Before you buy an electric vehicle, you will start thinking about home charging. And with it, not only the choice of a charging station, but also the technical preparation for installation. If you are planning a new build, you can prepare it in advance. However, significant obstacles to setting up a powerful station do not have to slow you down even if you decide to install one in an existing family house.
Planning a new build? Factor in a charging station from the start
Building a new family house is always a major challenge. You need to answer a number of questions and come up with solutions you will be happy with for many years. Unfortunately, you often find after completion that you would do some things differently. And this can also apply to mobility questions.
You can prepare your new house for electric car charging in advance. You do not need to invest in a charging station right away if you do not need one at the moment. However, it is important that the electrical installation is prepared – subsequent installation and commissioning will be a matter of a few hours. Also, bring this requirement to the attention of your design office.
Preparing the electrical installation for high-power charging
A three-phase cable connected to a separately fused circuit should be available in the garage or in front of the house. Even as electric vehicle owners, you may not use 22 kW charging power today, but in the future this will be different. Therefore, prepare the electrical installation so that it does not limit you – a circuit for a powerful 22 kW wallbox must be equipped with a 3×32 A circuit breaker, and the main breaker should be up to 3×40 A.
At the same time, the more powerful the connection, the higher the monthly fees. So think carefully about what power you will realistically use within the next few years. In the beginning, a lower power may be sufficient, or you may not be charging at all yet. But definitely insist on an electrical installation where future upgrading of the main breaker value will be straightforward. This relates, for example, to cable lengths, cross-sections and routing.
Do not forget to prepare data cables
Modern charging stations support dynamic load management or integration with PV systems and SmartHome components. In order to communicate with other electronic devices, they need to transmit data. We therefore recommend connecting the MyBox charging station installation location with the main distribution board using a multi-core UTP cable. We also recommend ensuring the availability of a quality internet connection for cloud usage and remote management.
Wallbox in an existing house and electrical installation modifications
With new builds, you can prepare for powerful home charging in advance. What awaits you if you want to create a charging point in an existing or older family house? Before commissioning, we definitely recommend carrying out an electrical installation inspection. During charging, there is a high load on the electrical distribution. As for the modifications themselves, it depends on the required power.
MyBox charging stations, whether MyBox Home or MyBox Profi, can be connected not only to three phases but also to just one. You will not reach the maximum charging power, but the wallbox will still serve its purpose.
Dedicated circuit and circuit protection
Even in older buildings, you must ensure the wallbox is connected to a dedicated circuit with an adequate breaker value. For stations with a power of 11 kW/16 A, a 3×20 A circuit breaker is sufficient. So if your household has a standard main breaker value of 3×25 A, it could theoretically be enough. You can also get a 22 kW station – with the charging power limited.
However, if you want to use the station's full potential, i.e. 22 kW, you need a 3×32 A circuit. This usually also means upgrading the main breaker to 3×40 A, taking into account the use of other high-power appliances in the household. We also recommend choosing stations with dynamic load management support, which ensures automatic power regulation so that the breaker value is never exceeded.
Residual current device
According to applicable standards, a residual current device must be installed with every charging station. Some types of charging stations, such as MyBox Profi, have an integrated residual current device, so it does not need to be part of the distribution board. In contrast, the basic MyBox Home model does not have a residual current device, so it must be incorporated into the distribution board.
Upgrading the main circuit breaker
To request an upgrade of the main breaker value, you must contact your distribution network operator. They will assess whether the upgrade and the related station connection is technically feasible. If so, they will send you a contract proposal and quote the upgrade fee.
You then need to prepare the point of delivery – upgrade the breaker value and arrange an inspection report. In the final step, you request your electricity supplier to update the contract with the new main breaker value.
Changing the distribution tariff
You can reduce the operating costs of a home charging station by changing the distribution tariff to D27d, which is designed for households. However, we recommend calculating whether this change will be worthwhile considering the operation of other appliances that use the low tariff.
Contact your distribution network operator
You should contact the distribution network operator even if you do not need to upgrade the main breaker value or change the distribution tariff. A powerful station can also affect the operation of the distribution network itself – the operator must assess the feedback effects. Therefore, submit a request for permanent connection from the LV D2 level and wait for the assessment. Notification is required from a station power of 3.7 kW, so it also applies to smaller wallboxes.
Do you need advice on installing a home charging station and the related requirements? Contact us. We will be happy to answer your questions and, if you are interested, put you in touch with electrical installation companies that will handle both the preparation and the installation itself.
Author
Filip Zapletal
