EV Home Charging Time 12kW

Home Charging Time for EVs (up to 12 kW)

Charging at home over AC (Level 2) runs through an EVSE (Electric Vehicle Supply Equipment) wallbox. A single-phase 7.4 kW unit works at 240 V × 32 A. To reach 12 kW you generally need three-phase, either 240 V × ~30 A or a 380 V setup. The math is straightforward: time (h) = (battery × ΔSOC) ÷ power. Take a 60 kWh battery going from 20–100%: roughly 4 h on a 12 kW box, and closer to 6.5 h on a 7.4 kW one.

In Brazil the install has to comply with NBR 17019 and carry INMETRO/ABNT certification. Leave the breaker, the RCD (DR Type B) and the three-phase wiring to a licensed electrician. Brands you'll run into include WEG, Tupinambá, Wallbox Pulsar Plus, ABB Terra AC and Schneider EVlink.

Applications

Use it to schedule overnight charging during off-peak hours (Tarifa Branca), to size your breaker and cable cross-section, or to settle the choice between 7.4 kW single-phase and 11–12 kW three-phase. It also helps when you want a rough energy cost per full charge, or when checking whether a condo's shared circuit can take the wallbox.

FAQ

Do I need three-phase to install a 12 kW wallbox? In most cases, yes. A single-phase install tops out near 7.4 kW (32 A) before you start overloading the residential circuit.

Why doesn’t my car charge at the wallbox’s full rated power? The onboard charger is what decides how much AC the car accepts. Plenty of EVs cap at 7.4 kW even when plugged into an 11 kW box, so it's worth checking the spec sheet.

Is it safe to use a standard outlet? Treat it as emergency "trickle" charging only, at around 2 kW. For anything routine, NBR 17019 requires a dedicated EVSE with proper grounding and an RCD.