Amperage and EV Charging Speed: What the Numbers Actually Mean
A 48-amp charger adds roughly 30 to 36 miles of range per hour; a 32-amp charger adds roughly 20 to 25. For most drivers, 32 to 40 amps is plenty. Higher amperage only helps if your vehicle's onboard charger can accept it, and many top out around 7.2 kW (about 30 amps) regardless of what your wall unit offers. Circuits are sized at 125% of the charger's continuous draw, so a 48-amp charger needs a 60-amp breaker.