extra 2 gang plu socket off existing spur?

[millsy]

I'm really confused now!!

I traced back the spur in my attic to the bedroom below, when I took the face plate off there were 3 sets of cable in the socket, I presumed that it was 2 for the ring main plus the 3rd one as the spur to my attic.
I tested the circuit by removing the 3 live (red) wires from the socket and separated them, when I switched the power back on the rest of the sockets on my ring main still worked.

Does that mean that the bedroom socket is not within the ring main?

I tested another socket in another bedroom by removing the 2 live (red) wires , again when I turned the power on all sockets on the ring main worked?

Am It testing the ring main corectly?

 

[Andy-W]

I'm not an expert, but I think that after you disconnect one socket in a ring, you would expect the other sockets to still work when you switch the power back on. You have split the ring circuit into two radial circuits.

If however you disconnect two sockets, you would not expect the sockets between them to work.

Someone will hopefully correct me if I wrong...

 

[Carpman]

I'm really confused now!!

I traced back the spur in my attic to the bedroom below, when I took the face plate off there were 3 sets of cable in the socket, I presumed that it was 2 for the ring main plus the 3rd one as the spur to my attic.
I tested the circuit by removing the 3 live (red) wires from the socket and separated them, when I switched the power back on the rest of the sockets on my ring main still worked.

Does that mean that the bedroom socket is not within the ring main?

I tested another socket in another bedroom by removing the 2 live (red) wires , again when I turned the power on all sockets on the ring main worked?

Am It testing the ring main corectly?

The socket you have traced back to in the bedroom would be expected to have 3 T&E cables connected.(Two cables for the ring and one for the spur)

When you are separating the red wires and removing them from the circuit you are splitting the ring, if you energise the circuit with the red wires disconnected and seperated you would expect all other sockets on the ring to energise.

Same apply's for the other bedroom socket where you seperated and removed the red wire's.

You are not really testing the ring main that would require a low resistance ohmmeter.


hope this helps


Carpman

 

[securespark]

the double socket is fused at 2x13A = 26A.

NOOOOOOOO!

The double socket is not fused at all.

 

[skenk]

Aye thats right, nothing unusual there. You've probably actually found a reasonable way to check the integrity of the existing ring . . . You need to find which of the 3 sets of cable in the socket go upstairs to the attic. Then somewhere along the route of this cable put a FCU. Then reconnect the rest of the cable and existing socket to the load side of the FCU, and then wire up the new double to the existing one. . . then turn the circuit back on.

To be honest though yr not demonstrating much of a knowledge of electrics . . . .if yr going to take it on i'd advise you to be very careful, read up on erection methods (i believe the correct usage requires an 'ohh er missus' at this point!) and get it checked by someone who . . . well preferably an electrician.

Don't know what the legal implications are either? presumably it should have a minor works certificate dunno about notification . . .

Carpman - just keep carping on yeah!?

 

[skenk]

ss - the double socket itself is not fused but the point i'm making is, under the right (wrong) conditions, more than 26A can be drawn before anything trips/blows. I don't think anyone is disagreeing with that??

 

[ban-all-sheds]

Depends on the make of the socket - some might catch fire if you draw 26A from them....

 

[securespark]

Yes and this is just one of the anomalies of the regs that pro's take into account when installing.

I would only put a single socket on a spur to prevent abuse as much as possible.

In fact, I am more a fan of radials, as they are less easy to abuse/cock up.

 

[skenk]

bas - fair enough

ss - totally agree about only doing a single on an unfused spur, see earlier post.

'spose ideally radials are good but you'd need a few for yr typical house - WM, DW etc etc and with the price of copper . . .

Incidentally i've seen installations in France where EVERY outlet had it's own circuit you should see the CU . . . bonanza for the sparkies tho!

 

[Carpman]

Carpman - just keep carping on yeah!?

I'm going tomorrow for a few days cant wait

 

[millsy]

Skenk,

I was reading in a diy manual, about testing the ring, so I have misunderstood what the test was to produce.

I know which cable is the spur and I also know the other 2 cables are part of the ring, so I was planning to take a spur (via 30amp terminal junction box) from the curcuit (main ring) and run it upstairs to another 2 gang plug socket.

That should be OK shouldn't it.

 

[sparkyspike]

Yes