Brown = Live (EU conformity) ? Black = neutral (old BS conformity) ? That leaves grey for earth, no know conformity to me.
Thank you for contacting Prysmian Group UK Technical Support. The requirement for 3-core colours in BS5467 is for three phase colours, Brown, Black and Grey, and this is in line with Table 7C in Appendix 7 of BS7671 (The Wiring Regulations).
When used for a single phase 230V supply, there is nothing laid down in the wiring regulations. It is therefore the responsibility of the system designer. However, we would point out that the guidance given by ECA and NICEIC states that the brown should be used as the live, the black should be marked and used as the earth and the grey should be marked as the neutral.
Answered by: Nikki - Prysmian
Date published: 2021-09-10