Move Plug Socket

[johnson1]

I need to move a socket about 5 foot from its current location.

I have chiseled out to run a cable down and behind the skirting board. My question is joining the cables. I intend to use a 30amp porcelain block, leave this in the old socket housing and put a blanking plate on.
I have also noticed that I have 3 of each wire already twisted together, it’s a double socket with 2 sets of wires and I think it must bridge off through the wall to another socket in another room making a third set of wires.

Is this approach OK? What about that many wires into the one block?

 

[davelx]

You cannot run cables behind the skirting unless they are in earthed steel conduit or buried >50mm deep. Take a look at this:

//www.diynot.com/wiki/electrics:installation_techniques:walls

Even if you run the cables in a safe zone, if they are not in conduit or >50mm deep they will required RCD protection; if the ring final is already RCD protected that is taken care of.

From your description, there already appears to be a spur connected to this socket, so you cannot simply run a single cable from the existing position to the new position as that would mean you have two spurs from a single point on the ring.

You need to extend both legs of the ring to the new position. You can retain the connection to the spur behind the blanking plate. To do this you will need to identify which of the three cables is the spur.

Probably better to buy to modern plastic connector blocks, rather than use porcelain! Don't forget you will need G/Y sleeving for the CPCs.

And one further question - what room is this socket in?

 

[johnson1]

Its in the dining room.

I can see which one goes off through the wall but what about the other 2 sets of cables?? Surely they are both just live cables. Could I connect one set onto the spur and then the remaining set to spur off to the new soocket?

Are you saying porcelin blocks are a bad idea?

 

[chivers67]

You may as well use a fused connection unit to serve the other socket rather than a choc block, at least the cable will be protected by a 13amp fuse then (though you still need to listen to Davelx advice regarding mechanical protection) .

What does the spur currently serve? Is it a socket you use as if it isn't I tend to remove this.

Don't forget a grommet on the back box

 

[davelx]

No - the current carrying capacity of the cables in the ring a less than the rating of the protected device,; this is acceptable because there are two current paths to each socket on the ring and it it assumed that the loads will be distributed evenly around the ring.

A single one- or two-gang socket spur may be connected to each point on the ring - you are suggesting connecting two sockets to one point which the regultations to not permit, as this would violate the distributed load assumption to much.

Also DO NOT BREAK THE RING. If you do this then the cables in the ring are not sufficiently protected against overload and there is a risk of fire.

(Edit - >collision<)

 

[johnson1]

Ok, so are the two sets of cables the ring that is split by the socket???

And it already has another socket spured off of this going to another room. Are you saying that is wrong (not saying I have doen this its just how it is).

 

[ericmark]

The regulations treat ring mains in a special fashion and any other use of parallel conductors have very special rules. The basic is shown in an IET download

Ring Main

• ericmark
• 1 Jun 2009
• 6

IET Wiring regulation update

which shows all the possible combinations you are allowed. It does not show two spurs from a single point.
Also cable routes have to be vertical or horizontal not a mixture or diagonal. There is a safe zone at the top of a wall and corners but not bottom of a wall so to go down along and up to 450mm will not be permitted.
Yes I know it is done by many a DIY person who is not following regulations but you have asked if it is permitted what is the point of telling you the regulations if you are not going to use the information given?

 

[johnson1]

I do get the point and fully understand the zone (ignoring those for now, which I don't intend to ignore when actually do the work).

Attached is proposed (which I get the ipression is wrong)

From what I am getting proposed2 would that be right?

(ignore the dodgey drawings and the fact is not horizontal/vertical lines).

Untitled

• johnson1
• 1 Jun 2009
• 1

Untitled

• johnson1
• 1 Jun 2009
• 1

 

[Albert]

If the spur is just on the other side of the wall, I would extend the ring to the existing spur socket. The correct way to extend the cable would be by crimping. This will solve the issue of second spur on the same socket. All the advice given before is correct and I would add my advice to follow it.

 

[johnson1]

If I understand you correctly shoud it look something like proposal3 ??

Does it have to be crimps? Do they come with different ratings as you get with blocks?

Untitled

• johnson1
• 1 Jun 2009
• 2

 

[davelx]

No, that's an unfused spur with two sockets - not allowed. Have another look at the diagram in the post above. Proposal 2 complies with the regs but limits your total load on those two sockets to 13A.

You need a proper ratchet tool to use crimps safely and you can't put more than one wire in each end anyway. Nothing wrong with 30A terminal blocks (plastic) so long as they are accesible for inspections and tests (ie behind blanking plate).

 

[johnson1]

It kind of looks right (in the diagram they have two sockets, one in the ring the other spurred off).....
is the point at which I connect the ring main together, should the cables extend and meet at the socket on the opposite wall before spurring off back through the wall to the new socket??
see attached (that was a rubbish explanation).

I have looked at these crimps and can not find much on ratings, the best I found is use the Blue ones are they correct?

Untitled

• johnson1
• 1 Jun 2009
• 1

 

[davelx]

Yes, that last diagram is the preferred way.

Blue crimps for L+N (2.5mm^2 CSA), Red for the Earth wire (1.5mm^2 CSA)

http://www.tlc-direct.co.uk/Main_Index/Cable_Accessories_Index/Crimp_Lugs_and_Tools/index.html

http://www.tlc-direct.co.uk/Products/DVDHCR15.html

info on crimping:

//www.diynot.com/forums/viewtopic.php?p=478172#478172

EDIT: before someone else makes the point: the preferred way to do it is not to spur at all but to put all the sockets directly on the ring.

 

[johnson1]

Thanks everyone for the advice, bit long winded got there in the end.