Stephen wrote:

I wonder if you can help me? I have a socket that is halfway up the
wall and I would like to lower it to a more sensible level. The wires
to this socket are run in the metal capping you describe. I am
concerned because both wires are run together and having read the
above post it sounds as though the cables are rated at 19.5A "below
what is necessary for a ring".

Not sure that is correct anyway...

From the on site guide - 16th edition:

"7.2.1 Grouping of Cables
(i) In domestic premises, except for heating cables, the Table 4B1
conventional circuit design permits any number of
single-layer circuits when the spacing between
adjacent surfaces of the cables exceeds one cable
diameter, and, for other than semi-enclosed fuses,
(BS 3036) up to 5 touching, single-layer, circuits, when
clipped to a non-metallic surface (Installation Method 1)"

also, metal capping buried in plaster is treated as reference method C
in the 17th edition (i.e. clipped direct - as above). Hence the
installation method has no addition de-rating to impart.

In fact there are a couple of notes in the 17th edition that also
mention that mechanical protection over a cable buried in plaster (i.e.
capping) may in fact increase it current carrying capacity (for cables
with conductors of CSA = 16mm^2)

So, in summary, nothing to worry about.


--
Cheers,

John.

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