In article , David Looser
writes

BS7671 permits the use of other colours as long as the ends of the wires are
clearly labelled "L1", "L2" etc. I guess the installers simply didn't have
any grey cable.

No, this is an armoured underground cable with cores in the colours
stated.

L1 is brown, yet your picture has "negro" against L1, so I'm not sure that
we can place any confidence in its veracity.

shrug I took the photo, and have seen the installation several times.
Here's another photo, since you seem to have trouble handling the truth:

http://jasper.org.uk/disboard.jpg

Let's not talk about the croc clips, shall we? :-)

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