On 01/07/2020 09:57, wrote:
On 01/07/2020 08:33, wrote:
On Tuesday, 30 June 2020 22:27:52 UTC+1, Â* wrote:
I have a sub-main to a remote socket with a TT earth and, currently, the
SWA braid is terminated on a plastic enclosure. I need to change the
enclosure to metal so have to find a way to terminate the SWA braid
without connecting it to the metal enclosure.

Lateral thinking is use a

https://www.tlc-direct.co.uk/Products/WKSH506W.html

to join two lengths of SWA, but *not* use the armour continuity
straps. You therefore earth each section of SWA separately, from the
appropriate end.

There remains a risk of the separate earth potentials being exposed
during maintenance, so it should be appropriately labelled.

Owain

That's an interesting idea (I love lateral thinking) but I may have
come-up with a simpler one: find a regular nylon gland that will clamp
on the SWA outer (which may not be simple, I haven't looked yet) and
heatshrink the end of the SWA inside the enclosure to insulate the
braid. Perhaps adding a clamp on the outer, inside the enclosure, as
belt'n'braces.

Well, that was much easier than I thought. I had both a suitable nylon
gland and the heatshrink in "stock" - job now done but there's a
supplementary question about MCB ratings.
The 2.5mm2 buried SWA sub-main is currently protected by a B16 MCB at
the head end but I'd like to increase it to a B25 because I have a
couple of B16 RCBOs at the remote end. 25A is inside the rating of the
cable so I don't see a problem. Is there any reason not to do this?

BTW, everyone says put in a larger cable than you need when burying
cables - I wish I'd done that!