Same issue here. I have a theory. The on-board charger is ultimately rated by kW, not amps.....kW is volts-times-amps. The normal household voltage is 240 and at 48A that would be 11,520 watts. My house shows 245V on the charge screen so I believe the car drops the amps down to 47 to keep the kW in the 11.5 range (245 x 47 = 11,515).