Yet another garage power question. Sincere apologies.

[100% useless]

I know this has been done to death many times over and you are all probably sick of it by now, but unless I say exactly what I intend doing and someone says yes that is safe I wont have the confidence to continue.
I would like to run some power to my garage, 8 metres from the house, by the simplest possible method, to run 2 or 3 triple sockets and lighting. Sockets are for small tool use only and no more than one will be in use at any given time. The amount of sockets is for convenience only.
As there is no spare fuse on the board I was thinking of breaking into the ring in the kitchen by way of a juntion box running to 13amp RCD FCU. This would be connected to 3 core 2.5mm SWA which I can feed through an air vent approx 1/2 metre above the ground. SWA would then be buried until it reaches the garage where it would be fed through the wall directly into a 20amp DP metal box. From then on into sockets on a radial(?) and a 3 amp FCU for lighting.
Sorry for being so long winded but thought it best ot give all facts as I know. Is it safe or would it be worth getting the wife to try it first and also would I earth SWA cable at metal box end using armour.
Thank you

 

[Deleted member 26818]

I wouldn't use an RCD FCU at the house end, neither would I use 3 core SWA.
Place the RCD in the shed, use 2core SWA with the armour as the CPC.

 

[100% useless]

Thank you for your response. You obviously know a great deal more about it than I do so may I ask why the RCD in the shed?

 

[telectrix]

agree with spinlondon here, but at the point where you take off from the ring, i would fit a DP isolator and 16A MCB or fuse, gives you an extra frew amps over a FCU.

 

[telectrix]

if your ring is RCD protected anyway, you don't need RCD in the shed.however, doing it this way could lead to shed faults tripping out the house RCD, which is not ideal.

 

[100% useless]

No Ring is not RCD Protected. Noah refused to have it in the ark as it was too old.

 

[Deleted member 26818]

The main reson I would have the RCD in the shed instead of the house, is inconvenience.
To my mind, if the RCD trips, it would be easier to re-set in the shed, rather than have to go to the house.
Technically you should not have the power and the lights on the same RCD, in fact there is no requirement to have the lights on an RCD at all.
Then there's cost.
I would imagine that an RCD FCU and a DP switch will work out slightly more expensive than just a plain FCU and an RCD instead of the DP switch.
There's no requirement for the SWA to be RCD protected, as it's not concealled in a wall, and in any case has an earthed metallic sheath.

 

[100% useless]

That was my first post and what a painless and informative event it tuned out to be. Can't believe I was actually nervous about asking. Anyway thanks to spinlondon and telectrix I am now settled on how to proceed and off to Screwfix for bits. (still think I'll get to missus to try it first)
Thanks again