NEC Questions and Answers based on 2020 NEC^® - August 2021

Figure 01

For EC&M Magazine
By Mike Holt, NEC^® Consultant
Here's the follow-up to yesterday's newsletter. This includes the answers to the questions sent, so you can see how you did.

Note: The answers to these questions are based on the 2020 NEC.

Q1. What does the NEC require for short-circuit current rating of switchboards, switchgear or panelboards?
A1. Switchboards and panelboards must have a short-circuit current rating of not less than the available fault current. In other than one and two-family dwellings, the available fault current and the date the calculation was performed must be field marked on the enclosure at the point of supply. The marking must be of sufficient durability to withstand the environment involved in accordance with 110.21(B)(3) [408.6]. Figure 01

Q2. What is the Code rule that addresses side and rear access requirements to switchgear and panelboards?
A2. Connections. Each section of equipment that requires rear or side access to make field connections must be so marked by the manufacturer on the front of the equipment. Section openings requiring rear or side access must comply with the workspace and access to workspace requirements of 110.26 [408.18(C)].

Author’s Comment:
►The 2020 addition of this NEC section goes a long way to providing much safer access to the sides and the back of switchboards and switchgear where such access may be necessary to make wiring connections. This addition exemplifies the NFPA’s intent and continued efforts to reduce exposure and risk to unnecessary hazards to keep electrical workers safe.

Q3. What is the Code rule for the installation of panelboards in a face-up position?
A3. Panelboards are not permitted to be installed in the face-up position [408.43].

Author’s Comment:
►The 2020 Code Making Panel stated that this new limitation does not prohibit “mounting the panelboard in a horizontal face-down position.” However, 240.33 requires that enclosures for overcurrent devices be installed in the vertical position. If a panelboard is installed horizontally the overcurrent devices must have the “up” position be the “on” position [240.81].

Q4. What is the Code rule regarding reconditioning of luminaires?
A4. Luminaires, lampholders, and retrofit kits are not permitted to be reconditioned. If a retrofit kit is installed in a luminaire in accordance with the installation instructions, the retrofitted luminaire is not considered reconditioned [410.7].

Q5. A luminaire installed in a bathtub or shower area must meet what NEC requirements?
A5. A luminaire installed in a bathtub or shower area must meet all of the following requirements
[410.10(D)]:
(1) No part of chain-, cable-, or cord-suspended luminaires, track luminaires, or ceiling paddle fans can be located within 3 ft horizontally and 8 ft vertically from the top of the bathtub rim or shower stall threshold. 

(2) Luminaires located within the actual outside dimensions of a bathtub or shower to a height of 8 ft from the top of the bathtub rim or shower threshold must be marked for damp locations or marked suitable for wet locations. Where subject to shower spray, the luminaires must be marked suitable for wet locations. 

Author’s Comment:
►The previous Code language actually required that the luminaire be marked “wet locations where subject to shower spray.” There is no such marking on any luminaire.