Whats your preferred wire colors?

[eight_bools]

Good Morning,

I am building a panel that has 120VAC, 24VDC, 12VDC, and 5VDC, and was wondering if anyone had any ideas for wire colors. I have black and white for the 120VAC, blue and blue/white for 24VDC, but I am not sure what to do for the 12 & 5 VDC.

I was thinking red and black for 12VDC, which leaves the 5VDC. Anyone have any ideas or advice based on what you have seen in the field.

The panel is for an alarm station controller with a PA system and a radio annunciator.


Thanks

 

[rQx]

Normally I say you would have same colors for all DC voltages

 

[Ken Moore]

Even if the panel is not UL, I still like to use the UL-508 color scheme.

 

[James Mcquade]

use a code standard. i am not familiar with UL regs, but i use the color code in NFPA 79 - industrial standard for industrial machinery.
since you build panels, ask what your customer wire color codes are for 3 phase.
james

 

[joseph_e2]

Definitely verify with the customer, but start with UL508 or NFPA 70 and 79.



In control cabinets here (well, how it's "supposed" to be):
Black wire = 240/480V 3-phase
Green wire = equipment ground
Red wire = 120V hot or switched conductors
White wire = 120V Neutral or grounded conductor
Blue wire = 24VDC system
Yellow wire = foreign power (wires that stay hot when the local disconnect is opened). Note: NFPA now specifies orange wire for this


I'd like to introduce:
Brown wire = 24VDC hot (maybe)
White with blue stripe = 0VDC


I've seen some bad mistakes in here, though. Like white wire for 120V hot/switched and black for whatever they needed it to be (120V hot/switched, 120V neutral, 24VDC, etc.).



We don't have many circuits that are <24VDC, but those few are all blue wire.

 

[geniusintraining]

I am all over the place but if I had a standard...

Black = 240/480
Black = I/0 wiring
Green = ground
Red = 120V positive
White = 120V neutral
Blue = 24V-
Brown = 24V+
Yellow = second power source

I reserve the right to change this as needed or if I run out of any color or if my customer is not to my standard

 

[Jim3846]

Black = 240/480 or
Yel/Brn/Org or Black = 3ph 480
red = 120vac I/0 wiring
brown = 24vdc I/O wiring
Green or green/yel = ground
Red = 120V positive
White = 120V neutral
Blue = 24V com
Brown = 24V+
Yellow or Orange = second power source

 

[Dale87]

Definitely verify with the customer, but start with UL508 or NFPA 70 and 79.



In control cabinets here (well, how it's "supposed" to be):
Black wire = 240/480V 3-phase
Green wire = equipment ground
Red wire = 120V hot or switched conductors
White wire = 120V Neutral or grounded conductor
Blue wire = 24VDC system
Yellow wire = foreign power (wires that stay hot when the local disconnect is opened). Note: NFPA now specifies orange wire for this


I'd like to introduce:
Brown wire = 24VDC hot (maybe)
White with blue stripe = 0VDC


I've seen some bad mistakes in here, though. Like white wire for 120V hot/switched and black for whatever they needed it to be (120V hot/switched, 120V neutral, 24VDC, etc.).



We don't have many circuits that are <24VDC, but those few are all blue wire.

We use same as above with exception to Grey for -VDC.

 

[Keystone]

Pretty close to some others:

Black = 240/480 or
Yel/Brn/Org or Black = 3ph 480
Red = 120 VAC
White = 120V neutral
Blue = 24 VDC Power & I/O wiring
Blue w/ white trace = 0 VDC (DC Common)
Green or green/yel = ground
Yellow = second power source (Yes it conflicts with 3 ph but only so many colors)
Purple = 24 VDC Safety wiring (Purple because that is the color left)
Purple w/ white trace = 0 VDC Safety wiring

Not saying it is perfect but at least we are getting consistent. It beats the euro panel I got that was all black 480V, 120V, 24V. I guess it cut down the confusion for the guy wiring.

 

[I_Automation]

Black is AC line voltage whether it's 120, 240, 480, or 575
Red = AC control voltage whether it's 120, 48 or 24AC (120 control voltage in a 120 line voltage machine means after a circuit breaker or fuse)
Blue = DC whether 24, 12, 5 or 48, and also DC motor power whether 90 or 180 unless purple below

White = AC neutral
Blue/White is sometimes used for DC 0V common, but usually just blue
Yellow is interconnects from other machines that could be any voltage AC or DC
Purple is used for DC motors if there are enough on the line
Green or Green/Yellow for grounds (except on Italian hoists where green is power for the motor brake and not to be touched [Yep!])


The thing I come across frequently is analog signal cables with black & white conductors. For most people black is hot and white is neutral, but in cars black is negative and I have seen quite a few machines where the analog is 0V-Black, +mA or +10V= white, and even that was screwed up on a new machine with a couple of signals reversed.


Plus you got the shop that hires a car porter from a Ford dealership into their maintenance department and lets him start wiring things (480 things) on his first day. Touch one machine and get shocked - the ground screw in the twistlock plug was black so it got a black wire and the green wire just connect to one of the 3 copper screws. Plus he could use whatever color wire he wanted wherever he wanted - like blue & white for 480 power

 

[parky]

Many years ago, I worked for a company who created commercial video game machines, these often were inported machines like space invaders glaxian among many others, we produced new games using existing hardware, one btch strait from Japan the wire colours if I remember correctly were white for neutral, green for live & red for earth (think that was the order but maybe the white & green were the other way round), you can guess what happened when our lads plugged them in. so no idea if it's still the same in Japan but RED was earth ?.