| Andrew Gabriel 2007-04-11, 5:25 pm |
| In article <9C8Th.96$af3.67@newsfe1-win.ntli.net>,
"Paulmouk" <paulmo Rusty Car uk@ntlworld.com> writes:
> I've got some new three-core flex. 2.5mm squared.
>
> It's the sort of thing you would use for an extension lead except I've not
> seen any that thick before (cable is about the same diameter as my little
> finger).
>
> I can't see any reason why it shouldn't be used to extend my ring main but I've
> not seen it used for that purpose (possibly because it would be much more
> expensive than twin core and earth).
>
> Does anyone know of a reason why I shouldn't use it please?
There's no prohibition in the regs on using flex where solid core
cable would normally be used. The current rating is slightly less,
possibly due to less surface area, and there are no published
ratings for flex buried in walls, etc. which would make such
use questionable as you can't point to a table in the regs which
indicates it's OK. Published flex current ratings are for use
in free air or against one surface (and there are also published
ratings for multiple layers wound on a spool, not relevant here).
Another issue is making connections at terminals. Trying to
mix flexible and solid core conductor in the same terminal
invariably fails. Flexible conductors should have a bootlace
ferrule crimped or soldered on in this case. (Don't just
solder the strands into one solid piece without using a ferrule.)
Your 2.5mm˛ flex is worth much more than 2.5mm˛ T&E, so I
suggest you sell it on ebay and buy the right T&E cable,
which will be very much easier to use.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
|