Charging guide: What charging power can I get?

Faster charging is one of many reasons to invest in a charging station at home. Many people wonder what charging effect (charging speed) they can get when they choose to install a charging box. There are many factors that influence this and we have summarized them in 4 main categories divided into 5 factors in the illustration below:

Charging power will be limited by the weakest link of the 5 factors below.

Online System

Power Course (Installation)

Whether the current course is 1- or 3-phase will determine how much power (kW) you can potentially get. We generally recommend that a 3-phase installation be set up as far as possible. It gives the option of charging with 3-phase, and this gives increased flexibility and potentially more effect when charging as long as there is not a limiting factor in one of the other links.

Charging Station (Installation)

Likewise, the charging station must support 3-phase in order not to be a limiting factor. For example, you will not get more effect with a 3-phase course if the charging station only supports 1-phase, and vice versa. Nevertheless, a charging station that supports 3-phase will be universal as it supports both 1- and 3-phase connection.

Charging Cable

The capacity of the charging cable can be a factor that limits the effect when charging. For example, a 32A/1-phase charging cable will limit the power to a maximum of 7.4 kW as it only supports 1-phase. It will be a limiting factor if it is used on a charging station/installation that has 3-phase available. In contrast, a 32A/3-phase charging cable will not limit charging as it supports up to 32A and both 1- and 3-phase.

The Vehicle

The car's on-board charger (OBC) ultimately determines how much power you get charged with. Hybrids and older electric cars have an OBC of 16A/1 phase (3.7 kW). Newer vehicles have either 32A/1-phase 230V (7.4 kW), 11 kW (16A/3-phase 400V), or up to 22 kW (32A/3-phase 400V) OBC. However, software is also a factor that affects whether the car can/will charge on the various power grids. For example, the Tesla Model 3 fully supports charging at 230V/3-phase, while the Mercedes B-class receives an error message even though both cars have an on-board charger that produces up to 11kW (16A/3-phase 400V). Most newer cars that support 16A/3-phase 400V are charged with 32A/1-phase (7.4 kW) as the car technically connects 2 16A partial chargers together.

Charging Effect and Charging Cable

Mainly four different maximum effects are delivered on charging cables related to charging electric vehicles:

A common misconception is that a charging cable that supports 11 kW (16A/3-phase 400V) charging cannot deliver 7.4 kW (32A/1-phase 230V). The reason is that the charging cable can conduct a maximum of 16A on each of the phases despite the fact that 32A is available on one phase. Simplistically, one can think that a 3-phase charging cable can conduct a maximum of 16A per "wire" (3 pieces / 3-phase), and even if the charging point can output 32A on one of the three "wires", the charging is limited by the charging cable to 16A / 1-phase which corresponds to 3.7 kW. We have simplified how it works in practice in the illustration below:

The table below shows which amperages and which factors in the charging cable are the limiting factor when charging. In general, it is recommended to choose a 32A / 3-phase cable as the cable does not have a limiting factor related to charging.

Limiting factor(s) in the charging cable are highlighted in red.

If you have any further questions, please do not hesitate to contact us.