The Tesla Gen3 Charger is rated to charge at a maximum of 20A per phase (for a total of 60A across three phases), but it may not always charge at that maximum rate. There are a few reasons why the charger may be charging at a lower rate:
# The electrical service at your home may not be able to support the full 60A charge rate. Make sure you have the right electrical service to support the charger.
# The wiring in your home may not be capable of handling the full charge rate. Make sure that the wiring is rated for the full 60A charge rate.
# The Tesla vehicle may be charging at a lower rate to protect its battery from overheating or overcharging.
You can check the charging rate for your Tesla by going to the "Charge" screen on the vehicle's touch screen display. If the charging rate is lower than expected, you can contact Tesla customer support for further assistance.
To forget the old charger and use the new one, you can try disconnecting the car from the old charger, clear the charger settings in the car, and then connect it to the new one and register it.