How does the 2023 NEC simplify electric vehicle (EV) branch circuit requirements?

625.40 Electric Vehicle Branch Circuit 

Overview 

Electric Vehicle Supply Equipment (EVSE) is essential for providing efficient and reliable charging for electric vehicles. EVSEs can vary in power requirements, ranging from standard 120-volt outlets to high-voltage 480-volt chargers. Previously, NEC Section 625.40 required each EVSE to have its own individual branch circuit, which often resulted in underutilized circuits, especially for lower-power Level 1 chargers. The 2023 NEC update addresses this issue by mandating individual branch circuits only for EVSEs that exceed 16 amperes or 120 volts. This change allows multiple EVSEs to share a single branch circuit where appropriate.

Applying the 2023 Code 

Electric Vehicle Supply Equipment (EVSE) encompasses various charging levels designed to meet different needs. Level 1 charging, the slowest method, uses a standard 120-volt outlet and is typically used in residential settings. Level 2 charging, which requires 208 to 240 volts, is commonly found in public places such as parking garages and commercial locations. Level 3 charging, the fastest method, operates at 480 volts or more and is usually installed at commercial or industrial charging stations. Each level presents distinct design requirements for branch circuits: Level 1 circuits are generally less demanding, while Levels 2 and 3 require circuits capable of handling higher voltages and currents. 

In previous NEC versions, Section 625.40 mandated that all EVSEs be supplied by individual branch circuits, regardless of their size or level. This led to inefficiencies, particularly with Level 1 chargers that could utilize standard 120-volt outlets. To rectify this, the 2023 NEC version revised Section 625.40. The updated code now requires individual branch circuits only for EVSE outlets exceeding 16 amperes or 120 volts. Additionally, a new exception allows for branch circuits to serve multiple EVSEs, as outlined in Section 625.42(A) or (B). This change optimizes circuit usage and reduces unnecessary wiring, improving efficiency in residential and commercial EVSE installations. 

What’s New for the 2023 NEC? 

The table below presents a comparison between the 2020 NEC and the 2023 NEC regarding Section 625.40.