Wire color coding

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Is there a reference or standard that details standard color codes for wiring used inside a panel? I know green is always ground, white or light grey is neutral, black is 120VAC, but what about low voltages? What about 230VAC, 460VAC, etc? Does it matter if the signal is considered a switched voltage?
 
Welcome to the Forum. You are correct on your colors so far. No requirements on standard LV, usually installation or engineering requirements. I do not know about fire alarm and comm. requirements without checking. There are some "distinction" ruling for certain legs of 3-phase power, but no set requirement. Industry standards and suggestions usually apply.
 
There is more of an un-official standard , green and white are required though, The norm in my area would be BLK,RED,BLU as 120/240/208 and BRN,ORN,YLW as 480/277 other areas use differing colors for tagging voltages.
 
Color coding of control panel wiring is suggested in NFPA 79.

Line voltage - Black, regardless of phase or voltage
Control voltage, AC - red
Control voltage, DC - blue
Grounded conductor - white
Grounding conductor - green
Voltage from external source - yellow or orange
 
wbalsam1 said:
"Light" grey? Is this like "Natural" grey? :D
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No one makes 'natural gray' anymore. It's a throwback to the 'old days' of the trade. "Natural gray" was really a very light gray, and in poor light could easily be mistaken for white. Todays' gray is much darker than that.

So this brings up an important point: When you are working in an exisiting building, 'gray' could be either a grounded OR an ungrounded conductor. I've seen many cases where the 'gray' of today was deemed proper for use as a hot instead of a neutral because different interpratations of the meanings of 'gray' and 'natural gray'.

My codebook collection goes back to 1940, and 'natural gray' was considered a grounded conductor color back then. It was only in the 2002 that the reference to 'natural' was dropped from Art. 200.6, so there's a real potential today of running across a 'hot' gray wire!
 
tom baker said:
And IEC requires grounded DC to be white with a blue stripe.
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And it is not un-common for all of the other white conductors to have a colored stripe matching their ungrounded conductors especially for yellow/orange.
 
NJ DOT jobs use Blk/Red/Blue for 480v ...or some other combination NOT the typical B-O-Y combination.
 
as what other mention about the color code related to the voltage here,

my area typically

red,black,bleu, white - 208Y/120 system
black,red,orange,white = 240D/120 4 wire system

brown,orange,yellow, white or grey -480Y/277 v system
there is other one i heard this but it do used also in few spots
brown purple yellow .

but for other colorus it pretty much depending on the rest of the system and switching legs etc you may have to check it ahead of time some case each area is diffrent as well

Merci, Marc
 
jim dungar said:
And it is not un-common for all of the other white conductors to have a colored stripe matching their ungrounded conductors especially for yellow/orange.
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Where is a good source for these conductors?

I have had to get blue with white stripe and the shop took ages to get it.
 
iwire said:
Where is a good source for these conductors?

I have had to get blue with white stripe and the shop took ages to get it.
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our supply houses send it out to someone who stripes them but I haven't needed any in a long time so no good resource to pass on.
 
I am reminded of the old TV show WKRP ,in one show the electrician is removing wires from a control board ,Jonny Fever asks him " what are you doing" he replies " changing all these color coded wires to black" Jonny asks "why?" he replies " Job security"
 
frenchelectrican said:

there is other one i heard this but it do used also in few spots
brown purple yellow .
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This is all I use for 277/480. Orange could indicate to some a higher voltage to Gnd. as per 110.15.
 
Could be worse; you could work in Europe. They are just changing over their installation wire colour codes, which is all very boring, except for blue. In the old days, blue was one of the phase colours, now blue is neutral. Old colours are grandfathered, so no-one is forced to change anything, its just for new work or extending old work.

You can just imaging how many popped breakers and fried sparkies there is gonna be over the next 100 years before all the "old" blue has gone...
 
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