garage consumer unit supply advise swa 2 or 3 core

[Neil Gray]

Hi all

I'm installing an Garage consumer unit in an outbuilding being converted to a studio for a photographer just 1 ring main and lighting circuit.

supply cable 50M length SWA 10mm due to volt drop.  No room where Consumer unit is to bring SWA in and terminate so was going to put IP65 box on outside wall terminate cable in there then bring either the tails of the swa cable in flexible conduit to a box above CU then into CU.

I was going to use 3 core to make sure i had a good earth but then don't think ill have room to terminate the swa armouring and the 10mm earth cable  in the CU.

Did think of useing 10mm twin and earth from CU to IP65 box and connect to SWA cable but the the earth size and cable type are 2 different types.

could just use 2 core and use armouring as main earth then only 1 earth to connect into CU.

Advise please.

This could be used for An NAPPIT inspection so as to be right

[dpmiller]

hang on. This is possibly for a professional qualification and you're asking a question like this on a selfbuild forum?

[ProDave]

35 minutes ago, Neil Gray said:

I was going to use 3 core to make sure i had a good earth but then don't think ill have room to terminate the swa armouring and the 10mm earth cable  in the CU.

This bit worries me.  You do know how to terminate SWA, with a proper gland designed for the job that clamps the armour mechanically and makes contact to it.  You then take the earth connection from the "banjo" supplied with the gland.  It does not take up any room "in" the CU.

 

 

[Neil Gray]

HI thanks the reply

I cant connect an SWA gland to the side of the CU.  there's not enough room to physically do it.

I think ill just terminate in IP65 box on outside wall then bring tails of swa and earth from banjo in through wall in conduit to box above CU then go in behind CU is spaced off wall slightly as other cable go in behind.

 

[Temp]

So no room on any sides of the CU?

[ProDave]

Choose a CU with a gland knock out on the bottom.

 

Or just drill a 20mm hole.