NEC Codes for EV Chargers "Continuous Loads"
If you’re installing a Level 2 home EV charger that delivers 48 amps (very common for hardwired units), the National Electrical Code treats this as a continuous load—meaning it’s expected to run for 3 hours or more. Because of that, you don’t size the circuit at 48A—you apply the 125% rule. That brings the minimum circuit size up to 60 amps (48A × 1.25 = 60A). This means your breaker must be rated for 60A, and the entire circuit—from panel to charger—must be designed accordingly. For conductor sizing, most residential installs will require #6 AWG copper (THHN/THWN in conduit or NM-B where permitted) to safely handle a 60A circuit under typical conditions. If you’re using aluminum conductors, you’ll generally step up to #4 AWG aluminum. Always verify ampacity using NEC Table 310.16 and adjust for factors like ambient temperature, conduit fill, or long runs that may introduce voltage drop. Also, per NEC Article 625 (which specifically covers EV charging systems), the charger must be on a dedicated circuit, and many units require a hardwired connection for full 48A output (plug-in models are often limited to 40A max).