EV Charger Load Calculator for North Carolina
NEC 2017 ev charger load math for EV charger installers working in North Carolina.
Sizing an EV charger circuit in North Carolina starts with NEC 2017 Article 625 — the EVSE branch must be sized to 125% of the continuous load. Hot-climate warm-band states like North Carolina (92°F design ambient) also force a 0.88× ampacity correction at 75°C terminations.
Worked example for North Carolina
For a 48 A Level 2 charger on a 240 V single-phase circuit, the OCPD is sized to 60 A (48 × 1.25 = 60.0 A, rounded up to the next standard breaker). The conductor must carry 60 A after North Carolina's 0.88× correction — that typically lands at #6 AWG copper THWN-2 for a residential garage run, with conduit fill checked separately if you're stacking multiple home runs.
Code & Utilities
EV installations in North Carolina are governed by the 2017 National Electrical Code, in force since 2018. That includes Article 625 EVSE rules and the 125% continuous-load factor on charging branch circuits, though some 2020-cycle changes (like expanded EMS provisions) are not yet enforced statewide.
Major electric utilities serving North Carolina include Duke Energy Carolinas, Duke Energy Progress, Dominion Energy NC. Each has its own service-upgrade timeline, EV rebate availability, and metering rules — confirm them before quoting commercial work.
Climate & Ampacity
Plan EV feeders against a 92°F ambient in North Carolina — the resulting NEC 310.15(B) correction of 0.88× is what trims a #6 THWN-2 down to its true continuous rating. Because the correction is below 0.9, conductors that "look fine" on a 30°C ampacity table will not carry their nameplate current here — always derate explicitly.
North Carolina takeaway
Always cross-check the EVSE manufacturer's listed maximum overcurrent rating; Duke Energy Carolinas may also have specific service-upgrade or load-management requirements you'll need to coordinate before final inspection.