NEC 1999 National Electrical Code
Article 625 - Electric Vehicle Charging System
A. General
625-1. Scope. The provisions of this article cover the elec-
trical conductors and equipment external to an electric vehi-
cle that connect an electric vehicle to a supply of electricity
by conductive or inductive means, and the installation of
equipment and devices related to electric vehicle charging.
FPN: for industrial trucks, see Fire Safety Standard for
Powered Industrial Trucks Including Type Designations,
Areas of Use, Conversions, Maintenance, and Operation.
NFPA 505-1996
625-2. Definitions
Electric Vehicle. An automotive-type vehicle for high-
way use, such as passenger automobiles, buses, trucks, vans,
and the like, primarily powered by an electric motor that
draws current from a rechargeable storage battery, fuel cell,
photovoltaic array, or other source of electric current. For
the purpose of this article, electric motorcycles and similar
type vehicles and off-road self-propelled electric vehicles,
such as industrial trucks, hoists, lifts, transports, golf carts,
airline ground support equipment, tractors, boats, and the
like, are not included.
Electric Vehicle Connector. A device that by insertion
into an electric vehicle inlet, establishes an electrical connec-
tion to the electric vehicle for the purpose of charging and
information exchange. This is part of the electric vehicle
coupler.
Electric Vehicle Coupler. A mating electric vehicle inlet
and electric vehicle connector set.
Electric Vehicle Inlet. The device on the electric vehicle
into which the electric vehicle connector is inserted for
charging and information exchange. This is part of the elec-
tric vehicle coupler. For the purposes of this Code the elec-
tric vehicle inlet is considered to be part of the electric
vehicle and not part of the electric vehicle supply equipment.
Electric Vehicle Nonvented Storage Battery. A her-
metically-sealed battery comprised of one or more recharge-
able electrochemical cells that has no provision for release
of excessive gas pressure, or the addition of water or electro-
lyte, or for external measurements of electrolyte specific
gravity.
Electric Vehicle Supply Equipment. The conductors,
including the ungrounded, grounded, and equipment ground-
ing conductors and the electric vehicle connectors. attach-
ment plugs, and all other fittings, devices, power outlets, or
apparatuses installed specifically for the purpose of deliver-
ing energy from the premises wiring to the electric vehicle.
Personnel Protection System. A system of personnel
protection devices and constructional features that when
used together provide protection against electric shock of
personnel.
625-3. Other Articles. Whenever the requirements of other
articles of this Code and Article 625 differ, the requirements
of Article 625 shall apply.
625-4. Voltages. Unless other voltages are specified. the
nominal ac system voltages of 120, 120/240, 208Y/120, 240,
480Y/277, 480, 600Y/347, and 600 volts shall be used to
supply equipment covered by this article.
625-5. Listed or Labeled. All electrical materials, devices.
fittings, and associated equipment shall be listed or labeled.
B. Wiring Methods
625-9. Electric Vehicle Coupler. The electric vehicle cou-
pler shall comply with (a) through (f).
(a) Polarization. The electric vehicle coupler shall be pol-
larized unless part of a system identified and listed as suitable
for the purpose.
(b) Noninterchangeability. The electric vehicle coupler
shall have a configuration that is noninterchangeable with
wiring devices in other electrical systems. Nongrounding-
type electric vehicle couplers shall not be interchangeable
with grounding-type electric vehicle couplers.
(c) Construction and Installation The electric vehicle
coupler shall be constructed and installed so as to guard
against inadvertent contact by persons with parts made live
from the electric vehicle supply equipment or the electric
vehicle battery.
(d) Unintentional Disconnection. The electric vehicle
coupler shall be provided with a positive means to prevent
unintentional disconnection.
(e) Grounding Pole. The electric vehicle coupler shall be
provided with a grounding pole, unless part of a system
identified and listed as suitable for the purpose in accordance
with Article 250.
(f) Grounding Pole Requirements. If a grounding pole is
provided, the electric vehicle coupler shall be designed so
that the grounding pole connection is the first to make and
the last to break contact.
C. Equipment Construction
625-13. Electric Vehicle Supply Equipment. Electric vehicle
supply equipment rated at 125 volt, single phase, 15
or 20 amperes or part of a system identified and listed as
suitable for the purpose and meeting the requirements of
Sections 625-18. 625-19. and 625-29 shall be permitted to
be cord and plug connected. All other electric vehicle supply
equipment shall be permanently connected and fastened in
place. This equipment shall have no exposed live parts.
625-14. Rating. Electric vehicle supply equipment shall
have sufficient railing to supply the load served. For the
purposes of this article. electric vehicle charging loads shall
be considered to be continuous loads.
625-15. Markings. The electric vehicle supply equipment
shall comply with (a) through (c).
(a) General. All electric vehicle supply equipment shall be
marked by the manufacturer
FOR USE WITH ELECTRIC VEHICLES
(b) Ventilation Not Required. where marking is required
by Section 625-29(c), the electric vehicle supply equipment
shall be clearly marked by the manufacturer
VENTILATION NOT REQUIRED
The marking shall be located so as to be clearly visible
after installation.
(c) Ventilation Required. Where marking is required by
Section 625-29(d), the electric vehicle supply equipment
shall be clearly marked by the manufacturer "Ventilation
Required." The marking shall be located so as to be clearly
visible after installation.
625-16. Means of Coupling. The means of coupling to the
electric vehicle shall be either conductive or inductive.
Attachment plugs, electric vehicle connectors, and electric
vehicle inlets shall be listed or labeled for the purpose.
625-17. Cable. The electric vehicle supply equipment
cable shall be Type EV, EVJ, EVE, EVJE. EVT, or EVJT
flexible cable as specified in Article 400 and Table 400-4.
Ampacities shall be as specified in Table 400-5(A) for No.
10 and smaller and Table 400-5(8) for No. 8 and larger.
The overall length of the cable shall not exceed 25 ft (7.63m).
Other cable types and assemblies listed as being suitable
the purpose, including optional hybrid communications,
signal, and optical fiber cables, shall be permitted.
625-18. Interlock. Electric vehicle supply equipment shall
be provided with an interlock that de-energizes the electric
vehicle connector and its cable whenever the electric connec-
tor is uncoupled from the electric vehicle. An interlock shall
not be required for portable cord- and plug connected elec-
tric vehicle supply equipment intended for connection to
receptacle outlets rated 125 volts, single phase, 15 and 20
amperes.
625-19. Automatic De-energization of Cable. The elec-
tric vehicle supply equipment or the cable connector combi-
nation of the equipment shall be provided with an automatic
means to de-energize the cable conductors and electric vehi-
cle connector upon exposure to strain that could result in
either cable rupture or separation of the cable from the
electric connector and exposure of live parts. Automatic
means to de-energize the cable conductors and electric vehi-
cle connector shall not be required for portable cord- and
plug-connected electric vehicle supply equipment intended
for connection to receptacle outlets rated at 115 volts, single
phase, 15 and 20 amperes.
D. Control and Protection
625-21. Overcurrent Protection. Overcurrent protection
for feeders and branch circuits supplying electric vehicle
supply equipment shall be sized for continuous duty and
shall have a rating of not less than 125 percent of the maxi-
mum load of the electric vehicle supply equipment. Where
noncontinuous loads are supplied from the same feeder or
branch circuit, the overcurrent device shall have a rating of
not less than the sum of the noncontinuous loads plus 125
percent of the continuous loads.
625-22. Personnel Protection System. The electric vehi-
cle supply equipment shall have a listed system of protection
against electric shock of personnel. The personnel protec-
tion system shall be composed of listed personnel protection
devices and constructional features. Where cord- and plug-
connected electric vehicle supply equipment is used, the
interrupting device of a listed personnel protection system
shall be provided and shall be an integral part of the attach-
ment plug or shall be located in the power supply cable not
more than 12 in. (305 mm) from the attachment plug.
625-23. Disconnecting Means. For electric vehicle supply
equipment rated more than 60 amperes or more than 150
volts to ground, the disconnecting means shall be provided
and installed in a readily accessible location. The discon-
necting means shall be capable of being locked in the open
position.
625-25. Loss of Primary Source. Means shall be provided
such that upon loss of voltage from the utility or other
electric system(s), energy cannot be backfed through the
electric vehicle supply equipment to the premises wiring
system. The electric vehicle shall not be permitted to serve
as a standby power supply.
E. Electric Vehicle Supply Equipment Locations
625-28. Hazardous (Classified) Locations. Where elec-
tric vehicle supply equipment or wiring is installed in a
hazardous (classified) location, the requirements of Articles
500 through 516 shall apply.
625-29. Indoor Sites. Indoor sites shall include, but not
be limited to, integral, attached, and detached residential
garages; enclosed and underground parking structures; repair
and nonrepair commercial garages; and agricultural build-
ings.
(a) Location. The electric vehicle supply equipment shall
be located to permit direct connection to the electric vehicle.
(b) Height. Unless specifically listed for the purpose and
location, the coupling means of the electric vehicle supply
equipment shall be stored or located at a height of not less
than 18 in. (457 mm) and not more than 4 ft (1.22 m) above
the floor level.
(c) Ventilation Not Required. Where electric vehicle non-
vented storage batteries are used or where the electric vehicle
supply equipment is listed or labeled as suitable for charging
electric vehicles indoors without ventilation and marked in
accordance with Section 615-15(b), mechanical ventilation
shall not be required.
(d) Ventilation Required. Where the electric vehicle sup-
ply equipment is listed or labeled as suitable for charging
electric vehicles that require ventilation for indoor charging
and marked in accordance with Section 625-15(c), mechan-
cal ventilation, such as a fan, shall be provided. The ventila-
lion shall include both supply and exhaust equipment and
shall be permanently installed and located to intake from,
and sent directly to, the outdoors. Positive pressure ventila-
tion systems shall only be permitted in buildings or areas
that have been specifically designed and approved for that
application. Mechanical ventilation requirements shall be
determined by one of the following methods.
(1) For supply voltages and currents specified in Table
625-29(d), the minimum ventilation requirements in cubic
feet per minute (cfm) shall be as specified in Table 625-
29(d) for each of the total number of electric vehicles that
can be charged at one time. This table allows for sufficient
ventilation for any configuration of electric vehicle supply
equipment and electric vehicle charging space.
(2) For supply voltages and currents other than specified
in Table 625-29(d), the minimum ventilation requirements
in cubic feet per minute (cfm) shall be calculated by means
of the following general formulas as applicable.
(a) Single phase:
Ventilation = (volts)(amperes)/48.7
(b) Three phase:
Ventilation = 1.732 (volts)(amperes)/48.7
(3) For an electric vehicle supply equipment ventilation
system designed by a person qualified to perform such cal-
culations as an integral part of a building's total ventilation
system, the minimum ventilation requirements shall be per-
mitted to be determined per calculations specified in the
engineering study.
The supply circuit to the mechanical ventilation equip-
ment shall be electrically interlocked with the electric vehicle
supply equipment and shall remain energized during the
entire electric vehicle charging cycle. Electric vehicle supply
equipment shall be marked in accordance with Section 625-15.
Electric vehicle supply equipment receptacles rated at
125 volts, single phase, 15 and 20 amperes shall be marked
in accordance with Section 625-15(c) and shall be switched
and the mechanical ventilation system shall be electrically
interlocked through the switch supply power to the recepta-
cle.
For receptacles at each electric vehicle charging space
identified "For Use with Electric Vehicles." and rated 125
volts, single phase, 15 and 20 amperes, such receptacles shall
be switched, and mechanical ventilation shall be electrically
interlocked through the switch supply power to the recepta-
cle.
625-30. Outdoor Sites. Outdoor sites shall include, but not
be limited to, residential carports and driveways, curbside,
open parking structures, parking lots, and commercial charg-
ing facilities.
(a) Location. The electric vehicle supply equipment shall
be located to permit direct connection to the electric vehicle.
(b) Height. Unless specifically listed for the purpose and
location, the coupling means of electric vehicle supply equip-
ment shall be stored or located at a height of not less than
24 in. (610 mm) and not more than 4 ft (1.22 m) above the
parking surface.
_________________________________________________________
Table 625-29(d), Minimum Ventilation Required in Cubic
Feet per Minute (cfm) for Each of the Total Number of
Electric Vehicles that Can Be Charged at One Time
Branch-Circuit Voltage
Single Phase 3 Phase
_____________________ ____________________________
Branch- 240 V 208 V 480 V 600 V
Circuit or or or or
Ampere 120/ 208 Y/ 480 Y/ 600 Y/
Rating 120 V 208 V 240 V 120 V 240 V 277 V 347 V
15 37 64 74 - - - -
20 49 85 99 148 171 342 427
30 74 128 148 222 236 512 641
40 99 171 197 296 342 683 854
50 123 214 246 370 427 854 1066
60 148 256 296 444 512 1025 1281
100 246 427 493 740 854 1708 2135
150 - - - 1110 1281 2562 3203
200 - - - 1480 1708 3416 4270
250 - - - 1850 2135 4270 5338
300 - - - 2221 2562 5125 6406
350 - - - 2591 2989 3979 7473
400 - - - 2961 3416 6832 8541
______________________________________________________________
m.t.thompson@ieee.org
[madkatz]