Voltage Drop Calculator for Virginia
NEC 2020 voltage drop math for EV charger installers working in Virginia.
Virginia EV installs frequently push past 100 ft of conductor — detached garages, parking-lot DCFC pedestals, and multifamily carport runs all add distance. NEC 2020 recommends a 3% branch / 5% total voltage-drop ceiling.
Worked example for Virginia
A 40 A Level 2 charger at 320 ft on 240 V single-phase #6 Cu shows roughly 5.2% drop. That's above the 3% NEC recommendation, so you'd upsize to #4 or #2 AWG to land back under 3%. Virginia's 0.88× ampacity correction is independent of voltage drop but applies on the same conductor pick.
Code & Utilities
The applicable code in Virginia is the NEC 2020, which the state adopted in 2021. That includes Article 625 (Electric Vehicle Power Transfer System) requirements: 125% continuous-load sizing on EVSE branch circuits, GFCI protection at outdoor receptacles, and provisions for energy management systems on shared circuits.
In Virginia, you'll most often interconnect with Dominion Energy Virginia, Appalachian Power, Old Dominion Electric Cooperative. Their make-ready, time-of-use, and demand-charge structures vary widely; pull the specific tariff before sizing service equipment.
Climate & Ampacity
Plan EV feeders against a 92°F ambient in Virginia — 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.
Virginia takeaway
Voltage drop is a recommendation, not a hard NEC rule — but EVSEs throttle aggressively below ~228 V on a 240 V circuit, so customers in Virginia will notice any drop above 5%.