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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.
Figure 01
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Figure 01
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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.
Underlined text indicates a change for the 2020 NEC.
Q1. What are the NEC requirements for GFCI protection of branch circuit receptacles in dwelling units?
A1. 210.8 GFCI Protection
Ground-fault circuit interruption protection, located in a readily accessible location, must be provided in accordance with 210.8(A) through (F).
Author's Comment:
►According to Article 100, a Ground-Fault Circuit Interrupter (GFCI) is a device intended to protect people by de-energizing a circuit when a current imbalance has a value of 6 mA or higher and does not trip when the current to ground is less than 4 mA.
Author's Comment:
►The GFCI circuit breaker provides ground-fault protection starting at the breaker, so the entire circuit has ground-fault protection. A GFCI receptacle provides ground-fault protection for whatever is plugged into it, but also has load-side terminals that provide downstream protection for any other receptacle(s) or device(s) on the circuit.
►According to Article 100, Readily Accessible means capable of being reached quickly without having to climb over or remove obstacles, or resort to the use of portable ladders.
Informational Note 2: See 422.5 for GFCI requirements for specific equipment such as automotive vacuum machines, drinking water coolers, high‘pressure spray washing machines, tire inflation machines provided for public use, and vending machines.
Informational Note 3: See 555.9 for GFCI requirements for boat hoists.
Informational Note 4: Additional GFCI requirements for specific circuits and equipment are contained in Chapters 4, 5, and 6.
For the application of 210.8(A)(7), 210.8(A)(9), 210.8(B)(5), and 210.8(B)(12), the distance is measured as the shortest path an appliance's supply cord will follow without piercing a floor, wall, ceiling, fixed barrier, or passing through a window.
Author's Comment:
►This new language literally serves to require a receptacle in an adjacent room and to have GFCI protection where that receptacle is within 6 ft of a sink. This would be the case in a house with a master suite and a bedroom receptacle outside of the bathroom doorway, but within 6 ft of the sink in the master bath.
(A) Dwelling Units. 125V through 250V receptacles installed in the following dwelling unit locations must be GFCI protected.
Author's Comment:
►Note that this expansion applies no matter the ampere rating of the receptacle. It is no longer limited to just 15A and 20A receptacles as it was in the previous edition of the NEC.
(1) Bathroom Area. GFCI protection is required for all receptacles located in dwelling unit bathroom areas.‚
Author's Comment:
►According to Article 100, a Bathroom Area is an area that includes a basin as well as one or more of the following: a toilet, urinal, tub, shower, bidet, or similar plumbing fixture.
(2) Garages and Accessory Buildings. GFCI protection is required for all receptacles located in garages of dwelling units and grade‘level portions of accessory buildings used for storage or work areas of a dwelling unit.
(3) Outdoors. GFCI protection is required for all receptacles located outdoors of dwelling units, including receptacles under the eaves of roofs.
Ex: GFCI protection is not required for a receptacle dedicated to fixed electric snow‘melting, deicing, or pipeline and vessel heating equipment if the receptacle is not readily accessible and the equipment has internal ground‘fault protection of equipment (GFPE) [426.28 and 427.22].
(4) Crawl Spaces. GFCI protection is required for all receptacles located in dwelling unit crawl spaces at or below grade.
(5) Basements. GFCI protection is required for all receptacles located in finished and unfinished areas of a dwelling unit basement.
Ex: A receptacle supplying only a permanently installed fire alarm or burglar alarm system is not required to have ground-fault circuit-interrupter protection.
(6) Kitchen Countertop. GFCI protection is required for all receptacles that serve kitchen countertop surfaces.
Author's Comment:
►Receptacles located below a countertop for appliances, such as trash compactors or garbage disposals, do not require GFCI protection unless they are located 6 ft or less from the top inside edge of the bowl of the sink [210.8(A)(7)].
►A refrigerator is not a countertop appliance so GFCI protection is not required, unless the receptacle is located 6 ft or less from the top inside edge of the bowl of the kitchen sink [210.8(A)(7)]. Figure 01
Author's Comment:
►Outlets supplying dishwashers require GFCI protection [210.8(D), 422.5(A)(7)].
(7) Sinks. GFCI protection is required for all receptacles located within 6 ft from the top inside edge of the bowl of a dwelling unit sink.
(8) Boathouses. GFCI protection is required for all receptacles located in a dwelling unit boathouse.‚
Author's Comment:
►The Code does not require a receptacle to be installed in a boathouse, but if any are installed, they must be GFCI protected.
(9) Bathtubs or Shower Stalls. GFCI protection is required for receptacles located within 6 ft of the outside edge of a bathtub or shower stall not installed within a bathroom as defined in Article 100.
(10) Laundry Areas. GFCI protection is required for all receptacles installed in the laundry area of a dwelling unit.
(11) Damp and Wet Locations Indoors. GFCI protection is required for all receptacles installed in indoor damp and wet locations.
Q2. What are the NEC requirements for GFCI protection for branch circuit receptacles in locations other than dwelling units?
A2. Other Than Dwellings. GFCI protection is required for all 125V through 250V receptacles supplied by single-phase branch circuits rated 150 volts or less to ground, 50A or less, and all receptacles supplied by three-phase branch circuits rated 150 volts or less to ground, 100A or less, installed in the following locations [210.8(B)].
(1) Bathroom Areas. GFCI protection is required for all receptacles located in bathroom areas.
Author's Comment:
►According to Article 100, a Bathroom Area is an area that includes a basin as well as one or more of the following: a toilet, urinal, tub, shower, bidet, or similar plumbing fixture.
(2) Kitchens. GFCI protection is required for all receptacles located in kitchens or areas with a sink and permanent provisions for either food preparation or cooking.
Author's Comment:
►The NEC does not give clear guidance, but since list item 210.8(B)(5) already covers receptacles within 6 ft of the sink, this rule serves to cover receptacles beyond that distance but still within the area containing a sink and provisions for food preparation or cooking.
(3) Rooftops. GFCI protection is required for all receptacles located on rooftops.
Author's Comment:
►A 15A or 20A, 125V receptacle outlet must be installed within 25 ft of heating, air‘conditioning, and refrigeration equipment [210.63].
►Roof top GFCI receptacles are only required to be readily accessible from the rooftop itself. [210.8(B)(3) Ex.]
(4) Outdoors. GFCI protection is required for all receptacles located outdoors.
(5) Sinks. GFCI protection is required for all receptacles located within 6 ft from the top inside edge of the bowl of a sink.
(6) Indoor Damp and Wet Locations. GFCI protection is required for all receptacles located in indoor damp and wet locations.
(7) Locker Rooms. GFCI protection is required for receptacles located in locker rooms with showering facilities.
(8) Garages and Similar Areas. GFCI protection is required for all receptacles located in garages, accessory buildings, service bays, and similar areas.
Author's Comment:
►According to Article 100, a Garage is a building or portion of a building in which one or more self-propelled vehicles can be kept for use, sale, storage, rental, repair, exhibition, or demonstration.
(9) Crawl Spaces. GFCI protection is required for all receptacles located in crawl spaces at or below grade level.
(10) Unfinished Areas of Basements. GFCI protection is required for all receptacles located in the unfinished areas of a basement.
(11) Laundry Areas. GFCI protection is required for all receptacles located in the laundry area.
(12) Bathtubs and Shower Stalls. GFCI protection is required for all receptacles installed within 6 ft of the outside edge of the bathtub or shower stall not installed in a bathroom as defined in Article 100.
Author's Comment:
►This addition is to cover receptacles installed within 6 ft from bathtubs or shower stalls that are not covered by one of the other list items. In nondwelling occupancies, the hazard is related to the tub and shower, not to where they may be physically located within the building. A hydro-massage unit might be in the corner of a physical therapy room for example.
Q3. What are the Code requirements for GFCI protection of appliances?
A3. 422.5 GFCI Protection
(A) General. The following appliances rated 150 volts-to-ground or less and 60A or less must be GFCI protected by Class A protective device(s), [422.5(B)].
(1) Automotive vacuum machines.
(2) Drinking water coolers and bottle fill stations.
(3) Cord-and-plug-connected high-pressure spray washing machines.
(4) Tire inflation machines.
(5) Vending machines.
(6) Sump pumps.
(7) Dishwashers.
Informational Note: Section 210.8 specifies requirements for GFCI protection for the receptacle outlets where the location warrants such protection.
(B) Type and Location. The GFCI must be readily accessible and located in one or more of the following locations:
(1) A GFCI circuit breaker,
(2) A GFCI device or receptacle,
(3) A GFCI integral with the attachment plug,
(4) A GFCI within the supply cord not more than 12 in. from the attachment plug, or
(5) A factory installed GFCI within the appliance.
Author's Comment:
►The additional reference to Class A GFCIs seems to be redundant as Article 100 defines a GFCI stating that the device must comply with the time current trip requirements that have been established for a Class A device. As a result of that definition, anytime the NEC requires GFCI protection, it must be provided by a Class A GFCI.
Q4. What is the Code requirement for surge protection of dwelling unit services?
A4. 230.67 Surge Protection
(A) Surge-protective Device. All services suppling dwelling units must be provided with a surge protective device. [230.67]
(B) Location. The surge-protective device must be an integral part of the service disconnect or be located immediately adjacent to the service disconnect.
Ex: The surge-protective device is permitted to be located in the downstream panelboard.
Author's Comment:
►An example of where the exception could be applied is where there is an exterior meter main that feeds an interior panel. The surge-protective device could be installed at the interior panel using the exception.
►See Parts I and II of Article 242 for the installation requirements that apply to surge-protective devices.
(C) Type. The surge-protective device must be a Type 1 or Type 2 surge-protective device.
(D) Replacement. Where service equipment is replaced, surge protection must be installed.
Q5. What Code rule applies to the number of service disconnects allowed on a service?
A5. 230.71 Number of Service Disconnects
Each service must have only one disconnecting means except as permitted in 230.71(B).
(A) General. For the purpose of this section, a disconnecting means installed as part of listed equipment and used solely for the following is not considered a service disconnecting means:
(1) Power monitoring equipment.
(2) Surge-protective device(s).
(3) Control circuit of the ground-fault protection system.
(4) Power-operable service disconnect.
(B) Two to Six Service Disconnecting Means. Up to six service disconnects are permitted for each service allowed by 230.2, or for each set of service-entrance conductors permitted by 230.40 Ex 1, 3, 4, or 5.
The two to six service disconnecting means may consist of a combination of any of the following:
(1) Separate enclosures with a main service disconnecting means in each enclosure
(2) Panelboards with a main service disconnecting means in each panelboard
(3) Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section
(4) Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment
Informational Note 2: Examples of separate enclosures with main service disconnecting means in each enclosure include but are not limited to, motor control centers, fused disconnects, circuit breaker enclosures, and transfer switches that are suitable for use as service equipment.
Author's Comment:
►The rule is six disconnects for each service, not for each building. If the building has two services, then there can be a total of 12 service disconnects (six disconnects per service).
Author's Comment:
►This revision retains the previous permission to have 2 to 6 service disconnects for each service or each set of service-entrance conductors but provides the increase in safety that a single service disconnect provides. The previous six main disconnect rule for a single enclosure made it impossible to work in service equipment when applying electrical safe work practices in accordance with NFPA 70E, unless the line side of the multi-disconnect enclosure was disconnected by the utility.
►This revision also reflects the electrical hazards inherent while working on service equipment where there is more than one service disconnect in a single enclosure. This, combined with the rule in 230.62(C) that requires line side barriers, is a significant safety improvement towards reducing the risk to electricians by limiting their exposure to energized parts.
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