Adam wrote:

Reg 514.4.2

The bi-colour combination green-and-yellow shall be used exclusively for
the identification of a protective conductor and this combination shall
not be used for any other purpose"

I would suggest that this regulation specifically refers to the visible
green/yellow colour combination of the conductor. If the visible colours of
a conductor are green/yellow, then that 'exclusively identifies that
conductor as a protective conductor'.

However, if the exposed green/yellow conductor of a multicore cable is fully
oversheathed or sleeved in another colour (e.g. brown) at the terminations,
then IMO, the new designation for that conductor would not contravene the
regulations.

It's not that different from oversheathing the blue neutral in a switch drop
with brown sleeving to redesignate it as a live conductor.
--
Interloper