625
Electric Vehicle Charging Systems
Every EV charger installation must comply with Article 625 whether it is a simple 120-volt Level 1 cord-and-plug unit or a hardwired 240-volt Level 2 station in a commercial garage. The article establishes several critical rules. First, Section 625.40 requires an individual branch circuit for any EVSE outlet rated above 16 amps or 120 volts — you cannot share that circuit with other loads. A branch circuit is permitted to supply multiple EVSEs only when managed by an energy management system per 625.42(A) or (B). Second, EV charging loads are treated as continuous loads, meaning the branch circuit and its overcurrent device must be rated at 125 percent of the maximum load. So a 40-amp EVSE needs a 50-amp breaker and conductors rated for at least 50 amps. Third, all receptacles installed for the connection of EV charging must have GFCI protection per 625.54 — this applies to all single-phase and three-phase receptacle configurations specified in 625.44(A) and (B). Hardwired (direct-connected) EVSE does not use a receptacle and is not subject to 625.54 unless the manufacturer's instructions require GFCI protection. Fourth, a disconnecting means must be installed for the EVSE and must be lockable in accordance with 110.25. For cord-and-plug connected units, the plug and receptacle can serve as the disconnect. For hardwired units, a separate lockable disconnect must be readily accessible — if installed remote from the EVSE, a plaque must identify its location. The 2023 NEC made significant updates including recognizing energy management systems that allow multiple EVSEs to share a feeder or branch circuit by dynamically managing the load, which is a game changer for multi-unit parking structures and commercial installations.
When You Need This
- Installing a Level 2 (240V) EV charger in a residential garage — need to size the dedicated circuit at 125% of the charger rating
- Designing EV charging infrastructure for a commercial parking garage with multiple stations sharing a feeder through energy management
- Adding an EV charger to an existing residential panel and need to verify the service has enough capacity
- Determining whether a cord-and-plug installation or hardwired installation is appropriate for a particular EVSE
- Answering exam questions about EV charging — Article 625 is increasingly appearing on journeyman and master exams
Key Points
Common Mistakes
Sizing the circuit at 100% of the EVSE load instead of 125% — EV charging is a continuous load and must be derated accordingly
Sharing a branch circuit between an EVSE and other loads like a garage door opener or lighting — 625.40 requires a dedicated circuit for units over 16A or 120V
Omitting GFCI protection on a cord-and-plug EVSE receptacle because the charger has built-in ground fault detection — 625.54 requires GFCI at the receptacle for cord-and-plug installations regardless of the charger's internal protection
Installing a non-listed (uncertified) EV charger purchased online — all EVSE must be listed per 625.44
Forgetting the disconnecting means for a hardwired charger — a separate lockable disconnect must be readily accessible per 625.43
Exam Tip
The key exam concept is continuous load treatment. If a question says a 40-amp EVSE is being installed, the branch circuit must be rated for 40 x 1.25 = 50 amps. That means a 50-amp breaker and conductors with at least 50-amp ampacity from Table 310.16. Also remember that under the 2023 NEC, GFCI protection per 625.54 is mandatory for all receptacles installed for EV charging — this is a common trick question.
Frequently Asked Questions
While physically possible with an adapter, it is not code-compliant if the circuit is shared with a dryer. Section 625.40 requires an individual branch circuit for EVSE rated over 16A or 120V. You would need a dedicated circuit, and the receptacle must have GFCI protection per 625.54.
A cord-and-plug EVSE connects to a receptacle (like a NEMA 14-50) and can be unplugged and moved. A hardwired EVSE is permanently wired to the branch circuit and requires a separate disconnecting means. Both are treated as continuous loads at 125%, but the disconnect requirements differ — the plug serves as the disconnect for cord-and-plug units.
Yes, under the 2023 NEC, Section 625.42(A) and (B) permits multiple EVSEs on a single branch circuit or feeder when controlled by a listed energy management system (EMS) that ensures the total load never exceeds the circuit rating. This is a major cost savings for multi-unit installations.
Related Code Sections
This is an educational summary, not the official code text. The NEC® is a registered trademark and copyright © National Fire Protection Association (NFPA). The CEC is copyright © CSA Group. For official code text, visit nfpa.org or csagroup.org. SparkShift is not affiliated with NFPA or CSA Group.