Terminating SWA Cable

[Electron]

You can't supply a garage CU from a ring main. You will need to run a new cable back to the CU in the house and put it on it's own circuit.

I know that what exists is wrong and I do plan to correct them when I have finished my work on this project.

 

[Electron]

think he's saying there's an existing swa feeding a garage and that when the extension is getting built they may unearth it when doing the foundations , so he's going to install a new swa to the garage .
Think that's correct anyway .

That's correct. And I will take the new SWA back to the Consumer Unit, which should have need done in the first place.

 

[Electron]

Hum... he says he's isolated the supply, so presumably he hasn't isolated the socket circuit..... so the cable will be dead!

I have isolated the supply, which includes the socket circuit.

 

[Pete999]

What's a ring main doing in a house?

You're quite right Pete999. It's a Ring Final Circuit not a ring main. Thanks for pointing this out. Have you a solution to my question?

Is the SWA terminated in an adaptable box somewhere on the exterior of you house, this is usually the method when taking a supply from a Ring FC, as you say there is no evidence of any SWA at the CU.

 

[Richard Burns]

If the SWA is connected to the ring final circuit it would be best to disconnect it there rather than have a live cable running through a working area of underground works.
However if this is not possible then when you find the loose end of the SWA cable this end can be glanded with a CW gland into a weatherproof junction box and the cores terminated in connectors to prevent inadvertent contact. Because of the nature of the location you should be looking to find a strong junction box as well as waterproof.
Ensuring that the cable is secured out of the way of any proposed works would also be good.

 

[telectrix]

The Oxford dictionary is obviously out of date with regards to the current edition of the Wiring Regulations then.

no, it's correct. pete. a distribution circuit as a ring.

electrical supply serving a series of consumers

 

[Pete999]

no, it's correct. pete. a distribution circuit as a ring.

electrical supply serving a series of consumers

Yes I agree Tel but the OP was saying the OD was describing the RFC as a Ring Main, perhaps I should have read the ODs description first, RFC is a circuit supplying sockets a Ring Main is a distribution circuit, I knew that but was getting so peed off with folk calling the RFC ring main, perhaps I should stop being such a pedant.

 

[davesparks]

ring main - definition of ring main in English | Oxford Dictionaries - https://en.oxforddictionaries.com/definition/ring_main

Which supports Pete's point

 

[Midwest]

I have to say, when I was a young thruster, we called RFC's - Ring Mains. We also called lamps - light bulbs, dinner - tea and side cutters - snips. We also called socket outlets - plugs, with plugs called plug tops.

Thing was, no one got confused or the slightest bit annoyed. Well the elephant is in the room now, I've run the flag up the pole, lets see if anyone salutes it, perhaps its just my helicopter view of things

 

[Ian1981]

If you say ring main, everyone knows what you mean , like when people say bulb instead of lamp. People say Ze for tt when it should be Ra
Tamato tomato

 

[Electron]

If the SWA is connected to the ring final circuit it would be best to disconnect it there rather than have a live cable running through a working area of underground works.
However if this is not possible then when you find the loose end of the SWA cable this end can be glanded with a CW gland into a weatherproof junction box and the cores terminated in connectors to prevent inadvertent contact. Because of the nature of the location you should be looking to find a strong junction box as well as waterproof.
Ensuring that the cable is secured out of the way of any proposed works would also be good.

Thanks Richard for your advice. I'll terminate in an IP65 Junction Box ( IP65 Adaptable Box 80 x 80 x 52mm - http://www.screwfix.com/p/ip65-adaptable-box-80-x-80-x-52mm/14556) and secure this in a safe location until I can fit a new Consumer Unit and replace the cable to the garage CU with a new SWA cable between them.

 

[Toneyz]

I assume that you know which circuit in your consumer unit.Safely isolate this circuit and look behind the socket outlets if it has been spurred off one of these. You may find this as one of the sockets has three cables rather than two.

 

[Octopus]

^^ still think this is a poor solution. NOTHING stays water proof for ever.

Can't you locate the cable, then bring it "out" of the ground and terminate it in an ip rated socket that could then be used?

Edit: I was fault finding a socket circuit today, which included the shed .... The swa was connected to a socket on a wall backing onto the garden. Neither end of the swa was terminated properly, and despite a dual RCD board being in place, all the sockets were on the same RCD.......so when it trips, all but the lights go out.

 

[Toneyz]

^^ still think this is a poor solution. NOTHING stays water proof for ever.

Can't you locate the cable, then bring it "out" of the ground and terminate it in an ip rated socket that could then be used?

Good solution to the problem as long as RCD protected.

 

[Octopus]

Good solution to the problem as long as RCD protected.

If not, fit an ip rated RCD socket.....