The mandatory colors for power wiring in the National Electrical Code (NEC) are Green, Bare, or Green/Yellow (a yellow stripe or band on green) for the protective ground (PG), and White (or alternatively Gray) for the neutral wire. Colour identification by using common colours is permitted, provided that there is no risk of confusion and no GREEN or YELLOW is used, except in the two-colour combination GREEN-YELLOW. When using color codes for the identification of current conductors, it is recommended to use the following. Wiring color codes vary by region and are designed to meet local standards and regulations for AC (Alternating Current) single-phase, AC three-phase, and DC (Direct Current) systems. By using standard or custom color codes, technicians can install, inspect, and repair systems quickly and reliably. Customers occasionally inquire about the use of wire color versus other identification methods.
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