Electrical Labeling Requirements
We've all used them. Little books or rolls of numbers to label
conductors that help keep our circuits traceable. Labeled correctly,
both installations and troubleshooting are much easier.
Even rolls of colored tape serve as labeling. For example, when using large cables for high-amperage installations, all the power conductors usually have black insulation. So identifying a three-phase circuit can be done with color-coding. A 480-volt circuit is designated by brown, orange and yellow color-coding tape.