Under this new Code Change you will be required to IDENTIFY the ungrounded conductors in a branch circuit when you have two different electrical systems in building. This is when you have 277/480 and 120/208. They instruct you to identify them by color coding, marking tape or some kind of other approved means. It states that you also have to post it by the panel. Most inspectors are going to require that the entire branch circuit comply with this requirement, you will have to ask about travelers and switch legs coming off a branch circuit.
This past week I was asked if just taping the conductors will be acceptable, and looking at the section size does not matter and taping even 14 gauge wire will be just fine. After all this is Article 210 for Branch Circuits.
(C) Identification of Ungrounded Conductors. Ungrounded
conductors shall be identified in accordance with
210.5(C)(1), (2), and (3).
(1) Application. Where the premises wiring system has
branch circuits supplied from more than one nominal voltage
system, each ungrounded conductor of a branch circuit
shall be identified by phase or line and system at all termination,
connection, and splice points.
(2) Means of Identification. The means of identification
shall be permitted to be by separate color coding, marking
tape, tagging, or other approved means.
(3) Posting of Identification Means. The method utilized
for conductors originating within each branch-circuit panelboard
or similar branch-circuit distribution equipment
shall be documented in a manner that is readily available or
shall be permanently posted at each branch-circuit panelboard
or similar branch-circuit distribution equipment.
Till next week be safe work safe
Jake