EN 60204-1 (Safety of Machinery – Electrical Requirements of Machines) sets out both the required safety standards and the type and colour of cable that should be used for wiring an electrical enclosure. In addition, the International Electrical Commission has also issued a revised standard IEC. This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert symbol, notices referring only to property damage have no safety alert. Add green or green/yellow for ground and this is the vast majority of panels I've ever worked in. Analog signal wiring tends to be a variety of different colors depending on what cable was used to wire it up, but the stuff i install new usually has red, white, black, clear, and shield for a four. However, the NEC only specifies a few conductor insulation color codes. From UL508A, I assume this is the panel standard you're working to.
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