Old wiring color question

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Will B

Member
Location
Fremont, CA
I am working in an old building where the electrical was installed in the early 60's. It is consistant that both the 480V and 120/208V wiring is Black, Red, Blue. What gives? I have only been in the trade for 11 years, but 480V has always been Brown, Orange, Yellow. Can any of you enlighten me? Thanks!
 
I am working in an old building where the electrical was installed in the early 60's. It is consistant that both the 480V and 120/208V wiring is Black, Red, Blue. What gives? I have only been in the trade for 11 years, but 480V has always been Brown, Orange, Yellow.

Was that legal in the 1960's? I don't have a codebook of that vintage. In the current code, the two voltage systems shouldn't be using the same colors (210.5(C) & 215.12(C)), but 277/480v can be any colors as long as they're not white/gray/green or something used by the 120/208 system. (You could use blue/purple/yellow for 120/208 and red/black/orange for 277/480 feeders & branch circuits as long as it's properly documented. IMHO it wouldn't be a good idea, would confuse too many people.)
 

kwired

Electron manager
Location
NE Nebraska
I don't know how long NEC has had system identification requirements, but color coding is not a requirement - it is just the most common method and the brown, orange, yellow and black, red, blue are the most popular schemes used. Neither is a NEC standard.

You can also identify conductors with tagging, colored tracers in the insulation, printed text tracers in the insulation, paint, marking tape, or just about anything imaginable.
 

LEO2854

Esteemed Member
Location
Ma
I am working in an old building where the electrical was installed in the early 60's. It is consistant that both the 480V and 120/208V wiring is Black, Red, Blue. What gives? I have only been in the trade for 11 years, but 480V has always been Brown, Orange, Yellow. Can any of you enlighten me? Thanks!
Regardless of the colors,always have a good meter handy to check the voltage,you don't want to leave it to others to tell you what the voltage is.

Around here it is common that Brown,orange and yellow,Is 480/277 Volts,And Black,Red and Blue is 120/208.Volts,But it is not required and is not always that way 100%of the time,,,,,Always Check the Voltage with your meter.:)
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Consulting Electrical Engineer - Photovoltaic Systems
Regardless of the colors,always have a good meter handy to check the voltage,you don't want to leave it to others to tell you what the voltage is.

Around here it is common that Brown,orange and yellow,Is 480/277 Volts,And Black,Red and Blue is 120/208.Volts,But it is not required and is not always that way 100%of the time,,,,,Always Check the Voltage with your meter.:)
And also as always, check the requirements of your AHJ.
 

Will B

Member
Location
Fremont, CA
Thanks for the replies. I should also mention that the wire has cloth covered insulation which is colored. There is no phase tape on the wire itself.
 
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