Phase wiring in single cores

[Sparks1974]

When wiring in conduit and trunking in single core cables from a three phase board do you use the three phase colours, Brown, Black & grey or do you only use brown for all three phases?

 

[littlespark]

Either.

If using only brown for each phase, identify the ends with sleeving or tape for L1, L2, L3

 

[James]

Depends.
If it is to supply a multi phase device or socket, the phases should be identified at both ends.
Easy way to do this is coloured wires.

If you are going out to different single phase devices fed from different phases, brown would be my preferred choice for all 3 phases.

 

[Rockingit]

If you're running a 5c feed then a roll of black and grey single cost the same as brown, so it's a no-brainer.

Where using brown as purely the only colour in a 3ph distribution to 1ph outlet scenario can get muddled is simply in cable management and identification back at the feeder board - in which case your best friend isn't colour it's L1, L2 & L3 labelling on the brown conductor. That way, you've got the convention of brown and blue at the 1ph outlet (and in a large commercial setting one would hope the outlet itself would have a supply label on it anyway) and a clearer picture back at the board/s.