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Discuss Red-Yellow-Blue Color in the UK Electrical Forum area at ElectriciansForums.net
Red - Yellow - Blue is still extremely common phase colours in the UK. We may have gone over to Brown - Black - Grey but nearly everywhere I work is still RYB and still being fitted.
The US does care about colors. Up to # 8 you have to use brown, orange, yellow on 480vac 3 phase and any wire bigger than # 8 you are allowed to phase tape them. Let me ask you something, can you install 120vac and 277 vac in the same raceway exceptions includedIts not "standard" in the US. However, code does not care about wire color for the most part. As long as neutral is white or grey and the ground is green, green/yellow or bare then the NEC happy.
I say mostly because there are a few exceptions like isolated power systems in hospitals where they want brown and orange, ect.
Good to hear its still being fitted!
Black- that is interesting. I know in substation relay control wiring its often all grey with just number tags.
Bad idea if you ask me. Switzerland actually had it closer with Black, White, Red for phase and blue to neutral. I think way back when I think it was yellow with a red twirl. But all this is second hand information and research.
The AC unit in question is a US unit. And if it helps my schuko is 60Hz Go 60Hz!
The only way you can mix 120vac and 277vac in the same raceway is to use white for the 120vac neutral and gray with a tracer on it and the tracer can be any color except green for the 277vac neutral. Over time the gray will start losing its color and the you can’t tell which neutral is for your 120vac or 277vac. It’s not a good idea to mix voltages in the same raceway and if you do they all have to be the same insulationIn that regard yes- but what stops me from having Yellow-Purple-Pink-Gray on 120/208Y? Nothing that I know of.
277/480 and 120/208 can share the same conduit if the 120/208 conductors have insulation rated for at least 480 volts. Considering THHN/THWN is typically 600 volts rated you are ok.
Exceptions off the top of my head are life safety circuits- as they can not mix with normal power circuits- but that applies to all voltages. Same for service conductors and branch conductors but that still holds true for all voltages.
You also cannot use gray for a neutral for 120vacIn that regard yes- but what stops me from having Yellow-Purple-Pink-Gray on 120/208Y? Nothing that I know of.
277/480 and 120/208 can share the same conduit if the 120/208 conductors have insulation rated for at least 480 volts. Considering THHN/THWN is typically 600 volts rated you are ok.
Exceptions off the top of my head are life safety circuits- as they can not mix with normal power circuits- but that applies to all voltages. Same for service conductors and branch conductors but that still holds true for all voltages.
You cannot use natural gray for the neutral for 277vac mixed in a raceway with 120vac white neutralCorrect- though you can have solid gray.
What code section says you can not use gray as a neutral for 120 volts?
And therein lies the confusion.You cannot use natural gray for the neutral for 277vac mixed in a raceway with 120vac white neutral
Go to article 200.6(D) use and identification of grounded conductorsAnd therein lies the confusion.
Go to article 200.6(D) use and identification of grounded conductors
Yep, especially in the Maritime environment / Marine Engineering world.
I didn’t say grey was reserved for 277vac. I said you can’t mix 277 and 120 in the same raceway unless you use grey with a tracer of any color except green. Your last quote about brown orange yellow and you can’t use white for 277. You must not work in the electrical field because all you do is set there and quote Mike Holts books on a UK forum. If you know it all why don’t you have you license. If you and I doubt have a job doing electrical and if you did you would be a helperI read both 200.6 D and 200.7. Neither of which say grey must be reserved for a 277 volt system and white for a 120 volt system when in the same conduit/raceway/ect.
If I wanted to do Brown-Orange-Yellow-Grey for 120/208Y and Black-Red-Blue-White for 277/480Y I could legally do so.
NoI read both 200.6 D and 200.7. Neither of which say grey must be reserved for a 277 volt system and white for a 120 volt system when in the same conduit/raceway/ect.
If I wanted to do Brown-Orange-Yellow-Grey for 120/208Y and Black-Red-Blue-White for 277/480Y I could legally do so.
Why don’t you ask Mike Holts about 277vac with grey as neutral and 120vac with white as a neutral mixed in the same raceway and see what he saysI didn’t say grey was reserved for 277vac. I said you can’t mix 277 and 120 in the same raceway unless you use grey with a tracer of any color except green. Your last quote about brown orange yellow and you can’t use white for 277. You must not work in the electrical field because all you do is set there and quote Mike Holts books on a UK forum. If you know it all why don’t you have you license. If you and I doubt have a job doing electrical and if you did you would be a helper
Reply to Red-Yellow-Blue Color in the UK Electrical Forum area at ElectriciansForums.net