Standard Color Scheme for Wiring

I'm getting ready to solder some wires up to a connector for a GPS (EM-406A) and wasn't sure if there is a standard color I should use. I know for power and ground, I should use red and black, respectively. I'm only really looking to connect Tx and Rx on the GPS to my Arduino and wanted to know if there is some sort of standard convention to follow so I can stay consistent with whatever is out there. I borrowed a GPS from a friend and they just soldered haphazardly so ground is red, power is purple, Tx is green, Rx is brown, and so it's a mess and I have to think really hard to make sure I don't burn out the GPS. If there is a standard, it would be great to know. Thanks.

Aside from red for +V and black for Ground I don't know of any conventions that are generally followed. I think Twisted Pair cables (like Ethernet) have their color codes and USB cables have Green and White for the data pins. For serial connections you might try the convention used by the FTDI USB-to-Serial cables.

I like to use white or yellow for "signals", but AFAIK there are no general standards.


I like to use white or yellow for “signals”, but AFAIK there are no general standards.


I agree that there is no ‘official’ standard for DC circuits. At the refinery I worked at for decades they used 50 twisted pair black and white cables for most all their instrumentation junction box wiring runs, to and from the field/control house runs. Their standard? Black was positive and white was negative on all the 24vdc pairs. Why black for + ? because they wanted to follow the electricians standard for 120vac runs where black is the ‘hot’ wire and white the neutral wire. Go figure. :smiley:


For jumper wires I try to use YEL for clock, BLU for receive / data and GRN for transmit. This helps me with breadboards - particularly I2C and serial. For hard wired boards I usually use CAT5 wires - orange = VCC, brown = gnd and others similar to the jumpers just mentioned. Again no standard that I know of, but trying to be consistent might make troubleshooting easier. Whatever works best for you - usually a scheme that you can remember.

Thanks for the responses everyone. I'll come up with my own convention and go from there.