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	Subject - Color Coding of 3 phase motors wood111 When wiring from a motor starter controlled by a PLC to a 3 phase motor. I thought the industry standard is all three wires should be black. What is the correct code for this? Thanks Jeff JimmyDee I always use black but I think any color but green, white or gray is OK. Jim iwire There are industry standards for this kind of work they are not in the NEC and I am sorry but I can not point you in the right direction. Scott Vickrey They are usually black because this is the standard color of the wire. There may be a standard I have never heard of, this would not be surprising to me. I can tell you from experience that as the motor is changed over the years these wires will get swapped (sometimes at the starter and sometimes at the motor) for the sake of correct rotation without regard for what is "proper". I guess if this was my decision to make I would mark them with the appropriate color code(Black, Red, Blue or Brown, Orange, Yellow). While on the topic of color code I have to get the following off my chest. When I worked in Austin, Texas The low voltage color code was red, black, blue and for high voltage it was brown, yellow, purple. This could be confusing because everywhere else it's different. I know this is trivial, but I just want to hear someone else has a nonstandard color code. iwire We here in New England use: Brown Orange Yellow Gray 480/277 Black Red Blue White 208/120 We have a code amendment that requires us to use white under 250 volts to ground and gray above 250 volts to ground. We often use these colors for motors but it is not a great idea as you are likely to switch rotation at the contactor not the motor, black would make more sense. The Standards I was referring to tell you what colors to use for PLC inputs, outputs, AC, DC etc. They are voluntary standards. aussiesparky Guys Here's another convention for you to realy confuse things. Stranded cables in Oz Active [Hot?] Red, White, Blue [L1,L2,L3] Black is neutral and green with a yellow stripe is earth [ground], this applies on either 400v 3phase and 220v 1phase.