295 lines
11 KiB
Markdown
295 lines
11 KiB
Markdown
---
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id:
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aliases:
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- nec-210
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tags:
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- authorship/other
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- destiny/uncertain
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- status/incomplete
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- topic/electrical
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- type/encyclopedia
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title: NEC Article 210 Branch Circuits
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---
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# NEC Article 210 Branch Circuits
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## Part I. General Provisions
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### 210.1 Scope.
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This article provides the general requirements for branch circuits.
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<!-- TODO: TEXT OMITTED -->
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### 210.11 Branch Circuits Required.
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Branch circuits for lighting and for appliances,
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including motor-operated appliances,
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shall be provided to supply the loads calculated in accordance with 220.10.
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In addition, branch circuits shall be provided for specific loads not covered by 220.10
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where required elsewhere in this Code
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and for dwelling unit loads as specified in 210.11(C).
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#### 210.11(A) Number of Branch Circuits.
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The minimum number of branch circuits
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shall be determined from the total calculated load
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and the size or rating of the circuits used.
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In all installations, the number of circuits
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shall be sufficient to supply the load served.
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In no case shall the load on any circuit exceed the maximum specified by 220.18.
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#### 210.11(B) Load Evenly Proportioned Among Branch Circuits.
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Where the load is calculated on the basis of volt-amperes per square meter or per square foot,
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the wiring system up to and including the branch-circuit panelboard(s)
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shall be provided to serve not less than the calculated load.
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This load shall be evenly proportioned
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among multioutlet branch circuits within the panelboard(s).
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Branch-circuit overcurrent devices and circuits
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shall be required to be installed only to serve the connected load.
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#### 210.11(C) Dwelling Units.
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##### 210.11(C)(1) Small-Appliance Branch Circuits.
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In addition to the number of branch circuits required by other parts of this section,
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two or more 20-ampere small-appliance branch circuits shall be provided
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for all receptacle outlets specified by 210.52(B).
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##### 210.11(C)(2) Laundry Branch Circuits.
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In addition to the number of branch circuits required by other parts of this section,
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at least one additional 20-ampere branch circuit shall be provided
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to supply the laundry receptacle outlet(s) required by 210.52(F).
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This circuit shall have no other outlets.
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##### 210.11(C)(3) Bathroom Branch Circuits.
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In addition to the number of branch circuits required by other parts of this section,
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one or more 120-volt, 20-ampere branch circuit shall be provided
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to supply bathroom(s) receptacle outlet(s) required by 210.52(D)
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and any countertop and similar work surface receptacle outlets.
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Such circuits shall have no other outlets.
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Exception:
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Where the 20-ampere circuit supplies a single bathroom,
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outlets for other equipment within the same bathroom
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shall be permitted to be supplied in accordance with 210.23(A)(1) and (A)(2).
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##### 210.11(C)(4) Garage Branch Circuits.
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In addition to the number of branch circuits required by other parts of this section,
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at least one 120-volt, 20-ampere branch circuit shall be installed
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to supply receptacle outlets required by 210.52(G)(1)
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for attached garages and in detached garages with electric power.
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This circuit shall have no other outlets.
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Exception:
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This circuit shall be permitted to supply
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readily accessible outdoor receptacle outlets.
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<!-- TODO: TEXT OMITTED -->
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## Part II. Branch-Circuit Ratings
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### 210.18 Rating.
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Branch circuits recognized by this article
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shall be rated in accordance with the maximum permitted ampere rating
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or setting of the overcurrent device.
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The rating for other than individual branch circuits
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shall be 15, 20, 30, 40, and 50 amperes.
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Where conductors of higher ampacity are used for any reason,
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the ampere rating or setting of the specified overcurrent device
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shall determine the circuit rating.
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> [!important] Exception:
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> Multioutlet branch circuits greater than 50 amperes
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> shall be permitted to supply nonlighting outlet loads on industrial premises
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> where conditions of maintenance and supervision ensure
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> that only qualified persons service the equipment.
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### 210.19 Conductors -- Minimum Ampacity and Size.
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<!-- TODO: TEXT OMITTED -->
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#### 210.19(A) Branch Circuits Not More Than 600 Volts.
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##### 210.19(A)(1) General.
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Branch-circuit conductors shall have an ampacity
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not less than the larger of 210.19(A)(1)(a) or (A)(1)(b)
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and comply with
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[[nfpa-70_110_requirements-for-electrical-installations#110.14(C) Temperature Limitations.|110.14(C)]]
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for equipment terminations.
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* (a) Where a branch circuit supplies continuous loads
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or any combination of continuous and noncontinuous loads,
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the minimum branch-circuit conductor size
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shall have an ampacity not less than the noncontinuous load
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plus 125 percent of the continuous load in accordance with
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[[nfpa-70_310_conductors_for_general_wiring#310.14 Ampacities for Conductors Rated 0 Volts – 2000 Volts.|310.14]].
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* (b) The minimum branch-circuit conductor size
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shall have an ampacity not less than the maximum load to be served
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after the application of any adjustment
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or correction factors in accordance with
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[[nfpa-70_310_conductors_for_general_wiring#310.15 Ampacity Tables.|310.15]].
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##### 210.19(A)(2) Branch Circuits with More than One Receptacle.
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Conductors of branch circuits supplying more than one receptacle
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for cord-and-plug-connected portable loads
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shall have an ampacity of not less than the rating of the branch circuit.
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<!-- TODO: TEXT OMITTED -->
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### 210.21 Outlet Devices.
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Outlet devices shall have an ampere rating
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that is not less than the load to be served
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and shall comply with 210.21(A) and (B).
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#### 210.21(A) Lampholders.
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Where connected to a branch circuit having a rating in excess of 20 amperes, lampholders
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shall be of the heavy-duty type. A heavy-duty lampholder
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shall have a rating of not less than 660 watts if of the admedium type,
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or not less than 750 watts if of any other type.
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#### 210.21(B) Receptacles.
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##### 210.21(B)(1) Single Receptacle on an Individual Branch Circuit.
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A single receptacle installed on an individual branch circuit
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shall have an ampere rating
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not less than that of the branch circuit.
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> [!important] Exception No. 1:
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> A receptacle installed in accordance with 430.81(B).
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> [!important] Exception No. 2:
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> A receptacle installed exclusively for the use of a cord-and-plug-connected arc welder
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> shall be permitted to have an ampere rating
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> not less than the minimum branch-circuit conductor ampacity
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> determined by 630.11(A) for arc welders.
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> [!info] Informational Note:
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> See the definition of receptacle in Article 100.
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##### 210.21(B)(2) Total Cord-and-Plug-Connected Load.
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Where connected to a branch circuit supplying two or more receptacles or outlets,
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a receptacle shall not supply a total cord-and-plug-connected load
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in excess of the maximum specified in Table 210.21(B)(2).
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##### Table 210.21(B)(2) Maximum Cord-and-Plug-Connected Load to Receptacle
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| Circuit Rating (Amperes) | Receptacle Rating (Amperes) | Maximum Load (Amperes) |
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| ------------------------ | --------------------------- | ---------------------- |
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| 15 or 20 | 15 | 12 |
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| 20 | 20 | 16 |
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| 30 | 30 | 24 |
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##### 210.21(B)(3) Receptacle Ratings.
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Where connected to a branch circuit supplying two or more receptacles or outlets,
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receptacle ratings shall conform to the values listed in Table 210.21(B)(3),
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or, where rated higher than 50 amperes,
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the receptacle rating shall not be less than the branch-circuit rating.
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> [!important] Exception No. 1:
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> Receptacles installed exclusively
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> for the use of one or more cord-and-plug-connected arc welders
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> shall be permitted to have ampere ratings
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> not less than the minimum branch-circuit conductor ampacity
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> determined by 630.11(A) or (B) for arc welders.
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> [!important] Exception No. 2:
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> The ampere rating of a receptacle
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> installed for electric discharge lighting
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> shall be permitted to be based on 410.62(C).
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##### Table 210.21(B)(3) Receptacle Ratings for Various Size Circuits
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| Circuit Rating (Amperes) | Receptacle Rating (Amperes) |
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| ------------------------ | --------------------------- |
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| 15 | Not over 15 |
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| 20 | 15 or 20 |
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| 30 | 30 |
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| 40 | 40 or 50 |
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| 50 | 50 |
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##### 210.21(B)(4) Range Receptacle Rating.
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The ampere rating of a range receptacle
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shall be permitted to be based on a single range demand load
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as specified in Table 220.55.
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### 210.22 Permissible Loads, Individual Branch Circuits.
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An individual branch circuit
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shall be permitted to supply any load for which it is rated,
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but in no case shall the load exceed the branch-circuit ampere rating.
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### 210.23 Permissible Loads, Multiple-Outlet Branch Circuits.
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In no case shall the load exceed the branch-circuit ampere rating.
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A branch circuit supplying two or more outlets or receptacles
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shall supply only the loads specified according to its size
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as specified in 210.23(A) through (D)
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and as summarized in 210.24 and Table 210.24.
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#### 210.23(A) 15- and 20-Ampere Branch Circuits.
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A 15- or 20-ampere branch circuit
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shall be permitted to supply lighting units
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or other utilization equipment,
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or a combination of both,
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and shall comply with 210.23(A)(1) and (A)(2).
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> [!important] Exception:
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> The small-appliance branch circuits,
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> laundry branch circuits, and bathroom branch circuits
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> required in a dwelling unit(s) by 210.11(C)(1), (C)(2), and (C)(3)
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> shall supply only the receptacle outlets specified in that section.
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##### 210.23(A)(1) Cord-and-Plug-Connected Equipment Not Fastened in Place.
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The rating of any one cord-and-plug-connected utilization equipment not fastened in place
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shall not exceed 80 percent of the branch-circuit ampere rating.
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##### 210.23(A)(2) Utilization Equipment Fastened in Place.
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The total rating of utilization equipment fastened in place, other than luminaires,
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shall not exceed 50 percent of the branch-circuit ampere rating
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where lighting units, cord-and-plug-connected utilization equipment not fastened in place,
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or both, are also supplied.
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#### 210.23(B) 30-Ampere Branch Circuits.
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A 30-ampere branch circuit
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shall be permitted to supply fixed lighting units
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with heavy-duty lampholders in other than a dwelling unit(s)
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or utilization equipment in any occupancy.
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A rating of any one cord-and-plug-connected utilization equipment
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shall not exceed 80 percent of the branch-circuit ampere rating.
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##### 210.23(C) 40and 50-Ampere Branch Circuits.
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A 40- or 50-ampere branch circuit
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shall be permitted to supply cooking appliances
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that are fastened in place in any occupancy.
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In other than dwelling units,
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such circuits shall be permitted to supply
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fixed lighting units with heavy-duty lampholders,
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infrared heating units,
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or other utilization equipment.
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#### 210.23(D) Branch Circuits Larger Than 50 Amperes.
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Branch circuits larger than 50 amperes
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shall supply only nonlighting outlet loads.
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