As written in 110.16, which of the following items is not required to be field marked to warn qualified personnel of potential electric arc flash hazards?

  1. A NEMA 3R-rated disconnect switch readily accessible to an air conditioner condensing unit installed outdoors.
  2. Electrical equipment such as a generator transfer switch.
  3. A panelboard.
  4. A switchboard.

Answer: A

As noted in Sec. 110.16, electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers, and meter socket enclosures require a field-installed warning label (i.e., label). Because the disconnecting means readily accessible to the air conditioning equipment is not examined, adjusted, serviced, or maintained while energized, it would not require the warning marking in this example. Would it be a good practice to mark this disconnect (label)? I think so; however, it’s not required by the Code.

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at necexpert@aol.com.