Electrical Wire Color Code Chart in PDF. If you live in the United States and your home was built after the 1940s (or your outdated wiring has since been updated), you can expect the electrical wires behind your walls to follow certain color standards.Specific colors identify each wire’s function in a circuit. AC Single Phase & Three Phase And DC Wire & Cable Color Codes. However, as per local practice, the standard wiring color codes may be divided in two main categories. The switch diagram below is for a … American electrical contractors and electricians must comply with the National Electrical Code (NEC) for the color coding of wires. US, AC:The US National Electrical Code only mandates white (or grey) for the neutral power conductor and bare copper, green, or green with yellow stripe for the protective ground.In principle any other colors except these may be used for the power conductors. They are: 1. US AC Wire Color Code; US DC Wire Color Code; US AC Wire Color Code. The wire colors for this category are: Below is a simple light switch wiring diagram if needed. What Each Wire Color Means for You. The wiring color codes which are followed by US based on local practice are divided again into two groups: a)120/208/240 Volt AC Power Wire Color Codes in US. Electrical engineers, contractors, traders, manufacturers and especially electricians around the world use different electrical wiring color codes for cable and wire installation and electricity distribution in industrial buildings or … These are typically used for power wires in “branch circuits”.NEC defines White or Grey color for neutral wire and green/ green with yellow stripe/ bare copper for ground wire. Wire Color Codes For USA Phase 1: Black Phase 2: Red Phase 3: Blue Neutral: White Ground wire is either a Green wire, a Bare Wire or a Green wire with Yellow Stripe. Any other colors except these may be used for other power lines.