Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC) , Jim will help you solve it. Send questions to firstname.lastname@example.org. Answers are based on the 2020 NEC .
Pool house kitchen
My crew and I are wiring a pool house on a residential property. It has a full bathroom, storage area and an open portico with a permanently installed gas grill and a sink. There are three countertop receptacles. The inspector says we need to install two circuits. To me, this is overkill, and not required by the Code . Additionally, the pool house will be supplied by a separate service. Are we permitted to apply the 83 percent rule? While the pool house is not a dwelling unit, this is a residential installation.
The requirements for small appliance branch circuits in 210.11(C)(1) apply only to dwelling units. In order to be considered a dwelling unit, the pool house would need to provide complete and independent living facilities for one or more people, including permanent provisions for living, sleeping, cooking and sanitation. There are no such provisions in the pool house. The rules of 210.11(C)(1) for two small appliance branch circuits do not apply because the pool house is not a dwelling unit. Additionally, the permissive rules of Section 310.12 for reduced sizes of service and feeder conductors apply only to dwelling units and not accessory buildings.
The 2020 NEC now allows us to reidentify any conductor in a cable as an equipment grounding conductor (EGC). Can I do the same for the grounded/neutral conductor?
The revision you are referring to is in Section 250.119, which provides requirements for the identification of EGCs. The permission to reidentify an EGC in a muticonductor cable [250.119(B)] is not new. The previous requirement recognized only installations in which the conditions of maintenance and supervision ensured that only qualified people would service the installation. This qualifier has been deleted and the permission to reidentify an EGC may be applied in any installation. This section deals with EGCs only. There are significantly different requirements for grounded conductors. See Section 200.6 for permitted means to identify grounded conductors.
Are we permitted to install busway switches into an energized busway? We are having problems convincing an owner that we need to deenergize the busway to remove and add switches. The owner is telling us that NFPA 70E specifically permits working on busway while energized and that if manufacturers disagreed, that permission would not exist. Does the NEC address this issue?
The NEC contains minimum installation requirements for electrical safe work practices. This issue is not addressed in the NEC . The text referencing the task you describe is found in NFPA 70E, Table 130.5(C). This table helps the user identify the likelihood of the occurrence of an arc flash incident based on the task and equipment condition. This table does list insertion or removal of plug-in devices into or from busways as a task that comes with a likelihood of an arc flash incident. It is extremely important to note that the existence of this task in Table 130.5(C) of 70E does not in any way justify the insertion or removal of switches in an energized busway. The only reason this task is listed is due to the fact that the 70E committee understands that installers are interacting with energized busways in this manner. While I cannot speak for any manufacturer of a busway, I can tell you that they do not endorse or permit this activity. The National Electrical Manufacturers Association addresses this issue in NEMA Standards Publication BU 1.1-2010, the General Instructions for Handling, Installation, Operation, and Maintenance of Busway Rated 600 Volts or Less. In Section 7 of this document, there is a warning that severe personal injury or death may occur if installation activity, for example, insertion or removal of switches, is performed on an energized busway.
Sealants identified for the use?
During a recent inspection, our AHJ [authority having jurisdiction] asked me for documentation to justify our use of sealant around the conductors and nonmetallic conduit where the service conductors entered from below grade. I was caught off guard as we have always used this product without any issues. The inspector approved the installation but told me next time he will want me to provide some documentation. How do I do that?
Section 230.8 requires that where a service raceway enters a building or structure from an underground distribution system, it must be sealed. Additional text requires the sealants installed to be identified for use with the cable insulation, shield or other components. In order to be identified for the use, the sealant must be recognized as suitable for the specific purpose, function, use, environment or application. This can be done in many ways. Look at the product container. Some sealants are marked as suitable for use with all conductor insulations and all types of raceways, while others are limited to metal raceways. I suggest that you reference the product packaging and technical data available and document that for the AHJ.
Is a building used to store tractors, implements and tools on a farm considered an agricultural building?
No, Article 547 applies only to buildings where excessive dust and dust with water may accumulate, including but not limited to areas with poultry, livestock, etc., and where a corrosive atmosphere exists, including areas with animal excrement, corrosive particles and areas that are damp and wet due to periodic washing for cleaning and sanitizing with water and cleansing agents.
Single-pole separable connectors
When load testing generators, we use single-insulated conductors (commonly referred to as cam-lock) as permitted by the exception in 590.4(B) and (C) for tests. There is a new section in Article 406 that will affect the use of single-insulated conductors. I have never looked at these connectors as a receptacle, so what are they? The use of the terms “attachment plugs” and “connectors” are not very clear. I am also confused as to where the NEC applies. Does it always end at the receptacle?
Article 406 contains requirements for receptacles, cord connectors and attachment plugs (cord caps). The new section in Article 406 that you are referencing is 406.13 “Single-Pole Separable-Connector Type.” The parent text of this requirement clarifies that it applies to single-pole separable-connectors.
The NEC clarifies that these connectors are not receptacles. The NEC defines a receptacle, in general, as a contact device installed at the outlet for the connection of an attachment plug. A receptacle outlet is an outlet where one or more receptacles are installed.
This is a common discussion in the electrical industry and is compounded due to the fact that OSHA considers an extension cord as an extension of the branch circuit, and the female cord cap on the extension cord is considered by OSHA as a receptacle. The NEC defines an attachment plug, in general, as being a device inserted into a receptacle. We all understand that attachment plugs may be inserted into more than just a receptacle, including power strips and splitters. The NEC definitions are correct because the general rules of the Code apply to the installation ending at the receptacle. It is important to note that the NEC does include some requirements for equipment downstream of the receptacle including, but not limited to, appliances (422), extension cords [240.5(B)] and listed cord sets or devices incorporating listed GFCI protection for personnel identified for portable use [590.6(A)]. These requirements have existed since the 1993 NEC edition for theaters, etc., in Section 520.53(C). This new requirement applies generally where single-pole, separable connectors are used and will likely lead to revisions in Article 520.