How many SMA EV Charger can I operate with one Sunny Home Manager 2.0?
The Sunny Home Manager 2.0 currently supports one SMA EV Charger. We expect that it will be possible to connect up to three SMA EV Charger to one Sunny Home Manager 2.0 by the middle of the year. This configuration for home use will then also be supported by the SMA Energy app.
The 5 m charging cable supplied as standard is too short for my application. Does SMA also offer longer charging cables?
At mid-year, 7.5 m and 10.0 m long charging cables will also be available as an option. For installers, the cables will then be available as spare parts via the SMA Online Shop for retrofitting in existing systems. As an end customer, please contact your installer directly, as the SMA Online Shop offer is aimed exclusively at specialist installers.
SMA EV Charger has two switch positions, but offers three different charging modes. How can I switch between them?
You can switch between fast charging and optimized charging using the rotary switch on the SMA EV Charger enclosure. Note, however, that you cannot configure fast charging mode via the SMA Energy app. If you set the rotary switch to the optimized switch position, SMA EV Charger will begin PV-optimized charging by default. Alternatively, you can then set a desired charging target via the SMA Energy app.
The documentation contains frequent references to the “slider.” Where can I find this, and what does it do?
You can find the “slider” in the Sunny Portal by choosing load characteristics > optional energy requirements. In optimized charging mode, your electric vehicle will be charged with the minimum share of solar energy for SMA EV Charger. Depending on how your system is configured, for example, you should allow 20% grid-supplied power to ensure that the Sunny Home Manager 2.0 also performs scheduling for small PV systems or can take into account variable weather conditions. Rather than a static value, this figure is more of a target that the Sunny Home Manager 2.0 will aim to achieve throughout the day (see Figure 2).
Figure 2: Depending on how your system is configured, you should allow a certain share of grid-supplied power in optimized charging mode to ensure that the Sunny Home Manager 2.0 also performs scheduling for small PV systems or can take into account variable weather conditions. This can be set using the slider in the Sunny Portal.
I have configured the slider for SMA EV Charger in the Sunny Portal for 100% PV power generation, but the SMA Energy app still shows only a small amount of grid-supplied power. Why is this?
The Sunny Home Manager 2.0 regulates SMA EV Charger at one-minute intervals. Especially when conditions are variable, this may result in a discrepancy with respect to the actual level of PV power generation. So even if you have set 100% power generation, it is still possible that only a small amount of charging power is actually drawn from the utility grid. In addition, planning is done by the Sunny Home Manager 2.0 based on a schedule (hypothesis). Regular changes due to unforeseen events are absolutely normal.
What are the different sources of energy used for charging my vehicle in the different charging modes?
During fast charging, the vehicle is charged with the maximum power that the vehicle and house allow. Any energy source is used here, so the system could potentially be drawing power from the home storage system to charge your vehicle.
During PV-optimized charging, SMA EV Charger charges the vehicle with the energy mix saved in the Sunny Portal (slider). Charging of battery prior to optional loads checkmark decides whether the battery or OPTIONAL load is supplied with the surplus solar power initially. Depending on how the slider is set, energy from the home storage system or utility grid can also be used to charge the vehicle.
During forecast-based charging, surplus solar energy is initially used for achieving the charging target configured in the SMA Energy app. If not enough of this energy is available for achieving the charging target, the home storage system is used. Once the home storage system is used up, the energy is drawn from the utility grid.
Is SMA EV Charger suitable for bidirectional charging? Will a DC charger be available?
SMA EV Charger is designed for unidirectional AC charging of the electric vehicle in accordance with IEC 61851-1. Bidirectional DC charging at home is therefore not possible. This is prevented in particular by regulatory conditions. In addition, the galvanic isolation prescribed by the applicable standards results in high original costs for charging solutions. Vehicle manufacturers are increasingly offering vehicle models with communication in accordance with ISO 15118, thereby potentially enabling bidirectional applications. SMA is monitoring developments in this area with great interest.
Under what conditions can I receive KfW 440 funding for SMA EV Charger?
SMA EV Charger 22 is eligible for funding. When setting up your system, the solar power professional has to limit the device to a charging power of 11 kW (see manufacturer’s declaration the product page download area*). In addition, all the power for charging the electric vehicle has to come from renewable energies. This can be demonstrated by either concluding a green electricity contract (e.g., SMA JOIN) or submitting a self-declaration that the vehicle is charged exclusively using self-generated solar power. Once your request has been approved by the KfW, you have to install your system within nine months and submit the necessary documentation.
My SMA EV Charger does not begin charging until a large amount of surplus power is available. The vehicle is not charged if only a small amount of surplus photovoltaic power is available. Why might this be?
When SMA EV Charger is installed, it is vital that the charging cable supplied is connected as shown below (see Figure 3). If the lines are not connected as shown, single-phase charging cannot start. Three-phase charging begins only when a large amount of surplus power is available. The charging cable must be installed only by an electrically qualified person.
Figure 3: The charging cable must be connected as shown by an electrically qualified person (brown line to L1) because otherwise automatic phase-switching will not be possible.
I have restricted SMA EV Charger to 11 kW. Why doesn’t it perform single-phase charging with more than 3.5 kW now?
This is because the maximum charging power of SMA EV Charger is currently restricted based on current. When restricted to 11 kW, the maximum charging current of the device is 16 A. To prevent the device’s fuse protection level being exceeded, single-phase charging of the vehicle will not exceed 3.5 kW either. This problem will be fixed in a future software update so that, if the electrical installation permits (e.g. line cross-sections, fuse protection), single-phase charging with up to 7.4 kW will be possible even when SMA EV Charger is restricted to 11 kW.
I want to charge my vehicle up to a maximum of 80% SOC (state of charge). How can I set this?
The SoC of the vehicle battery is not transmitted to the vehicle via PWM communication (pulse width modulation) as standard during charging in accordance with IEC 61851-1. The SMA EV Charger therefore has no current information on the state of charge of the vehicle battery and cannot use this information to optimize energy management.
Can the charger read the state of charge (SOC) of the connected vehicle via powerline communication (PLC)?
No, because there is no standard transmission of the SoC via PWM communication (pulse width modulation) from the vehicle to the charging station.
Which conditions have to be fulfilled so that the integrated boost function can be used?
The integrated boost function enables single-phase charging with up to 7.4 kW. The integrated symmetry feature ensures that the country-specific unbalanced load limit (4.6 kW in Germany) is adhered to at all times. This is possible, however, only when a single-phase (battery) inverter is connected in the same phase as SMA EV Charger. A three-phase inverter feeding into the grid is not sufficient here. Alternatively, large loads can be connected in the other two phases. The boost function itself does not need to be activated. As soon as solar power is available and the necessary conditions have been fulfilled, power from the utility grid and solar power are automatically combined for faster charging.
SMA EV Charger ensures greater safety for my house connection. Which parameter can be used as a reference here?
Thanks to power outage protection, SMA EV Charger can be easily integrated into an existing energy system at any time. Optimal utilization of the available connection capacity means that the house connection does not need to be expanded. When multiple loads are operated in parallel, SMA EV Charger automatically and dynamically reduces the charging power of the electric vehicle before a critical overload is reached, which prevents fuses from blowing. When the solar power professional sets up the system, the nominal current of the selective main miniature circuit breaker and not the SMA EV Charger fuse protection should be specified under “nominal current of the point of interconnection” (see Figure 4).
Figure 4: For power outage protection, the solar power professional specifies the nominal current of the selective main miniature circuit breaker and not the SMA EV Charger fuse protection under “nominal current of the point of interconnection” when setting up the system.
I drive a Renault ZOE. What minimum charging current do I have to set?
As standard, the minimum charging current is set to 6 A (in accordance with IEC 61851-1) (see Figure 5). Depending on the vehicle connected, this may need to be changed. Due to its internal charging electronics, the Renault ZOE charges without any issues only from a charging current of 10 A. Ask your vehicle manufacturer about the minimum charging current for your vehicle. Any change to this value also affects the start of charging and the switching threshold of automatic phase-switching.
Figure 5: Depending on your vehicle, you may have to change the minimum charging current. Ask the vehicle manufacturer.
People always think that the electric vehicle’s on-board charger is destroyed during automatic phase-switching. How does SMA EV Charger deal with this?
Automatic phase-switching by SMA EV Charger enables maximum utilization of self-generated solar power. This poses no danger to the electric vehicle’s on-board charger because there is a 120-second changeover pause between single- and three-phase charging – in other words, active single-phase charging is stopped and three-phase charging is activated after a short wait (see Figure 6). An integrated hysteresis prevents constant switching between the phases.
SMA phase-switching is like a manual interruption in the charging process and causes no vehicle damage when the equipment is properly installed and configured (relay switchover time).
Figure 6: With automatic phase-switching, active single-phase charging is stopped and three-phase charging is activated after a short wait.
My SMA EV Charger has been installed at a location that can also be accessed by third parties. How can I prevent possible charging by unauthorized third parties?
Provided that no digital signal source (e.g., ripple control receiver, remote terminal unit) is connected, the digital inputs of SMA EV Charger can be used to connect, for example, an external key switch. This means that an external key switch can be connected to the fast stop and configured during commissioning via grid management services > active power control. This ensures that charging will not start until it has been approved.
Configure active power control only if a digital signal source is connected to the digital inputs of SMA EV Charger. Without this, SMA EV Charger will not charge the vehicle because it is still waiting for charging approval via the digital inputs. Activation of the function can be found in the log book of the Sunny Portal as the “active power limit” / “fast stop active” message.
Does SMA EV Charger allow me to settle charging costs via my employer or tax office?
I use SMA EV Charger 22. When I insert the charging cable into our ID.3 but do not want charging to start immediately, charging does not start at all. The wallbox seems to “fall asleep” in the process.
This is a known issue with first-generation ID.3 models which can only be solved by a software update of the vehicle. Within the framework of our in-series field tests with various vehicle models, we observed that the vehicles no longer “fall asleep”, even during optimized charging, following the extensive software update 2.1.
During PV surplus charging, the ID.3 “falls asleep” when charging power is temporarily unavailable (e.g., due to a passing cloud or if a washing machine is running). The fault seems to lie with VW here. Is it worth talking to VW about this? According to the VW customer service team, everything is working as it should.
During our in-series field tests, we noticed that the problem with updating the vehicle to version 2.1 has been fixed.
Why is SMA EV Charger more expensive than other wallboxes?
Charging with the SMA EV Charger is not only about charging the electric vehicle, but rather the fact that the solar power generated from your system can be used intelligently for this purpose. E-mobility is only sustainable when the charging current comes from renewable energy sources. Thus, it is the intelligence of the SMA EV Charger that makes the device slightly more expensive than standard wallboxes at first glance. However, it enables you to make the best possible use of your valuable solar power through intelligent functions such as automatic phase-switching. As a result, you can charge sustainably at an unbeatable low cost. Using the flexible charging modes, you can decide for yourself anytime whether you want your car to be ready to go quickly or whether you simply want to charge it in a particularly sustainable and affordable way.
Does the charger cause radio interference, potentially causing problems with amateur radio operators or the German Federal Network Agency?
SMA EV Charger meets the normative requirements for radio systems. The relevant EU Declaration of Conformity can be found in the download area of our product page.
Why is the charger not in the car?
The charger itself (AC on-board charger) is integrated in the vehicle. A wallbox / charging station is required to ensure compliance with the safety functions and control the charging process.