Grounding Conductor Calculator for Kentucky
NEC 2020 grounding conductor math for EV charger installers working in Kentucky.
EGC sizing in Kentucky follows NEC 2020 Table 250.122, indexed off the upstream OCPD rating, with parallel rules for parallel sets and increased-conductor adjustments under 250.122(B).
Worked example for Kentucky
For a 50 A EVSE branch, Table 250.122 calls for a minimum #10 Cu equipment grounding conductor. If you upsize the phase conductors for voltage drop in Kentucky's long runs, NEC 250.122(B) requires the EGC to be upsized proportionally.
Code & Utilities
Kentucky currently enforces the NEC 2020 edition, adopted in 2022. 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.
Major electric utilities serving Kentucky include LG&E and KU, Kentucky Power, East Kentucky Power Cooperative. Each has its own service-upgrade timeline, EV rebate availability, and metering rules — confirm them before quoting commercial work.
Climate & Ampacity
Kentucky's representative summer design ambient is around 92°F, which yields a 0.88× ampacity correction factor at 75°C terminations per NEC 310.15(B)(1). 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.
Kentucky takeaway
On DCFC sites with parallel feeder sets, each parallel raceway needs its own full-size EGC — a detail inspectors in Kentucky catch frequently on commercial submittals.