ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Wiring methods in U.K.

Scott,

So when did the NEC first actually specify that an EGC must be green? (If not bare.)

How did the general use of colors say 40-50 years ago differ from today? Was the BOY system in use for 277/480 (was the 277/480Y even in use then, or were these systems just 480 delta?).