In the U.S. a few days ago, the ground wire is green, yellow-green stripe or bare wire, the neutral wire should be white or gray, and the circuit wire may be black, red, blue, yellow, orange or yellow. The specific color depends on the voltage.
These color standards are for the United States, and other country codes are different (Canada is very similar to the United States). For example, Australia, New Zealand and the United States have the same ground wire color, and their neutral wire is blue or black. Moreover, the live wire can be any color other than the ground wire and the neutral wire. Red and brown are recommended colors for single-phase wires, and red, white, and blue are recommended colors for multi-phase current charged wires.
The UK has recently (2004) changed its system to comply with the International Electrotechnical Commission (EC). Their ground wire color (yellow-green stripes) remained unchanged, and the neutral wire color changed from black to blue. Similarly, the single-phase wire used to be red but turned brown. In addition, the marking and coloring of polyphase lines in the UK have also changed: L1 changed from red to brown, L2 changed from yellow to black, and L3 changed from blue to gray.
