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Ed Sirett
 
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Default Terminating SWA at insulated consumer unit

Rick Hughes wrote:

"Andy Hall" wrote in message
...
I don't believe that this one has come up in quite this form before so
should be worth a thread.

I'm completing a summer house in the garden and adding the electricity
supply.

This is being run from the main CU via SWA and enters the building
inside next to the outer wall. There is an inner studded and clad
wall, which over most of the building is insulated, but in the area of
the electrical services will be kept mainly clear. Thus there is a
compartment formed by a partly fixed and partly removable panel with a
65mm gap to the outside wall.

My original plan was to bring the SWA up inside the cavity and through
to the front just below a CU fitted to the front panel, terminating
in a 20mm gland fitted to the CU.

However, the CU is an insulated MK type which has T&E shaped knockouts
around the edges and some rectangular knockouts on the back. There
are no round knockouts for glands and not really a suitable place to
drill for one.

I thought of simply bringing the SWA into the back of the CU, running
the red and black core cables to the incomer breaker. However, this
does not seem that mechanically satisfactory. I can clip the cable
as far as a point close to the entry through the back.

An alternative idea is to use a metal box with 20mm knockouts at both
ends. This would be fitted in the cavity (screwed down) and use a
gland to terminate the SWA cable with the conductors going into a 30A
terminal block. 6mm^2 T&E would continue from there into the CU.

Has anyone had to deal with a similar situation, and come up with a
neat solution?


Andy - I did the latter fixed a small galv box alongside the CU, terminated
the SWA as normal on the galv box - and run the cores direct through the
box (with suitable grommet) into the CU.



Apologies for the p[revious blank post.

I had much the same sort of problems when wired my store room.

I used plastic boxes both end and a short length of T&E.
The armouring was earthed using the tag in the house end box.
I used 3 core 2.5mm^2 SWA so the third core was used to export the
earth.
[This practice is probably wrong since I used the yellow core sleeved
with green&yellow for the earth. ]


--
Ed Sirett - Property maintainer and registered gas fitter.
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