The general rule of thumb is that higher charging power translates to a shorter charging time. How fast the vehicle can be charged will be affected by several factors. The limitation on the charging effect will therefore be governed by the weakest of the following factors:
Main power grid
The voltage on the power supply to the house will determine how fast you can charge the vehicle. We distinguish between 400V (TN) and 230V (IT), as well as the number of phases that are set up, 1-phase or 3-phase.
In Norway, IT is still the most widespread grid type. The fastest charging effect on an IT 3-phase installation is 11kW.
The circuit breaker
The capacity of the circuit breaker determines how much load can be carried through the fuse box and up to the charging station. The rating of the circuit breaker will be adapted to your electrical installation and determines how much power will be available for charging. If the fuse has a lower rating than what the charging station supports (32A 1-phase / 3-phase), it will limit the maximum charging capacity.
The capacity of the charging cable may limit the charging speed if the current rating is lower than the other factors mentioned in this list. There are different versions, ranging from 16A 1-phase up to 32A 3-phase.
On-Board Charger (OBC)
The efficiency and size of the On-Board Charger has the final say on how fast the vehicle can charge. The most common sizes of On-Board Chargers range between 3.3kW and 22kW. The charging cable connects to the on-board charger which then converts the energy to fit the vehicle battery.
There are additional factors that may impact the charging effect.
Low temperatures, battery health and energy loss during charging.
In order to achieve the highest possible charging power the following factors need to be in place: power grid, charging station, charging cable and a vehicle that supports 3-phase charging. If one of these factors are missing, charging will always be 1-phase.
Zaptec charging stations support charging on IT installations and TN installations, 32A both on 1-phase and 3-phase.