties into 1.

Both properties have consumer units fitted and the wiring looks relatively new, I am thinking of adding a 100amp junction box to one meter and running a 16mm cable to supply the other consumer unit, the one being supplied will only be used for the lighting and ring circuit and all the other conections will be removed (cooker, shower etc)

Any advice greatly appreciated

 

[ricicle]

Anything is possible, but you will need an electrician on board from the off.

 

[bernardgreen]

Ensure the redundant meter and cut out are totally isolated from the CU they used to feed. It may be it is a different phase to the supply you are importing from next door. Take measures to ensure an accidental connection cannot happen.

The earthing arrangments in the two houses may be different and this may need to be changed.

Cancel the supply contract to end the standing charges etc applied to the redundant meter.

If the DNO are happy to leave the un-used cut out in place and powered then do so, if you ever decide to separate the properties to sell or rent one of them then having the cut out still there will save re-connection costs.

 

[ericmark]

My son did a large conversion of an old mill into a house and there was a worry over the supply to if 100A would be enough so he fitted a three phase fused isolator (160A) and fed three consumer units from that with 100A fuse fitted supplying each consumer unit. This mean it was easy to supply more than 100A single phase or to split to split phase or three phase.

This approach also means you can fuse down and use smaller cable or remove a single fuse to isolate one consumer unit.

I am not sure about the legal bit but would assume it would be considered as type tested he did not have any problem with LABC anyway.

There are of course many ways to do it. Because there was loads of work going on which required LABC the electrical work was just added to the list so the LABC charges were reasonable for the whole job. The problem with LABC was minimum charge with other work this is not a problem. But you do have to ensure you include electrical work on the application. They seem to expect electrical work to be done by a scheme member and unless your careful to include it often it's missed off.

Clearly you could use a scheme member in which case you need to ask him what he is prepared to do.

 

[JohnW2]

My son did a large conversion of an old mill into a house and there was a worry over the supply to if 100A would be enough so he fitted a three phase fused isolator (160A) and fed three consumer units from that with 100A fuse fitted supplying each consumer unit.

I'm a bit confused. If I understand you correctly, why have a 160A fuse (per phase) in series with a 100A fuse (per phase)? Also, was the supply really capable of 160A per phase - what rating were the cutout fuses?

Kind Regards, John

 

[NotAclueMe]

Ensure the redundant meter and cut out are totally isolated from the CU they used to feed. It may be it is a different phase to the supply you are importing from next door. Take measures to ensure an accidental connection cannot happen.

The earthing arrangments in the two houses may be different and this may need to be changed.

Cancel the supply contract to end the standing charges etc applied to the redundant meter.

If the DNO are happy to leave the un-used cut out in place and powered then do so, if you ever decide to separate the properties to sell or rent one of them then having the cut out still there will save re-connection costs.

Thanks bernardgreen was thinking of removing the fuse cartridge from the redundant meter to the CU and then putting the leads that went into the CU into a terminal box as another precaution.

do you think 16mm cable is okay, the run is approx 10 meters.

Thanks

 

[bernardgreen]

Do not touch the cut out. Not only is it "illegal" it can be very dangerous if the fuse holder falls apart. A not infrequent incident with older cut out. Hence the DNO and meter technicians wear ( should wear ) gloves and face shield when removing the fuse.

When you cancel the supply to the house ask them to arrange for the meter to be disconnected and they may arrange to remove the fuse.

 

[JohnW2]

When you cancel the supply to the house ask them to arrange for the meter to be disconnected and they may arrange to remove the fuse.

IIRC, asking for a supply to be disconnected usually automatically results in both meter and cutout fuse being removed, if not more.

Kind Regards, John

 

[NotAclueMe]

When you cancel the supply to the house ask them to arrange for the meter to be disconnected and they may arrange to remove the fuse.

IIRC, asking for a supply to be disconnected usually automatically results in both meter and cutout fuse being removed, if not more.

Kind Regards, John

Just took me 30 mins trying to find out what iirc meant, for anyone else as dumb as me it means "if I recall correctly"...

Thanks guys I think my first port of call is getting the meter removed.

 

[plugwash]

I'd say your first task is to get your electrician to put the new cable in. Probablly 16mm SWA cable backed up by a 60 or 80 amp fuse.

Then get the unwanted supply disconnected.

Then get your electrician to connect the new cable to the CU.

 

[JohnW2]

[Just took me 30 mins trying to find out what iirc meant, for anyone else as dumb as me it means "if I recall correctly"...

Sorry about that, but I don't understand how it took you so long. I just typed "IIRC" into Google and, within a second or two, virtually all the hits on the first page gave me the answer, in many cases without even having to click on the link! When you have some spare time, you might also try AFAIAA, AIUI, IMO, FWIW and a few other regularly occurring ones

Thanks guys I think my first port of call is getting the meter removed.

As others have said, it would be best to co-ordinate that with your electrician connecting the CU to the other supply (which will probably require having the main fuse removed from that supply).

Kind Regards, John

 

[ericmark]

My son did a large conversion of an old mill into a house and there was a worry over the supply to if 100A would be enough so he fitted a three phase fused isolator (160A) and fed three consumer units from that with 100A fuse fitted supplying each consumer unit.

I'm a bit confused. If I understand you correctly, why have a 160A fuse (per phase) in series with a 100A fuse (per phase)? Also, was the supply really capable of 160A per phase - what rating were the cutout fuses?

Kind Regards, John

Idea was still 100A supply to consumer units but up to 160A supply to house all phases in switched fuse box linked together. Or we could split phases if we were offered a split or three phase supply. We wanted the box rating at 160A not the fuses used inside the box.

A 100A supply was originally connected but we had the option. As it transpired the 100A was enough and the DNO's fuse never ruptured but we had no idea at building stage what the buyer would want. It was done so we could easy increase supply. The size of property was such that we wanted multi-consumer units anyway one consumer unit just for kitchen.

 

[JohnW2]

Idea was still 100A supply to consumer units but up to 160A supply to house all phases in switched fuse box linked together. Or we could split phases if we were offered a split or three phase supply. We wanted the box rating at 160A not the fuses used inside the box.

Maybe I'm being dim, because I'm still a bit confused, particularly by "all phases in a switched fuse box linked together". Are you perhaps saying that it was a single-phase 100A supply, but you wanted the option of easily changing to a 3-phase (3 x 100A) supply if you needed to? I still don't quite see why you wanted a 160A rated 'box' - did you even doubt that 3 x 100A would be enough?

Kind Regards, John

 

[NotAclueMe]

Thanks for all your help people its really appreciated.

As a thought or as an alternative would it be better if extended the cables from the ring and lighting circuits in the redundant CU and just connect them to the supplying CU in my property either in the existing RCD’s or add a couple more RCD’s
…
Seems this would be the least expensive route and probably look the best a there would only be the 1 consumer unit that way, could it be done or is there something I am missing…

 

[JohnW2]

As a thought or as an alternative would it be better if extended the cables from the ring and lighting circuits in the redundant CU and just connect them to the supplying CU in my property either in the existing RCD’s or add a couple more RCD’s ....
Seems this would be the least expensive route and probably look the best a there would only be the 1 consumer unit that way, could it be done or is there something I am missing…

In principle, that is certainly an option. What is practical/possible, and which is the better approach depends on lots of things - the number of circuits, the length of the circuits, the number of 'spaces' available in the CU etc - so this is definitely something you should discuss with your electrician.

Kind Regards, John