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NEC Article 210: Branch Circuits |
NEC Article 210: Branch Circuits
Part I. General Provisions
210.1 Scope.
This article provides the general requirements for branch circuits.
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).
210.11(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 220.18.
210.11(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.
210.11(C) Dwelling Units.
210.11(C)(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).
210.11(C)(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.
210.11(C)(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(A)(1) and (A)(2).
210.11(C)(4) Garage Branch Circuits.
In addition to the number of branch circuits required by other parts of this section, at least one 120-volt, 20-ampere branch circuit shall be installed to supply receptacle outlets required by 210.52(G)(1) for attached garages and in detached garages with electric power. This circuit shall have no other outlets.
Exception: This circuit shall be permitted to supply readily accessible outdoor receptacle outlets.
Part II. Branch-Circuit Ratings
210.18 Rating.
Branch circuits recognized by this article shall be rated in accordance with the maximum permitted ampere rating or setting of the overcurrent device. The rating for other than individual branch circuits shall be 15, 20, 30, 40, and 50 amperes. Where conductors of higher ampacity are used for any reason, the ampere rating or setting of the specified overcurrent device shall determine the circuit rating.
[!important] Exception: Multioutlet branch circuits greater than 50 amperes shall be permitted to supply nonlighting outlet loads on industrial premises where conditions of maintenance and supervision ensure that only qualified persons service the equipment.
210.19 Conductors -- Minimum Ampacity and Size.
210.19(A) Branch Circuits Not More Than 600 Volts.
210.19(A)(1) General.
Branch-circuit conductors shall have an ampacity not less than the larger of 210.19(A)(1)(a) or (A)(1)(b) and comply with nfpa-70_110_requirements-for-electrical-installations#110.14(C) Temperature Limitations. for equipment terminations.
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(a) Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the minimum branch-circuit conductor size shall have an ampacity not less than the noncontinuous load plus 125 percent of the continuous load in accordance with nfpa-70_310_conductors_for_general_wiring#310.14 Ampacities for Conductors Rated 0 Volts – 2000 Volts..
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(b) The minimum branch-circuit conductor size shall have an ampacity not less than the maximum load to be served after the application of any adjustment or correction factors in accordance with nfpa-70_310_conductors_for_general_wiring#310.15 Ampacity Tables..
210.19(A)(2) Branch Circuits with More than One Receptacle.
Conductors of branch circuits supplying more than one receptacle for cord-and-plug-connected portable loads shall have an ampacity of not less than the rating of the branch circuit.
210.21 Outlet Devices.
Outlet devices shall have an ampere rating that is not less than the load to be served and shall comply with 210.21(A) and (B).
210.21(A) Lampholders.
Where connected to a branch circuit having a rating in excess of 20 amperes, lampholders shall be of the heavy-duty type. A heavy-duty lampholder shall have a rating of not less than 660 watts if of the admedium type, or not less than 750 watts if of any other type.
210.21(B) Receptacles.
210.21(B)(1) Single Receptacle on an Individual Branch Circuit.
A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.
[!important] Exception No. 1: A receptacle installed in accordance with 430.81(B).
[!important] Exception No. 2: A receptacle installed exclusively for the use of a cord-and-plug-connected arc welder shall be permitted to have an ampere rating not less than the minimum branch-circuit conductor ampacity determined by 630.11(A) for arc welders.
[!info] Informational Note: See the definition of receptacle in Article 100.
210.21(B)(2) Total Cord-and-Plug-Connected Load.
Where connected to a branch circuit supplying two or more receptacles or outlets, a receptacle shall not supply a total cord-and-plug-connected load in excess of the maximum specified in Table 210.21(B)(2).
Table 210.21(B)(2) Maximum Cord-and-Plug-Connected Load to Receptacle
| Circuit Rating (Amperes) | Receptacle Rating (Amperes) | Maximum Load (Amperes) |
|---|---|---|
| 15 or 20 | 15 | 12 |
| 20 | 20 | 16 |
| 30 | 30 | 24 |
210.21(B)(3) Receptacle Ratings.
Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle ratings shall conform to the values listed in Table 210.21(B)(3), or, where rated higher than 50 amperes, the receptacle rating shall not be less than the branch-circuit rating.
[!important] Exception No. 1: Receptacles installed exclusively for the use of one or more cord-and-plug-connected arc welders shall be permitted to have ampere ratings not less than the minimum branch-circuit conductor ampacity determined by 630.11(A) or (B) for arc welders.
[!important] Exception No. 2: The ampere rating of a receptacle installed for electric discharge lighting shall be permitted to be based on 410.62(C).
Table 210.21(B)(3) Receptacle Ratings for Various Size Circuits
| Circuit Rating (Amperes) | Receptacle Rating (Amperes) |
|---|---|
| 15 | Not over 15 |
| 20 | 15 or 20 |
| 30 | 30 |
| 40 | 40 or 50 |
| 50 | 50 |
210.21(B)(4) Range Receptacle Rating.
The ampere rating of a range receptacle shall be permitted to be based on a single range demand load as specified in Table 220.55.
210.22 Permissible Loads, Individual Branch Circuits.
An individual branch circuit shall be permitted to supply any load for which it is rated, but in no case shall the load exceed the branch-circuit ampere rating.
210.23 Permissible Loads, Multiple-Outlet Branch Circuits.
In no case shall the load exceed the branch-circuit ampere rating. A branch circuit supplying two or more outlets or receptacles shall supply only the loads specified according to its size as specified in 210.23(A) through (D) and as summarized in 210.24 and Table 210.24.
210.23(A) 15- and 20-Ampere Branch Circuits.
A 15- or 20-ampere branch circuit shall be permitted to supply lighting units or other utilization equipment, or a combination of both, and shall comply with 210.23(A)(1) and (A)(2).
[!important] Exception: The small-appliance branch circuits, laundry branch circuits, and bathroom branch circuits required in a dwelling unit(s) by 210.11(C)(1), (C)(2), and (C)(3) shall supply only the receptacle outlets specified in that section.
210.23(A)(1) Cord-and-Plug-Connected Equipment Not Fastened in Place.
The rating of any one cord-and-plug-connected utilization equipment not fastened in place shall not exceed 80 percent of the branch-circuit ampere rating.
210.23(A)(2) Utilization Equipment Fastened in Place.
The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord-and-plug-connected utilization equipment not fastened in place, or both, are also supplied.
210.23(B) 30-Ampere Branch Circuits.
A 30-ampere branch circuit shall be permitted to supply fixed lighting units with heavy-duty lampholders in other than a dwelling unit(s) or utilization equipment in any occupancy. A rating of any one cord-and-plug-connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating.
210.23(C) 40and 50-Ampere Branch Circuits.
A 40- or 50-ampere branch circuit shall be permitted to supply cooking appliances that are fastened in place in any occupancy. In other than dwelling units, such circuits shall be permitted to supply fixed lighting units with heavy-duty lampholders, infrared heating units, or other utilization equipment.
210.23(D) Branch Circuits Larger Than 50 Amperes.
Branch circuits larger than 50 amperes shall supply only nonlighting outlet loads.
Part III. Required Outlets
210.50 Receptacle Outlets.
nfpa-70_100_definitions#Receptacle Outlet. shall be installed as specified in 210.52 through 210.65.
Informational Note: See Informative Annex J for information regarding ADA accessibility design.
210.50(A) Cord Pendants.
A nfpa-70_100_definitions#Cord Connector. that is supplied by a permanently connected cord pendant shall be considered a receptacle outlet.
210.50(B) Cord Connections.
A receptacle outlet shall be installed wherever flexible cords with attachment plugs are used. Where flexible cords are permitted to be permanently connected, receptacles shall be permitted to be omitted for such cords.
210.50(C) Appliance Receptacle Outlets.
nfpa-70_100_definitions#Appliance. receptacle outlets installed in a nfpa-70_100_definitions#Dwelling Unit. for specific appliances, such as laundry equipment, shall be installed within 1.8 m (6 ft) of the intended location of the appliance.
210.52 Dwelling Unit Receptacle Outlets.
This section provides requirements for 125-volt, 15- and 20-ampere receptacle outlets. The receptacles required by this section shall be in addition to any receptacle that is as follows:
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Part of a luminaire or appliance, or
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Controlled by a listed wall-mounted control device in accordance with 210.70(A)(1), Exception No. 1, or
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Located within cabinets or cupboards, or
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Located more than 1.7 m (5 1⁄2 ft) above the floor
Permanently installed electric baseboard heaters equipped with factory-installed receptacle outlets or outlets provided as a separate assembly by the manufacturer shall be permitted as the required outlet or outlets for the wall space utilized by such permanently installed heaters. Such receptacle outlets shall not be connected to the heater circuits.
Informational Note: Listed baseboard heaters include instructions that may not permit their installation below receptacle outlets.
210.52(A) General Provisions.
In every kitchen, family room, dining room, living room, parlor, library, den, sunroom, bedroom, recreation room, or similar room or area of dwelling units, receptacle outlets shall be installed in accordance with the general provisions specified in 210.52(A)(1) through (A)(4).
210.52(A)(1) Spacing.
Receptacles shall be installed such that no point measured horizontally along the floor line of any wall space is more than 1.8 m (6 ft) from a receptacle outlet.
210.52(A)(2) Wall Space.
As used in this section, a wall space shall include the following:
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Any space 600 mm (2 ft) or more in width (including space measured around corners) and unbroken along the floor line by doorways and similar openings, fireplaces, and fixed cabinets that do not have countertops or similar work surfaces
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The space occupied by fixed panels in walls, excluding sliding panels
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The space afforded by fixed room dividers, such as freestanding bar-type counters or railings
210.52(A)(3) Floor Receptacles.
Receptacle outlets in or on floors shall not be counted as part of the required number of receptacle outlets unless located within 450 mm (18 in.) of the wall.
210.52(A)(4) Countertop and Similar Work Surface Receptacle Outlets.
Receptacles installed for countertop and similar work surfaces as specified in 210.52(C) shall not be considered as the receptacle outlets required by 210.52(A).
210.52(B) Small Appliances.
210.52(B)(1) Receptacle Outlets Served.
In the kitchen, pantry, breakfast room, dining room, or similar area of a dwelling unit, the two or more 20-ampere small-appliance branch circuits required by 210.11(C)(1) shall serve all wall and floor receptacle outlets covered by 210.52(A), all countertop outlets covered by 210.52(C), and receptacle outlets for refrigeration equipment.
Exception No. 1: In addition to the required receptacles specified by 210.52, switched receptacles supplied from a general-purpose 15- or 20-ampere branch circuit as required in 210.70(A)(1), Exception No. 1, shall be permitted.
Exception No. 2: In addition to the required receptacles specified by 210.52, a receptacle outlet to serve a specific appliance shall be permitted to be supplied from an individual branch circuit rated 15 amperes or greater.
210.52(B)(2) No Other Outlets.
The two or more small-appliance branch circuits specified in 210.52(B)(1) shall have no other outlets.
Exception No. 1: A receptacle installed solely for the electrical supply to and support of an electric clock in any of the rooms specified in 210.52(B)(1).
Exception No. 2: Receptacles installed to provide power for supplemental equipment and lighting on gas-fired ranges, ovens, or counter-mounted cooking units.
210.52(B)(3) Kitchen Receptacle Requirements.
Receptacles installed in a kitchen to serve countertop surfaces shall be supplied by not fewer than two small-appliance branch circuits, either or both of which shall also be permitted to supply receptacle outlets in the same kitchen and in other rooms specified in 210.52(B)(1). Additional small-appliance branch circuits shall be permitted to supply receptacle outlets in the kitchen and other rooms specified in 210.52(B)(1). No small-appliance branch circuit shall serve more than one kitchen.
210.52(C) Countertops and Work Surfaces.
In kitchens, pantries, breakfast rooms, dining rooms, and similar areas of dwelling units, receptacle outlets for countertop and work surfaces that are 300 mm (12 in.) or wider shall be installed in accordance with 210.52(C)(1) through (C)(3) and shall not be considered as the receptacle outlets required by 210.52(A).
For the purposes of this section, where using multioutlet assemblies, each 300 mm (12 in.) of multioutlet assembly containing two or more receptacles installed in individual or continuous lengths shall be considered to be one receptacle outlet.
210.52(C)(1) Wall Spaces.
Receptacle outlets shall be installed so that no point along the wall line is more than 600 mm (24 in.) measured horizontally from a receptacle outlet in that space.
Exception: Receptacle outlets shall not be required directly behind a range, counter-mounted cooking unit, or sink in the installation described in Figure 210.52(C)(1).
^210.52(C)(1), Exception
Figure 210.52(C)(1) Determination of Area Behind a Range, Counter-Mounted Cooking Unit, or Sink.
210.52(C)(2) Island and Peninsular Countertops and Work Surfaces.
Receptacle outlets shall be installed in accordance with 210.52(C)(2)(a) and (C)(2)(b).
(a) At least one receptacle outlet shall be provided for the first 0.84 m (9 ft), or fraction thereof, of the countertop or work surface. A receptacle outlet shall be provided for every additional 1.7 m (18 ft), or fraction thereof, of the countertop or work surface.
(b) At least one receptacle outlet shall be located within 600 mm (2 ft) of the outer end of a peninsular countertop or work surface.
Additional required receptacle outlets shall be permitted to be located as determined by the installer, designer, or building owner.
The location of the receptacle outlets shall be in accordance with 210.52(C)(3).
A peninsular countertop shall be measured from the connected perpendicular wall.
210.52(C)(3) Receptacle Outlet Location.
Receptacle outlets shall be located in one or more of the following:
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On or above countertop or work surfaces: On or above, but not more than 500 mm (20 in.) above, the countertop or work surface.
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In countertop or work surfaces: Receptacle outlet assemblies listed for use in countertops or work surfaces shall be permitted to be installed in countertops or work surfaces.
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Below countertop or works surfaces: Not more than 300 mm (12 in.) below the countertop or work surface. Receptacles installed below a countertop or work surface shall not be located where the countertop or work surface extends more than 150 mm (6 in.) beyond its support base.
Receptacle outlets rendered not readily accessible by appliances fastened in place, appliance garages, sinks, or rangetops as covered in 210.52(C)(1), Exception, or appliances occupying assigned spaces shall not be considered as these required outlets.
Informational Note No. 1: See 406.5(E) and 406.5(G) for installation of receptacles in countertops and 406.5(F) and 406.5(G) for installation of receptacles in work surfaces. See 380.10 for installation of multioutlet assemblies.
Informational Note No. 2: See Annex J and ANSI/ICC A117.1-2009, Standard on Accessible and Usable Buildings and Facilities.
210.52(D) Bathrooms.
At least one receptacle outlet shall be installed in nfpa-70_100_definitions#Bathroom. within 900 mm (3 ft) of the outside edge of each basin. The receptacle outlet shall be located on a wall or partition that is adjacent to the basin or basin countertop, located on the countertop, or installed on the side or face of the basin cabinet. In no case shall the receptacle be located more than 300 mm (12 in.) below the top of the basin or basin countertop. Receptacle outlet assemblies listed for use in countertops shall be permitted to be installed in the countertop.
Informational Note: See 406.5(E) and 406.5(G) for requirements for installation of receptacles in countertops.
210.52(E) Outdoor Outlets.
Outdoor receptacle outlets shall be installed in accordance with 210.52(E)(1) through (E)(3).
Informational Note: See 210.8(A)(3).
210.52(E)(1) One-Family and Two-Family Dwellings.
For a one-family dwelling and each unit of a two-family dwelling that is at grade level, at least one receptacle outlet readily accessible from grade and not more than 2.0 m (6 1⁄2 ft) above grade level shall be installed at the front and back of the dwelling.
210.52(E)(2) Multifamily Dwellings.
For each dwelling unit of a multifamily dwelling where the dwelling unit is located at grade level and provided with individual exterior entrance/egress, at least one receptacle outlet readily accessible from grade and not more than 2.0 m (6 1⁄2 ft) above grade level shall be installed.
210.52(E)(3) Balconies, Decks, and Porches.
Balconies, decks, and porches that are within 102 mm (4 in.) horizontally of the dwelling unit shall have at least one receptacle outlet accessible from the balcony, deck, or porch. The receptacle outlet shall not be located more than 2.0 m (6 1⁄2 ft) above the balcony, deck, or porch walking surface.
210.52(F) Laundry Areas.
In dwelling units, at least one receptacle outlet shall be installed in areas designated for the installation of laundry equipment.
Exception No. 1: A receptacle for laundry equipment shall not be required in a dwelling unit of a multifamily building where laundry facilities are provided on the premises for use by all building occupants.
Exception No. 2: A receptacle for laundry equipment shall not be required in other than one-family dwellings where laundry facilities are not to be installed or permitted.
210.52(G) Basements, Garages, and Accessory Buildings.
For one and two-family dwellings, and multifamily dwellings, at least one receptacle outlet shall be installed in the areas specified in 210.52(G)(1) through (G)(3). These receptacles shall be in addition to receptacles required for specific equipment.
210.52(G)(1) Garages.
In each attached garage and in each detached garage with electric power, at least one receptacle outlet shall be installed in each vehicle bay and not more than 1.7 m (5 1⁄2 ft) above the floor.
Exception: Garage spaces not attached to an individual dwelling unit of a multifamily dwelling shall not require a receptacle outlet in each vehicle bay.
210.52(G)(2) Accessory Buildings.
In each accessory building with electric power.
210.52(G)(3) Basements.
In each separate unfinished portion of a basement.
210.52(H) Hallways.
In dwelling units, hallways of 3.0 m (10 ft) or more in length shall have at least one receptacle outlet.
As used in this subsection, the hallway length shall be considered the length along the centerline of the hallway without passing through a doorway.
210.52(I) Foyers.
Foyers that are not part of a hallway in accordance with 210.52(H) and that have an area that is greater than 5.6 m (60 ft ) shall have a receptacle(s) located in each wall space 900 mm (3 ft) or more in width. Doorways, door-side windows that extend to the floor, and similar openings shall not be considered wall space.
210.60 Guest Rooms, Guest Suites, Dormitory Units, and Similar Occupancies.
210.60(A) General.
Guest rooms or guest suites in hotels or motels, sleeping rooms in dormitory units, and similar occupancies shall have receptacle outlets installed in accordance with 210.52(A) and (D). Guest rooms or guest suites provided with permanent provisions for cooking shall have receptacle outlets installed in accordance with all of the applicable rules in 210.52.
210.60(B) Receptacle Placement.
The total number of receptacle outlets shall not be less than required in #210.52(A) General Provisions. These receptacle outlets shall be permitted to be located conveniently for permanent furniture layout. At least two receptacle outlets shall be readily accessible. Where receptacles are installed behind the bed, the receptacle shall be located to prevent the bed from contacting any attachment plug that may be installed or the receptacle shall be provided with a suitable guard.
210.62 Show Windows.
At least one 125-volt, single-phase, 15- or 20-ampere-rated receptacle outlet shall be installed within 450 mm (18 in.) of the top of a show window for each 3.7 linear m (12 linear ft) or major fraction thereof of show window area measured horizontally at its maximum width.
210.63 Equipment Requiring Servicing.
A 125-volt, single-phase, 15- or 20-ampere-rated receptacle outlet shall be installed at an accessible location within 7.5 m (25 ft) of the equipment as specified in 210.63(A) and (B).
210.63(A) Heating, Air-Conditioning, and Refrigeration Equipment.
The required receptacle outlet shall be located on the same level as the heating, air-conditioning, and refrigeration equipment. The receptacle outlet shall not be connected to the load side of the equipment's branch-circuit disconnecting means.
Exception: A receptacle outlet shall not be required at one- and two-family dwellings for the service of evaporative coolers.
210.63(B) Other Electrical Equipment.
In other than one and two-family dwellings, a receptacle outlet shall be located as specified in 210.63(B)(1) and (B)(2).
210.63(B)(1) Indoor Service Equipment.
The required receptacle outlet shall be located within the same room or area as the service equipment.
210.63(B)(2) Indoor Equipment Requiring Dedicated Equipment Spaces.
Where equipment, other than service equipment, requires dedicated equipment space as specified in nfpa-70_110_requirements-for-electrical-installations#110.26(E) Dedicated Equipment Space., the required receptacle outlet shall be located within the same room or area as the electrical equipment and shall not be connected to the load side of the equipment's branch-circuit disconnecting means.