Which wallbox should I buy?
Not every wallbox is suitable for PV surplus charging or charging with solar power. We want to give you an overview of which functions your wallbox must have, what they mean and which wallboxes are suitable for PV surplus charging.
Internet capability
In order for us to be able to control and read out your wallbox, it must be connected to the Internet. Modern wallboxes can connect to the internet via a mobile network, Wi-Fi or Ethernet. You are most flexible with a WLAN or mobile phone connection, which saves installation costs and is usually available everywhere.
Communication
We can control your wallbox directly via your wallbox manufacturer's server using an API (Application Programming Interface). Access authorization is mainly granted via your user name and password from the manufacturer app or via an API/cloud token. All data is transmitted in encrypted form.
Some wallboxes have an OCPP interface (Open Charge Point Protocol), which is a standardized protocol that we can use to communicate with your wallbox. Theoretically, it is possible to control any OCPP-capable wallbox via this.
Variable power adjustment
So that we can optimally adapt the charging power to the surplus solar power, the charging power must be adjustable. Electric cars can usually be charged from 6 to 16 A. Some manufacturers even support charging capacities of up to 32 A. The charging power of your wallbox should be adjustable in 1 A steps.
Phase switching
To get the most out of your self-generated electricity, your wallbox should be able to switch between 1-phase and 3-phase charging. In concrete terms, this means that you can charge on one phase with 1400 to 3600 W and on 3 phases with 4200 to 11000 W (6 - 16 A) charging power. If your car and your wallbox can charge up to 32 A (22 kW), this is also supported by us, as is charging on 2 phases.
Some current wallboxes can switch between one and three phases during the charging process. Older models do not support this switching. However, you can also connect these wallboxes to one phase or three phases, depending on what best suits the size of your PV system. The phases must then be switched manually.
Load management
If you have several wallboxes, it may be important that your wallbox has load management. The load management of the wallboxes guarantees that your fuse is not overloaded. For example, if your wallboxes are fused with 16 A, then either one car can charge with 16 A or two cars with 8 A. The wallboxes themselves determine the maximum charging power. We have no influence on this.