Most of Article 625 is about the box on the wall. Only a handful of paragraphs are about the cable, and those are the ones that decide what you can actually buy.
That imbalance explains most of the confusion we see in enquiries. A buyer compares two charging cables by conductor size and jacket material and assumes the rest is a commodity. The code does not treat the cable as a commodity. It treats the cable as the part of the system most likely to be abused in the field, and it writes rules aimed squarely at that.
What Article 625 puts on the cable
Article 625 stops at the vehicle
The scope sentence matters more than it looks. 625.1 covers "the electrical conductors and equipment external to an electric vehicle that connect an electric vehicle to a supply of electricity by conductive or inductive means." Two things follow.
First, the vehicle inlet is expressly outside the article. 625.2 says the inlet is considered part of the electric vehicle and not part of the electric vehicle supply equipment. The connector on the car is the car maker’s problem; everything from the supply end up to the connector is the installation’s problem.
Second, the article is written around a system, not a bill of materials. The definition of electric vehicle supply equipment in 625.2 is deliberately wide — the conductors, "including the ungrounded, grounded, and equipment grounding conductors and the electric vehicle connectors, attachment plugs, and all other fittings, devices, power outlets, or apparatus installed specifically for the purpose of transferring energy between the premises wiring and the electric vehicle."
A charging cable is inside that definition. It is not an accessory to the equipment. It is part of the equipment.
The connector end carries its own rule. 625.9(F) requires that where a grounding pole is provided, the coupler must be designed so that "the grounding pole connection is the first to make and the last to break contact." Ground before power, and ground after power. On a connector that gets cycled several times a day for years, that ordering is a mechanical design requirement, not a nicety.
The 25-foot rule
This is the provision most people have never heard of, and the one most likely to make a purchase wrong.
625.17 states that "the overall length of the cable shall not exceed 7.5 m (25 ft) unless equipped with a cable management system that is listed as suitable for the purpose."
The limit is on the cable, measured overall, and it is not a recommendation. The exception is not a longer cable — the exception is a listed cable management system: the reel, the retractor, the counterweighted arm. If you want more than 25 feet, the code’s answer is hardware that manages the cable, and the hardware carries the listing.
For a manufacturer this is clarifying: the long-reach products in this market are not cable problems and cannot be solved by cable improvements. When a customer asks for a 40-foot charging cable with no management system, the honest answer is that the request conflicts with 625.17, not that the conductor is hard to source.
The 25-foot rule and its one exception
Six cable types, and no others
625.17 names the permitted cable: "Type EV, EVJ, EVE, EVJE, EVT, or EVJT flexible cable as specified in Article 400 and Table 400.4."
Six designations, all built on the EV root. Article 400 is the flexible cord and cable article, and Table 400.4 is where each type’s construction is described. The table gives this family two or more conductors plus a grounding conductor or conductors, with optional hybrid data, signal communications and optical fiber, and an insulation of thermoplastic elastomer with optional nylon.
Two footnotes carry most of the technical weight, and both are specific to this family.
Footnote | What it says | What it means when you specify |
|---|
Table 400.4, Note 13 | The stated conductor size applies to nonpower-limited circuits only; power-limited data, signal or communications conductors may extend beyond the stated AWG range | A data pair thinner than the power conductors is permitted |
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Table 400.4, Note 14 | For cables of nylon construction, the insulation thickness is the parenthesised figure | Nylon-jacketed constructions have their own thickness column |
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The section also closes with a genuine opening: "Other cable types and assemblies listed as being suitable for the purpose, including optional hybrid communications, signal, and composite optical fiber cables, shall be permitted." Six types is the default, not a closed list.
What the code will and will not let you change
Note 13 points in two directions at once.
| The freedom | The constraint |
|---|
Applies to | Conductor size of the power-limited data, signal or communications conductors | Every conductor in the assembly |
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The rule | They may extend beyond the stated AWG size range | All conductors shall be insulated for the same cable voltage rating |
|---|
So the freedom is in conductor size, and the thing you cannot vary is the dielectric class. A customer who wants a smaller, cheaper signal pair is asking for something the code allows. A customer who wants a 300-volt signal pair inside a 600-volt power assembly is asking for something it does not. Those two requests look similar on a specification sheet.
Ampacity arrives by cross-reference
625.17 does not give EV cable an ampacity table of its own. It sends you elsewhere: ampacities "shall be as specified in Table 400.5(A)(1) for 10 AWG and smaller, and in Table 400.5(A)(2) for 8 AWG and larger."
The split is at 10 AWG and it is hard — one table below the line, a different table above it. That is the opposite of how most installers are trained to think, where a single table covers the range and footnotes adjust it.
Where EV cable ampacity comes from
One detail here deserves disclosure rather than a confident gloss. Table 400.5(A)(1) sets out its allowable ampacities by type list — a thermoset group, a thermoplastic group, and a group for the small specialty types. Table 400.5(A)(2) carries a title naming the types it covers: SC, SCE, SCT, PPE, G, G-GC and W, with its smallest row at 12 AWG. Neither table’s type list names the EV family by designation.
The EV types get their construction from Table 400.4 and their ampacity through the cross-reference in 625.17. A reader looking for the letters EV inside Table 400.5 will not find them. That is an observation about how the document is organized, drawn from reading the table titles and type lists rather than from any statement in the code, and I am flagging it as such. It does not change what 625.17 requires. It does explain why people who go hunting for an EV ampacity column come away empty-handed.
De-energize on strain, not on fault
625.19 is the provision that shows how the code thinks about this cable. It requires an automatic means to de-energize the cable conductors and 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."
The trigger is mechanical, not electrical. Nothing has to fail electrically for this to operate. The concern is a cable pulled hard enough to tear, or a connector pulled off the end of a cable leaving copper in reach. That is a failure mode created by how people treat a cable in a parking lot, and the answer is to remove the voltage before the damage completes.
The exception is narrow and worth noting for what it excludes: the requirement does not apply to portable cord-and-plug-connected equipment intended for 125-volt, single-phase, 15- and 20-ampere receptacle outlets.
For a cable supplier this is a construction constraint, not only a device constraint. A cable that has to support a strain signal needs a conductor path that survives being stretched to the point where the power conductors are failing. That is exactly the kind of assembly Note 13’s hybrid allowance makes room for.
The protective device that lives in the cable
625.22 requires a listed personnel protection system, then does something unusual with the location. Where the equipment is cord-and-plug connected, the interrupting device "shall be an integral part of the attachment plug or shall be located in the power supply cable not more than 300 mm (12 in.) from the attachment plug."
Two options, both of which put a safety device inside the plug or inside the first foot of the cable. No third option exists.
This is the provision that makes the supply-side cord of a portable unit an engineered part rather than a molded lead. If you are costing a cord set, the enclosure for that interrupting device is in the bill of materials, and its position within 300 mm of the plug is a dimension you have to hold.
Why most charging equipment has no supply cord
625.13 draws a sharp line. Equipment rated at 125 volts, single-phase, 15 or 20 amperes — or forming part of a system listed as suitable and meeting 625.18, 625.19 and 625.29 — may be cord-and-plug connected. Everything else "shall be permanently connected and fastened in place."
That sentence explains a layout that otherwise looks arbitrary. The large wall units have no plug because the code does not let them have one. The hardwired supply is not a cost decision or a market convention; it is what exceeding 125 volts or 15–20 amperes produces.
It also relocates the cable in the system. On a small portable unit the cable in question is the supply cord. On a hardwired unit it is the output cable running to the vehicle, which is where the 25-foot limit applies.
Two further provisions shape the electrical duty.
Provision | Requirement | Effect on sizing |
|---|
625.14 | Charging loads "shall be considered to be continuous loads" | The load is treated as continuous for every downstream calculation |
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625.21 | Overcurrent protection sized for continuous duty, not less than 125 percent of maximum load | A 40-ampere charging load needs a 50-ampere circuit, before any adjustment |
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Where noncontinuous loads share the circuit, 625.21 adds the sum of the noncontinuous loads to 125 percent of the continuous loads.
One location dimension catches people out because it differs indoors and outdoors.
Site | Minimum height | Maximum height | Reference |
|---|
Indoor | 450 mm (18 in.) above floor level | 1.2 m (4 ft) | 625.29 |
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Outdoor | 600 mm (24 in.) above parking surface | 1.2 m (4 ft) | 625.30 |
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FAQ
Does the 25-foot limit include the connector?
625.17 limits the overall length of the cable. The exception is a listed cable management system, not a longer cable.
Can a charging cable carry a data pair thinner than the power conductors?
Yes. Table 400.4, Note 13 permits power-limited data, signal or communications conductors to extend beyond the stated AWG size range — but every conductor in the assembly must be insulated for the same cable voltage rating.
Is EV cable ampacity published in its own table?
No. 625.17 cross-refers to Table 400.5(A)(1) for 10 AWG and smaller and Table 400.5(A)(2) for 8 AWG and larger, and neither table’s type list names the EV family.
Does a hardwired unit need a strain-triggered disconnect?
625.19 applies except to portable cord-and-plug equipment on 125-volt, single-phase, 15- and 20-ampere receptacle outlets.
Charging cable for outdoor and hard-use duty
The code sets the floor. It does not decide what survives a driveway in a wet climate, or a cable dragged across concrete twice a day.
Three things decide that once the code is satisfied: the insulation system and its temperature rating, the jacket’s behavior under abrasion and sunlight, and the strain relief where the assembly leaves the equipment.
If you are specifying an EV charging cable for a program, the useful conversation is about those three things plus the assembly drawing that shows where the interrupting device sits and how the strain signal is routed. Our cable range covers the flexible constructions this application needs, and OEM and ODM projects are where those assembly drawings live.
Sources
- NFPA 70, National Electrical Code, 2011 edition — Article 625 (Electric Vehicle Charging System), sections 625.1, 625.2, 625.9, 625.13, 625.14, 625.17, 625.19, 625.21, 625.22, 625.29 and 625.30. These are the sections the article quotes or cites. Public-domain copy consulted at Internet Archive, gov.law.nfpa.nec.2011.
- Same edition, Article 400 (Flexible Cords and Cables) — Table 400.4 and its Notes 13 and 14; Table 400.5(A)(1) and Table 400.5(A)(2).
