Power Calculator Calculator for Idaho
NEC 2020 power calculator math for EV charger installers working in Idaho.
Converting between kW and amps is the entry point for nearly every Idaho EV install spec — manufacturers publish kW, but the panel, breaker, and feeder live in amps.
Worked example for Idaho
A 50 kW EVSE draws roughly 208 A at 240 V single-phase, or 60 A at 480 V three-phase. Apply the NEC 2020 125% continuous-load multiplier before sizing the OCPD or feeder. Idaho Power typically meters DCFC sites at the 480 V three-phase service in Idaho.
Code & Utilities
Idaho currently enforces the NEC 2020 edition, 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.
Idaho's primary EV-relevant utilities are Idaho Power, Avista Utilities, Rocky Mountain Power. 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 96°F ambient in Idaho — the resulting NEC 310.15(B) correction of 0.82× 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.
Idaho takeaway
For three-phase math, always confirm the actual nameplate power factor — DCFC equipment is usually 0.95+ but older site-rated equipment can be lower, which changes the apparent power and the conductor pick.