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---
id:
aliases:
- nec-210
tags:
- authorship/other
- destiny/uncertain
- status/incomplete
- topic/electrical
- type/encyclopedia
---
# NEC Article 210 Branch Circuits
## Part I. General Provisions
### 210.1 Scope.
This article provides the general requirements for branch circuits.
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### 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.
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## 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.
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#### 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.|110.14(C)]]
for equipment terminations.
* (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.|310.14]].
* (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.|310.15]].
##### 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.
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### 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.
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