In article ,
"G&M" writes:

White is often used for both 110v wires in sound and lighting touring
equipment to identify it as NOT one fo the three 240v phases or directly

Not to be confused with cream, which is a clean earth.

connected to it. Up to the 1970s white (line-ish) and black (neutral-ish)
were used.

Those are the US colours, except they're the wrong way round.

--
Andrew Gabriel