"Charging with control by an external energy manager" involves the use of an external management system. The EMS controls all energy flows in a system (e.g. family home) including generation plant and solar power systems, energy storage systems and consumers such as washing machines or charging stations. Thanks to intelligent control of the energy flows and consumption, in the ideal situation only self-generated energy is used as a supply.
With "Charging controlled by external energy meter" a compatible meter from the Siemens PAC 2200 or TQ EM420 ranges is introduced at the home connection point. The meter determines the difference between grid consumption and energy generation, e.g. by the PV system, and sends this information to the wallbox via the network. The wallbox then intelligently controls the charging process with or without phase disconnection via various charging modes.
The automatic phase disconnection function is essential for optimum solar power charging. Depending on the available power of the self-generated energy from the PV system, the wall box automatically switches 2 phases off or on, to ensure an optimum charging process without interruptions. As soon as the charging current drops below a limiting value (4.1 kW for 3-phase charging or 1.4 kW for 1-phase charging), the charging process is terminated. This value represents the minimum required charging current.
Activation requires a software update to firmware version 5.33, which can be installed over-the-air if a network connection is available or locally via USB stick. Further information on the software update can be found here.
For solar power charging via an external enabling contact, the wall box is connected via a control line with the inverter to allow signals to be sent from the inverter to the wall box. As soon as a predefined PV surplus (minimum charging power) is present, the inverter begins the electric vehicle charging process by means of an enable signal. The power is supplied for as long as the surplus is being generated by the PV system.
