"Andy Hall" wrote in message
...

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?

Could you mount an adaptable box close up to the CU housing (directly behind
it, say) and couple it mechanically with a long pattern conduit bush (would
probably need to be 25mm) and a few lockrings? Then take the SWA into the
adaptable box with a gland in the usual way, and feed the L&N thro' the bush
and into the CU itself.

It's not clear whether you're using the armour to provide an earth or
whether you need to isolate it at this end because the summer house will be
a TT system. If the latter, a plastic adaptable box may be preferable to
metal (since the armour should be considered as potentially live within the
separately earthed zone, IYSWIM).

--
Andy