Grounding Conductor Calculator for Florida

NEC 2020 grounding conductor math for EV charger installers working in Florida.

EGC sizing in Florida 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 Florida

For a 40 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 Florida's long runs, NEC 250.122(B) requires the EGC to be upsized proportionally.

Code & Utilities

Florida currently enforces the NEC 2020 edition, adopted in 2023. 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.

Florida's primary EV-relevant utilities are Florida Power & Light, Duke Energy Florida, Tampa Electric, Florida Public Utilities. Always verify the applicable tariff and any utility-specific requirements (CT cabinets, metering enclosures, demand limiters) at design time.

Climate & Ampacity

In Florida, the 92°F summer ambient drives a 0.88× 75°C ampacity correction. Bake this into every Level 2 and DCFC conductor pick before you commit to a wire size. 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.

Florida takeaway

On DCFC sites with parallel feeder sets, each parallel raceway needs its own full-size EGC — a detail inspectors in Florida catch frequently on commercial submittals.