Reprinted with permission from NFPA 70-1968, the National

Electrical Code®, Copyright© 1967, National Fire

Protection Association, Quincy, MA 02269. This
reprinted material is not the complete and official
position of the National Fire Protection Association, on
the referenced subject which is represented only by the
standard in its entirety.

National Electrical Code® and NEC® are registered trademarks

of the National Fire Protection Association, Inc.,
Quincy, MA 02269.
ARTICLE 210 - BRANCH CIRCUITS

210-1. Scope. The provisions of this Article shall apply to

branch circuits supplying lighting or appliance loads or
combinations of such loads. Where motors, or motor-operated
appliances, are connected to any circuit supplying lighting or
other appliance loads, the provisions of both the Article and
Article 430 shall apply. Article 430 shall apply where branch
circuit supplies only motor loads.

210-2. Specific Purpose Branch Circuit. The provisions applying

to branch circuits referred to in the following list are
exceptions to the provisions of this Article or are supplementary
thereto, and shall apply to branch circuits supplying the loads
referred to therein:

Boat Harbor Wiring ......................... Section 555-2

Busways .................................... Section 364-8
Cranes and Hoists .......................... Section 610-42
Data Processing Systems .................... Section 645-2
Elevators, Dumbwaiters and Escalators ...... Section 620-61
Fixed Electric Space Heating Equipment ..... Section 424-3
Infrared Industrial Heating Equipment ...... Section 422-15, 424-3
Inductive and Dielectric Heat Generating
Equipment ................................ Article 665
Instruments ................................ Section 384-22
Motion Picture Studios and Similar
Locations ................................ Article 530
Motors and Motor Controllers ............... Article 430
Organs ..................................... Section 650-6
Remote-Control, Low-Energy Power, Low-
Voltage Power and Signal Circuits ........ Article 725
Signs and Outline Lighting ................. Section 600-6
Sound Recording and Reproduction ........... Section 640-6
Systems over 600 Volts ..................... Article 710
Systems under 50 Volts ..................... Article 720 Theaters
Theaters and Assembly Halls ................ Section 520-41, 520-
52
and 520-
62
Welders .................................... Article 630
X-ray Equipment ............................ Section 660-3

210-3. Classifications. Branch circuits recognized by this

Article shall be classified in accordance with the maximum
permitted rating or setting of the overcurrent device, and the
classification for other than individual branch circuits shall be
15, 20, 30, 40 and 50 amperes. When conductors of higher capacity
are used for any reason, the rating or setting of the specified
overcurrent device shall determine the circuit classification.
A. General Provisions

210-4. Multiwire Branch Circuits. Branch circuits recognized by

this Article may be installed as multiwire circuits. See Article
100 for Definition.

210-5. Color Code. Where installed in raceways, as aluminum

sheathed cable, as open word, or as concealed knob-and-tube work,
the conductors of multiwire branch circuits and two-wire branch
circuits connected to the same system shall conform to the
following color code. Three-wire circuits - one black, one white,
one red; four-wire circuits - one black, one white, one red, one
blue; five-wire circuits - one black, one white, one red, one
blue, one yellow. Where more than one multiwire branch circuit is
carried through a single raceway the ungrounded conductors of the
additional circuit may be of colors other than those specified.
All circuit conductors of the same color shall be connected to the
same ungrounded feeder conductor throughout the installation.

Any conductor intended solely for grounding purposes shall be

identified by a continuous green color or a continuous green color
with one or more yellow stripes unless it be bare. Branch circuit
conductors and equipment lead wires to which branch circuit
conductors attach having a continuous green color or a continuous
green color with one or more yellow stripes shall not be used for
other than grounding purposes.

The above is not intended to prohibit the use of a conductor

having a continuous green color or a continuous green color with
one or more yellow stripes as insulation for internal wiring of
equipment, except when such wiring serves as the lead wires to
which the branch circuit conductors attach.

See Section 200-7 for use of white or natural gray for

grounded or neutral conductors.
210-6. Voltage.

(a) Voltage to Ground. The voltage to ground on branch

circuits supplying lampholders, fixtures, or standard receptacles
of 15-ampere or less rating shall not exceed 150 volts, except as
follows:
 Exception No. 1. In industrial establishments or in stores
where the conditions of maintenance and supervision assure that
only competent individuals will service the lighting fixtures the
voltage of branch circuits which supply only lighting fixtures
that are equipped with mogul-base screw-shell lampholders or with
lampholders of other types approved for the application, mounted
not less than eight feet from the floor, which do not have switch
control as an integral part of the fixture shall not exceed 300
volts to ground.

Exception No. 2. In industrial establishments, office

buildings, schools, stores, and public and commercial areas of
other buildings, such as hotels or transportation terminals, the
voltage of branch circuits which supply only the ballasts for
electric discharge lamps mounted in permanently installed
fixtures, by other than screw-shell type lampholders, which do not
have manual switch control as integral part of the fixture shall
not exceed 300 volts to ground. Where screw-shell type
lampholders are used for electric discharge lamps the fixtures
shall be installed not less than eight feet from the floor.

Exception No. 3. No infrared industrial heating appliances

as described in Section 422-15.

Exception No. 4. In railway properties as described in

Section 110-19;

Exception No. 5. The branch circuits supplying the ballasts

for electric discharge lamps mounted in permanently installed
fixtures on pole for the illumination of areas such as highways,
bridges, athletic fields, parking lots, at a height not less than
22 feet, or on other structures such as tunnels at a height not
less than 18 feet, shall not exceed 500 volts between conductors
when installed as provided in Section 730-7(a).

(b) Voltage Between Conductors - Dwellings. In dwelling

occupancies, the voltage between conductors supplying lampholders
of the screw-shell type, receptacles, or appliances, shall not
exceed 150 volts, except as follows:

Exception: The voltage between conductors may exceed 150

volts when supplying only:

(1) Permanently connected appliances,

(2) Portable appliances of more than 1,380 watts,
(3) Portable motor-operated appliances of 1/4 horsepower
or greater rating.

(c) Voltage Drop. The size of the conductors for branch

circuits as defined in Article 100 should be such that the voltage
drop would not exceed 3 per cent to the farthest outlet for power,
heating, lighting, or combinations thereof. Providing further
that the maximum total voltage drop for feeders, and branch
circuits should not exceed 5 per cent over all.

210-7. Grounding Receptacles. Receptacles and cord connectors

equipped with grounding contacts shall have those contacts
effectively grounded. The branch circuit or branch circuit
raceway shall include or provide a grounding conductor to which
the grounding contacts of the receptacle or cord connector shall
be connected. The armor of type AC metal-clad cable, the sheath
of MI and ALS cables, or a metallic raceway is acceptable as a
grounding conductor. See Sections 210-21(b), 250-45, 250-57(a),
250-59 and 350-5.

Exception: For extensions only in existing installations

which do not have a grounding conductor in the branch circuit, the
grounding conductor of a grounding type receptacle outlet may be
grounded to a grounded cold water pipe near the equipment.

210-8. Heavy-Duty Lampholders. Heavy-duty lampholders referred

to in this Article shall include lampholders rated at not less
than 750 watts.

Exception: Admedium lampholders rated at 660 watts shall be

considered to be heavy duty type.
B. Specific Requirements

210-19. Conductors. Circuit conductors shall conform to the

following:

(a) Ampacity. Shall have an ampacity of not less than the

rating of the branch circuit and not less than the maximum load to
be served.

(b) Minimum Size. Shall not be smaller than No. 8 for ranges
of 8-3/4 kw or more rating, nor smaller than No. 14 for other
loads.
(c) Exceptions:

Exception No. 1. Range Loads. See Note 5 of Table 220-5.

Where the maximum demand of a range of 8-3/4 kw or more rating is
computed according to Column A of Table 220-5, the neutral
conductor of a three-wire branch circuit supplying a household
electric range, a wall mounted oven or a counter-mounted cooking
unit may be smaller than the ungrounded conductors but shall have
an ampacity at least 70 per cent of the ampacity of the ungrounded
conductors and shall not be smaller than No. 10.

Cable assemblies with the neutral conductor smaller than the

ungrounded conductors shall be so marked.
 Exception No. 2. Tap Conductors. Tap conductors may be of
less capacity than the branch circuit rating provided no tap
conductor is of less capacity than the load to be served and
provided the rating is not less than 20 amperes for 40 or 50
ampere circuits or 15 amperes for circuits rated less than 40
amperes and only when these tap conductors supply either:

(a) Individual lampholders or fixtures with taps extending

not longer than 18 inches beyond any portion of the lampholder or
fixture, except as required in Section 410-65 (b-2); or,

(b) Individual outlets with taps not over 18 inches long; or,

(c) Infra-red lamp industrial heating appliances.

(d) Nonheating leads of snow and ice melting cables and mats.

Exception No. 3. Fixture Wires and Cords. Fixture wires and

cords may be of smaller size, but not less than the size specified
in Exception No. 3 of Section 240-5(a).

See Tables 400-9(b) and 402-4.

Exception No. 4. Outlet Devices. Outlet devices may have

less carrying capacity than the branch circuit rating, but not
less than the types and ratings specified in Sections 210-21(a-c).

Exception No. 5. Where tap conductors supply electric

ranges, wall-mounted electric ovens and counter-mounted electric
cooking units from 50 ampere branch circuits they shall be of
suitable capacity for the load to be served, not less than 20
amperes in rating and no longer than necessary for servicing the
appliance.

210-20. Overcurrent Protection. The rating or setting of

overcurrent devices shall conform to the following:

(a) Rating. Shall not be in excess of the value specified in

Section 240-5.

Exception: Tap Conductors and Fixture Wires. Tap

conductors, fixture wire and cords as permitted in Section 210-
19(c) may be considered as protected by the circuit overcurrent
device.

(b) Single Appliance. Shall not exceed 150 per cent of the
rating of the appliance, where the circuit supplies only a single
appliance of 10-ampere or more rating.

(c) Continuous Loads. Where loads other than motor loads

will constitute continuous loads see Sections 210-23(b), 220-2 &
240-2.
210-21. Outlet Devices. Outlet devices shall have a rating not
less than the load to be served and shall conform to the
following:

(a) Lampholders. Lampholders when connected to circuits

having a rating of over 20 amperes shall be of the heavy-duty
type.

(b) Receptacles. Receptacles installed on 15 ampere and 20

ampere branch-circuits shall be of the grounding type and they
shall be installed in accordance with Section 210-7. Grounding
type receptacles which are of a type that rejects non-grounding
type attachment plugs or which are of the locking type may be used
for specific purposes or in special locations.

A single receptacle installed on an individual branch circuit

shall have a rating of not less than the rating of the branch
circuit.

When grounding type receptacles are used as replacements for

existing non-grounding types of grounding conductor installed in
accordance with Section 250-57 shall be provided. If it is
impractical to reach a source of ground a non-grounding type
receptacle shall be used. The installation of grounding type
outlets shall not be used as a requirement that all portable
equipment be of the grounded type. See Article 250 for
requirements for the grounding of portables.

Receptacles required in Section 517-3(d) are considered as

meeting the requirements of this Section.

When connected to circuits having two or more outlets,

receptacles shall conform to the following:

15-amp. circuits ..................... Not over 15-amp.

rating
20-amp. circuits ..................... 15 or 20-amp. rating
30-amp. circuits ..................... 30-amp. rating
40-amp. circuits ..................... 40 or 50-amp. rating
50-amp. circuits ..................... 50-amp. rating

Receptacles connected to circuits having different voltages,

frequencies or types of current (AC or DC) on the same premises
shall be of such design that attachment plugs used on such
circuits are not interchangeable.

Grounding type receptacles shall be installed only on

circuits of the voltage class and current for which they have been
approved.

Receptacles rated at 15 amperes connected to 15 or 20 ampere

branch circuits serving two or more outlets shall not supply a
total load in excess of 12 amperes for portable appliances.
Receptacles rated at 20 amperes connected to 20 ampere branch
circuits serving two or more outlets shall not supply a total load
in excess of 16 amperes for portable appliances.

(c) Capacity of range receptacles may be based on single

range loads as computed from Table 220-5.

210-22. Receptacle Outlets Required. Receptacle outlets shall be

installed as follows:

(a) General. Where portable cords are used, except where the
attachment of cords by other means is specifically permitted.

A cord connector that is supported by a permanently connected

cord pendant is considered a receptacle outlet.

(b) Dwelling Type Occupancies. In every kitchen, family

room, dining room, breakfast room, living room, parlor, library,
den, sun room, recreation room and bedroom, receptacle outlets
shall be installed so that no point along the floor line in any
wall space is more than six feet, measured horizontally, from an
outlet in that space including any wall space two feet wide or
greater and the wall space occupied by sliding panels in exterior
walls. The receptacle outlets shall, insofar as practicable, be
spaced equal distances apart. Receptacle outlets in floor shall
not be counted as part of the required number of receptacle
outlets unless located close to the wall. At least one outlet
shall be installed for the laundry.

Outlets in other sections of the dwelling for special

appliances such as laundry equipment, shall be placed within 6
feet of the intended location of the appliance.

Exception No. 1. A dwelling unit that is an apartment or

living area in a multi-family building where laundry facilities
are provided on the premises that are available to all building
occupants need not be provided with a laundry receptacle.

Exception No. 2. In other than single family dwellings where

laundry facilities are not to be installed or permitted, a laundry
receptacle need not be provided.

Exception No. 3. A dwelling that is a unit in a hotel,

motel, motor court, or motor hotel, need not be provided with a
laundry receptacle.
(c) Guest rooms in Hotels, Motels, and Similar Occupancies.
These shall have receptacles installed in accordance with Section
210-22(b).

210-23. Maximum Load. The maximum load shall conform to the

following:
 (a) Appliances Consisting of Motors and Other Loads. Where a
circuit supplies only motor operated appliance loads, Article 430
shall apply. For other than a portable appliance, the branch
circuit size shall be calculated on the basis of 125 per cent of
motor load where the motor is larger than 1/8 hp plus the sum of
the other loads.

(b) Other Loads. The total load shall not exceed the branch
circuit rating, and shall not exceed 80 per cent of the rating
when load will constitute a continuous load such as store lighting
and similar loads. In computing the load of lighting units which
employ ballasts, transformers or auto-transformers, the load shall
be based on the total of the ampere rating of such units and not
on the wattage of the lamps.

Exception No. 1. When the assembly including the overcurrent

device protecting the branch circuit is approved for continuous
operation at 100 per cent of its rating, the total load may equal
the branch circuit rating.

Exception No. 2. Where branch circuits are derated in

accordance with Note 8 of Tables 310-12 through 310-15 the
derating factor for continuous loading shall not apply.

Exception No. 3. Range Loads. See Note 5 of Table 220-5.

210-24. Permissible Loads. Individual branch circuits may supply

any loads.

Branch circuits having two or more outlets may supply only

loads as follows:

(a) 15- and 20-Ampere Branch Circuits. Lighting units and/or

appliances. The rating of any one portable appliance shall not
exceed 80 per cent of the branch circuit rating. The total rating
of fixed appliances shall not exceed 50 per cent of the branch
circuit rating when lighting units or portable appliances are also
supplied. Small appliance branch circuits shall supply only the
loads stipulated in Section 220-3(b).

(b) 30-Ampere Branch Circuits. Fixed lighting units with

heavy duty lampholders in other than dwelling occupancies; or
appliances in any occupancy. The rating of any one portable
appliance shall not exceed 24 amperes.

(c) 40-Ampere Branch Circuits. Fixed lighting units with

heavy duty lampholders in other than dwelling occupancies; or
fixed cooking appliances; or infra-red heating units.

(d) 50-Ampere Branch Circuits. Fixed lighting units with

heavy duty lampholders in other than dwelling occupancies; or
fixed cooking appliances; or infra-red heating units.
 The term "fixed" as used in this Section recognizes cord
connections where otherwise permitted.

Fixed outdoor electric snow melting and deicing installations

may be supplied by any of the branch circuits described herein
provided the circuit supplies no other load.

210-25. Table of Requirements. The requirements for circuits

having two or more outlets [other than the receptacle circuits of
Section 220-3(b)] as specifically provided for above are
summarized in Table 210-25.
Table 210-25
Branch Circuit Requirements

(Type FEP, FEPB, RUW, SA, T, TW, RH, RUH, RHW, RHH, THHN, THW,
THWN, and XHHW conductors in raceway or cable.)
─────────────────────────────────────────────────────────────────
CIRCUIT RATING 15 Amp. 20 Amp. 30 Amp. 40 Amp. 50 Amp.
─────────────────────────────────────────────────────────────────
CONDUCTORS:
(Min. Size)
Circuit Wires* 14 12 10 8 6
Taps 14 14 14 12 12
Fixture Wires
and Cords Refer to Section 240-5(a), Exception No. 3
─────────────────────────────────────────────────────────────────
OVERCURRENT
PROTECTION 15 Amp. 20 Amp. 30 Amp. 40 Amp. 50 Amp.
─────────────────────────────────────────────────────────────────
Lampholders Any Any Heavy Heavy Heavy
Permitted Type Type Duty Duty Duty
Receptacle 15 Max. 15 or 20 30 40 or 50 50
Rating Amp. Amp. Amp. Amp. Amp.
─────────────────────────────────────────────────────────────────
MAXIMUM
LOAD 15 Amp. 20 Amp. 30 Amp. 40 Amp. 50 Amp.
─────────────────────────────────────────────────────────────────
PERMISSIBLE Refer to Refer to Refer to Refer to Refer to
LOAD Section Section Section Section Section
210-24(a) 210-24(a) 210-24(b) 210-24(c) 210-
24(d)
─────────────────────────────────────────────────────────────────
*These ampacities are for copper conductors where derating is not
required. See Tables 310-12 through 310-15.