Firstly, the regulations merely state that conductors be
identified by the appropriate colours or alphanumeric.
Black and Brown should not be used for neutral!
Well, that refers to the identification markers, not the conductor insulation.
Non-harmonized colours did/does use black for neutral and there is plenty left. Do you sleeve these brown and blue?
Always use Blue or Grey sleeved blue for neutral.
Not quite - always sleeve neutral with blue.
That way people wont get confused between old and new neutral colours,
I don't get confused.
If sleeved correctly I will know - but still check; I wonder why.
If not sleeved, I simply don't know what the previous person has done; that is not confusion.
and end up thinking black in neutral when in fact it is a live conductor.
The same can be said for the grey.
Answer this:
A customer removes an extractor fan, cannot fit the new one, calls you.
You arrive,
A) find hole in wall with red/yellow/blue wires with no sleeving.
(Did anyone ever sleeve the blue with black?)
Do you connect red to L, yellow to SL and blue to N without checking?
If not, why not? After all, Live is red, Neutral is blue and SL must be yellow.
B) find hole in wall with brown/black/grey wires with no sleeving.
What's the difference?