xau

safety check, GFCIs installed to protect the receptacles covered in 210.8(A) and (B) are required to be readily accessible. GFCIs operate on fault currents of 4 to 6 milliamperes. At trip levels of 5 milliamperes (the instantaneous current could be much higher), a shock can be felt during the fault....

safety check, GFCIs installed to protect the receptacles covered in 210.8(A) and (B) are required to be readily accessible. GFCIs operate on fault currents of 4 to 6 milliamperes. At trip levels of 5 milliamperes (the instantaneous current could be much higher), a shock can be felt during the fault. The shock can lead to an involuntary reaction that could cause a secondary accident such as a fall. GFCIs do not protect persons from shock hazards where contact is made with the ungrounded (hot) and grounded (neutral) conductors or between different ungrounded (hot) conductors. Although 210.8 is the main rule for GFCIs, other specific applications that require the use of GFCIs are listed in the table below. Dwelling Units. All 125-volt through 250-volt receptacles installed in the following locations and supplied by single-phase branch circuits rated 150 volts or less to ground shall have ground-fault circuit-interrupter protection for personnel: Bathrooms Garages and also accessory buildings that have a floor located at or below grade level not intended as habitable rooms and limited to storage areas, work areas, and areas of similar use Outdoors Crawl spaces - at or below grade level Basements Kitchens Areas with sinks and permanent provisions for food preparation, beverage preparation, or cooking Sinks - where receptacles are installed within 1.8 m (6 ft) from the top inside edge of the bowl of the sink Boathouses Bathtubs or shower stalls - where receptacles are instal?led within 1.8 m (6 ft) of the outside edge of the bathtub or shower stall Laundry areas Indoor damp and wet locations Exception No. 1: Receptacles that are not readily accessible and are supplied by a branch circuit dedicated to electric snow-melting, deicing, or pipeline and vessel heating equipment shall be permitted to be instal?led in accordance with 426.28 or 427.22, as applicable. Exception No. 2: A receptacle supplying only a permanently installed premises security system shall be permitted to omit ground-fault circuit-interrupter protection. Exception No. 3: Listed weight-supporting ceiling receptacles (WSCR) utilized in combination with compatible weight-supporting attachment fittings (WSAF) installed for the purpose of supporting a ceiling luminaire or ceiling-suspended fan shall be permitted to omit ground-fault circuit-interrupter protection. If a general- purpose convenience receptacle is integral to the ceiling luminaire or ceiling- suspended fan, GFCI protection shall be provided. Exception No. 4: Factory-installed receptacles that are not readily accessible and are mounted internally to bathroom exhaust fan assemblies shall not require GFCI protection unless required by the installation instructions or listing. Informational Note: See 760.41(B) and 760.121(B) for power supply requirements for fire alarm systems. ENHANCED CONTENT Collapse Bathrooms. All 125- through 250-volt, single-phase receptacles for cord- and-plug- connected equipment in bathrooms must have GFCI protection, including receptacles that are integral with luminaires. The term bathroom applies to the entire area, whether or not a separating door, as illustrated in the exhibit below, is present. If they are adjacent and in close proximity, one receptacle outlet, meeting the proximity requirement of 210.52(D) for each basin, can be used to meet the receptacle outlet location requirement as shown in the top half of the exhibit. The bottom half of the exhibit illustrates the requirements of 210.11(C)(3), which provides two acceptable supply circuit arrangements for the bathroom receptacle outlet(s). Garages. The requirement for GFCI protected receptacles in garages and sheds, as illustrated in the example below, improves safety for persons using portable handheld tools, string trimmers, snow blowers, and similar tools that might be connected to the receptacles. GFCI protection is also required because auto repair work and general workshop electrical tools are often used. There are no exceptions. All 125- through 250-volt, single-phase receptacles installed in garages must provide GFCI protection for the user of appliances or other equipment regardless of where the receptacle is located in the garage. Appliance leakage currents permitted by today’s product standards are far less than the operational threshold of a GFCI, so unwanted tripping is unlikely. Outdoors. The dwelling unit shown below, which has four outdoor receptacles, illustrates the requirement of 210.8(A)(3). Three receptacles must be provided with GFCI protection. The fourth receptacle, located adjacent to the gutter for the roof-mounted snow-melting cable, is not readily accessible and, therefore, is exempt from the GFCI requirements because of its dedicated function to supply the deicing equipment. This receptacle is, however, covered by the equipment ground-fault protection requirements of 426.28. See also 210.52(E) and 406.9(B)(1) enhanced content regarding the installation of outdoor receptacles in wet and damp locations. Basements. All 125- through 250-volt, single-phase receptacles in a basement, as shown in the exhibit below, must have GFCI protection. Conductive floor surfaces usually exist in finished and unfinished basements. Basements, whether finished or unfinished, are prone to moisture, including flooding. GFCI protection is now required in all basements of a dwelling unit. There is an exception for locking support-type receptacles used for luminaires and for paddle fans because these receptacles are not used for cord-and-plug- connected equipment. There is also an exception for receptacles for fire alarm and burglar systems. This correlates with the performance requirements covering fire alarm power supplies contained in NFPA 72, National Fire Alarm and Signaling Code. Kitchens. Due to the presence of water and multiple grounded surfaces in a kitchen, there is a higher risk of electric shock. A damaged cord, or faulty or mis-wired appliance, could result in exposed surfaces becoming energized and therefore creating a shock hazard. GFCI protection of all receptacles in a kitchen addresses this potentially dangerous condition. Consumer Product Safety Commission (CPSC) data between 2011 and 2020 reflect 104 electrocutions, 81 percent of which were associated with working on an appliance or equipment. All kitchen receptacles rated 125-volt through 250- volt and supplied by single-phase branch circuits rated 150 volts or less to ground are required to have GFCI protection, provided through the use of a GFCI circuit breaker or GFCI receptacle. See the exhibit below. Areas with sinks and permanent provisions for food preparation, beverage preparation, or cooking. Receptacles that meet the voltage requirements listed in 210.8(A) are required to have GFCI protection within an area that has both a sink and permanent provisions for food preparation, beverage preparation, or cooking. For example, all receptacles within a wet bar area would require GFCI protection based on having provisions for beverage preparation. The exhibit below illustrates receptacles installed within a wet bar area with a sink with permanent provisions for beverage preparation, therefore requiring GFCI protection. Sinks - where receptacles are installed within 1.8 m (6 ft) from the top inside edge of the bowl of the sink. Sinks in kitchens are not the only sinks where a ground-fault shock hazard exists; therefore, this requirement covers all sinks in a dwelling. This GFCI requirement is not limited to receptacles serving countertop surfaces; rather, it covers all 125- through 250-volt, single- phase receptacles within 6 feet of any point along the inside edge at the top of the sink bowl. Many appliances used in these locations are ungrounded, and the presence of water and grounded surfaces contributes to a condition of increased risk of electric shock. Bathtubs or shower stalls. In some instances, bathtubs and shower stalls are installed in areas that might not meet the NEC definition of a bathroom. Many of these areas have tile or other conductive, possibly grounded, floors. A shock hazard could be present. Laundry areas. GFCI protection of receptacles in laundry areas of dwelling units applies regardless of what the area or room is called. Wet clothes and puddles of water can pose a shock hazard to anyone using any appliance in a laundry area. Exception No. 3. The locking support and mounting receptacles generally are located on the ceiling or high on the wall and generally are not readily accessible. These receptacles are used for luminaires, paddle fans, or combination luminaire/paddle fan fixtures. The receptacle is not designed for use with flexible cords and attachment plugs. GFCI protection is required if the assembly supplied by the locking support and mounting device includes a receptacle to supply cord-and-plug-connected equipment. Other Than Dwelling Units. All 125-volt through 250-volt receptacles supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, and all receptacles supplied by three-phase branch circuits rated 150 volts or less to ground, 100 amperes or less, installed in the following locations shall be provided with GFCI protection: Bathrooms Kitchens Areas with sinks and permanent provisions for food preparation, beverage preparation, or cooking Buffet serving areas with permanent provisions for food serving, beverage serving, or cooking Rooftops Outdoors Sinks where receptacles or cord-and-plug-connected fixed or stationary appliances are installed within 1.8 m (6 ft) from the top inside edge of the bowl of the sink Indoor damp or wet locations Locker rooms with associated showering facilities Garages, accessory buildings, service bays, and similar areas other than vehicle exhibition halls and showrooms Crawl spaces at or below grade level Unfinished areas of basements Aquariums, bait wells, and similar open aquatic vessels or containers, such as tanks or bowls, where receptacles are installed within 1.8 m (6 ft.) from the top inside edge or rim or from the conductive support framing of the vessel or container Laundry areas Bathtubs and shower stalls where receptacles are installed within 1.8 m (6 ft) of the outside edge of the bathtub or shower stall Exception No. 1: Receptacles that are not readily accessible and are supplied by a branch circuit dedicated to electric snow-melting, deicing, or pipeline and vessel heating equipment shall be permitted to be installed in accordance with 426.28 or 427.22, as applicable. Exception No. 2: Receptacles on rooftops shall not be required to be readily accessible other than from the rooftop. Exception No. 3: Receptacles or cord-and-plug-connected fixed and stationary appliances installed within 1.8 m (6 ft) from the top inside edge of a bowl of a sink shall not be required to be GFCI protected in industrial establishments where the conditions of maintenance and supervision ensure that only qualified personnel are involved, an assured equipment grounding conductor program in accordance with 590.6(B)(2) shall be permitted for only those receptacle outlets used to supply equipment that would create a greater hazard if power is interrupted or that has a design not compatible with GFCI protection. Exception No. 4: Receptacles or cord-and-plug-connected fixed and stationary appliances installed within 1.8 m (6 ft) from the top inside edge of a bowl of a sink shall not be required to be GFCI protected in industrial laboratories where the receptacles are used to supply equipment if removal of power would introduce a greater hazard. Exception No. 5: Receptacles located in patient bed locations of Category 2 (general care) or Category 1 (critical care) spaces of health care facilities shall be permitted to comply with 517.21. Exception No. 6: Listed weight-supporting ceiling receptacles (WSCR) utilized in combination with compatible weight-supporting attachment fittings (WSAF) installed for the purpose of serving a ceiling luminaire or ceiling-suspended fan shall be permitted to omit GFCI protection. If a general-purpose convenience receptacle is integral to the ceiling luminaire or ceiling-suspended fan, GFCI protection shall be provided. ENHANCED CONTENT Collapse This requirement now applies to most single-phase receptacles in the areas listed in this section, including receptacles on 240-volt circuits. Most three- phase receptacles on 280Y/120-volt three-phase circuits in those areas would also require GFCI protection. Equipment connected to receptacles of the higher voltage and current ratings presents the same shock hazards as equipment connected to receptacles with lower voltage and current ratings. Bathrooms. Some motel and hotel bathrooms, like the one shown in the exhibit below, have the basin located outside the door to the room containing the tub, toilet, or shower. The NEC definition of bathroom uses the word “area,” so that the sink shown in the lower left section of the exhibit is considered as being in the bathroom and is, therefore, subject to the GFCI requirement. The exhibit also depicts the supply circuit requirement of 210.11(C)(3) for bathroom receptacle outlets. Kitchens. This requirement applies to single-phase and three-phase receptacles in kitchens, regardless of whether the receptacle serves countertop areas. Electrical accident data indicate that there are many electrical hazards in nondwelling kitchens, including poorly maintained electrical equipment, damaged cords, and wet floors. Requiring GFCI protection in those kitchens protects personnel who might be exposed to electric shock. The NEC definition of kitchen is “an area with a sink and permanent facilities for food preparation and cooking.” A portable cooking appliance (e.g., cord-and-plug-connected microwave oven or hot plate) does not constitute a permanent cooking facility. Kitchens in restaurants, hotels, schools, churches, dining halls, and similar facilities are covered by this requirement. Sinks where receptacles or cord-and-plug-connected fixed or stationary appliances are installed within 1.8 m (6 ft) from the top inside edge of the bowl of the sink. Item (7) covers receptacles installed near sinks in lunchrooms, janitors’ closets, classrooms, and all other areas not covered by the bathroom and kitchen requirements. The exhibit below shows one single- phase, 125-volt, 15-ampere receptacle installed within 6 feet of the top inside edge of the sink bowl that is covered by the GFCI requirement. The single- phase, 240-volt, 30-ampere receptacle to the right of the duplex receptacle is also subject to the GFCI requirement. GFCI protection would also be required for any 3-phase, 208Y/120-volt receptacles rated 100 amperes or less. Garages. This requirement covers all garages, not just those in which vehicle maintenance is expected to take place. Many commercial garages have receptacles installed for purposes other than the use of hand tools. For instance, winter temperatures in some areas necessitate the use of engine block heaters. Cord-and-plug-connected engine block heaters that are not listed could exceed the maximum leakage current requirements for appliances. If the receptacles are not GFCI protected, the frame of the vehicle could become energized, posing a shock hazard. Crawl Space Lighting Outlets. GFCI protection shall be provided for lighting outlets not exceeding 120 volts installed in crawl spaces. Specific Appliances. GFCI protection shall be provided for the branch circuit or outlet supplying the following appliances rated 150 volts or less to ground and 60 amperes or less, single- or 3-phase: Automotive vacuum machines Drinking water coolers and bottle fill stations High-pressure spray washing machines Tire inflation machines Vending machines Sump pumps Dishwashers Electric ranges Wall-mounted ovens Counter-mounted cooking units Clothes dryers Microwave ovens ENHANCED CONTENT Collapse For more information on GFCI protection of specific appliance types, see 422.5(A) and its enhanced content. Equipment Requiring Servicing. GFCI protection shall be provided for the receptacles required by 210.63. Outdoor Outlets. For dwellings, all outdoor outlets, other than those covered in 210.8(A), Exception No. 1, including outlets installed in the following locations, and supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, shall be provided with GFCI protection: Garages that have floors located at or below grade level Accessory buildings Boathouses If equipment supplied by an outlet covered under the requirements of this section is replaced, the outlet shall be supplied with GFCI protection. Exception No. 1: GFCI protection shall not be required on lighting outlets other than those covered in 210.8(C). Exception No. 2: GFCI protection shall not be required for listed HVAC equipment. This exception shall expire September 1, 2026. ENHANCED CONTENT Collapse See also Article 100 for the definition of the term outlet. 210.9 Circuits Derived from Autotransformers. Branch circuits shall not be derived from autotransformers unless the circuit supplied has a grounded conductor that is electrically connected to a grounded conductor of the system supplying the autotransformer. Exception No. 1: An autotransformer shall be permitted without the connection to a grounded conductor where transforming from a nominal 208 volts to a nominal 240-volt supply or similarly from 240 volts to 208 volts. Exception No. 2: In industrial occupancies, where conditions of maintenance and supervision ensure that only qualified persons service the installation, autotransformers shall be permitted to supply nominal 600-volt loads from nominal 480-volt systems, and 480-volt loads from nominal 600-volt systems, without the connection to a similar grounded conductor. ENHANCED CONTENT Collapse A buck-boost autotransformer provides a means of lowering (bucking) or raising (boosting) a supply line voltage by a small amount (usually no more than 20 percent). A buck-boost transformer has two primary windings (H1-H2 and H3-H4) connected to two secondary windings (X1-X2 and X3-X4). A single unit is used to buck/boost a single-phase voltage, but two or three units are used to buck/boost a 3-phase voltage. In the exhibit below, a 120-volt supply is derived from a 240-volt system. The grounded conductor of the primary system is electrically connected to the grounded conductor of the secondary system. The following exhibit illustrates a common application that utilizes Exception No. 1. This circuit derives a single-phase, 240-volt supply system for ranges, air conditioners, heating elements, and motors from a 3-phase, 208Y/120-volt source system. The boosted leg should not be used to supply line-to-neutral loads, because the boosted line-to-neutral voltage will be higher than 120 volts. Other common applications include increasing a single-phase, 240-volt source to a single-phase, 277-volt supply for lighting systems and transforming 240 volts to 208 volts for use with 208-volt appliances. See below. The following exhibit illustrates typical 3-phase buck-boost transformers connected to change 240 volts to 208 volts and vice versa. 210.10 Ungrounded Conductors Tapped from Grounded Systems. Two-wire dc circuits and ac circuits of two or more ungrounded conductors shall be permitted to be tapped from the ungrounded conductors of circuits that have a grounded neutral conductor. Switching devices in each tapped circuit shall have a pole in each ungrounded conductor. All poles of multipole switching devices shall manually switch together where such switching devices also serve as a disconnecting means as required by the following: * (1) 410.93 for double-pole switched lampholders * (2) 410.104(B) for electric-discharge lamp auxiliary equipment switching devices * (3) 422.31(B) for an appliance * (4) 424.20 for a fixed electric space-heating unit * (5) 426.51 for electric deicing and snow-melting equipment * (6) 430.85 for a motor controller * (7) 430.103 for a motor ENHANCED CONTENT Collapse In the exhibit that follows, the top half illustrates an ungrounded 2-wire branch circuit tapped from the ungrounded conductors of a dc or single-phase system to supply a small motor. The bottom half illustrates a 3-phase, 4-wire wye system. Based on the characteristics of the depicted loads (line-to-line connected) supplied by the tapped circuits, a neutral or grounded conductor is not required to be installed with the ungrounded conductors. Circuit breakers or switches used as the disconnecting means for the tapped branch circuit must open all poles simultaneously using only the manual operation of the disconnecting means. If switches and fuses are used and one fuse blows, or if circuit breakers (two single-pole circuit breakers with a handle tie) are used and one breaker trips, one pole could possibly remain closed. The intention is not to require a common trip of fuses or circuit breakers but rather to disconnect the ungrounded conductors of the branch circuit with one manual operation. For information on the use of identified handle ties with single-pole circuit breakers, see 240.15(B). 210.11 Branch Circuits Required. Branch circuits for lighting and for appliances, including motor-operated appliances, shall be provided to supply the loads calculated in accordance with 220.10. In addition, branch circuits shall be provided for specific loads not covered by 220.10 where required elsewhere in this Code and for dwelling unit loads as specified in 210.11(C). (A) Number of Branch Circuits. The minimum number of branch circuits shall be determined from the total calculated load and the size or rating of the circuits used. In all installations, the number of circuits shall be sufficient to supply the load served. In no case shall the load on any circuit exceed the maximum specified by 220.11. (B) Load Evenly Proportioned Among Branch Circuits. Where the load is calculated on the basis of volt-amperes per square meter or per square foot, the wiring system up to and including the branch-circuit panelboard(s) shall be provided to serve not less than the calculated load. This load shall be evenly proportioned among multioutlet branch circuits within the panelboard(s). Branch-circuit overcurrent devices and circuits shall be required to be installed only to serve the connected load. (C) Dwelling Units. (1) Small-Appliance Branch Circuits. In addition to the number of branch circuits required by other parts of this section, two or more 20-ampere small-appliance branch circuits shall be provided for all receptacle outlets specified by 210.52(B). (2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets. (3) Bathroom Branch Circuits. In addition to the number of branch circuits required by other parts of this section, one or more 120-volt, 20-ampere branch circuit shall be provided to supply bathroom(s) receptacle outlet(s) required by 210.52(D) and any countertop and similar work surface receptacle outlets. Such circuits shall have no other outlets. Exception: Where the 20-ampere circuit supplies a single bathroom, outlets for other equipment within the same bathroom shall be permitted to be supplied in accordance with 210.23(B)(1) and (B)(2). ENHANCED CONTENT Collapse The installation of a 20-ampere branch for the receptacles in each individual bathroom is not necessary. A single circuit can supply more than one bathroom. (4) Garage Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one 12