Which inverters can be used with Dualsun SPRING & FLASH panels?

When selecting an inverter to convert the DC (direct current) electricity from DualSun panels into AC (alternating current) electricity, it is essential to ensure its compatibility with the panel. A panel is compatible with an inverter as long as the voltage and current ranges it can deliver fall within the operating ranges of the inverter, thus avoiding any risk of damaging the inverter.

In general, centralized inverters (for projects > 100 kWp) or string inverters (for projects < 100 kWp) are compatible with our panels. You can size them using the inverter manufacturer's website by selecting our panels in their software.

To select a centralized inverter, it is important to know the characteristics of your solar field:

• Total peak power of the installation (Wp)

• Open-circuit voltage (Voc)

• Short-circuit current (Isc)

• Nominal power current (Impp)

• Nominal power voltage (Vmpp)

The open-circuit voltage (Voc) is the maximum voltage output of the installation, which depends on the number of panels in series in each string.

The short-circuit current (Isc) is the maximum current output of the installation, which depends on the number of parallel strings in the system.

For panels connected in series, the string's short-circuit current (Isc) equals the short-circuit current of a single panel (Isc). For panels connected in parallel, the open-circuit voltage (Voc) equals the open-circuit voltage of a single panel (Voc).

These values should be compared with the "Voc max" and "Isc max" values in the centralized inverter's datasheet.

The choice and sizing of the inverter should be done with the manufacturer or distributor, who will consider all the constraints of their equipment and optimize the panel string configuration. A simulation using dedicated software can help determine the most suitable inverter.

Here are online tools from various manufacturers:

• Fronius Solar Creator

• SMA Sunny Design

• SolarEdge Designer

• Huawei Smart Design

The process is similar to choosing a centralized inverter, with the difference that the Voc and Isc values to consider correspond to a single panel (not the entire system).

Microinverter datasheets typically include the following data (though naming may vary):

• Operating voltage range - Maximum and minimum voltage the microinverter can accept as input (V)

• MPP voltage range - Minimum and maximum voltage at which the microinverter starts converting to AC (V). If the panel voltage is outside this range, it is still compatible, but the microinverter will not start production until the panel voltage falls within this range.

• Maximum DC short-circuit current - The physical limit of the microinverter's DC input (Isc max), which must be checked for compatibility.

• Maximum input current - The maximum current the microinverter can receive (A), corresponding to the maximum current managed by its internal MPPT, usually labeled Iscc. This is the maximum current the microinverter can convert. If the panel can theoretically supply a higher current, it is still compatible.

• Maximum AC output power - The maximum power output by the microinverter. If the panel can theoretically deliver a higher power, it is still compatible.

If you are using microinverters or optimizers, it is essential to verify their compatibility with our panels. Installers from our partner network can provide expert advice on the most suitable equipment for your project.

Compatibility Table

Our compatibility table differentiates between several types of compatibility:

• Not compatible: The inverter's operating limits may be exceeded, potentially damaging the inverter.

• Compatible: The panel's voltage and current will always be within the inverter's operating range.

• Compatible but may clip at NMOT: The panel's voltage and current will almost always be within the inverter's operating range. However, under optimal and realistic production conditions, power may be clipped.

Note: This table is provided for reference only. It is necessary to verify compatibility with the microinverter or optimizer manufacturer. These manufacturers should provide guidance on the usage conditions and limits of their products, particularly via the DualSun product manuals.

Here are the compatibility calculators from different manufacturers:

• Enphase Calculator

• APsystems Calculator

• SolarEdge Designer

• Huawei Smart Design

• Hoymiles Calculator

Special Case: Huawei Optimizers

There is a specific case for Huawei optimizers. If the module's Isc or Pmax exceeds the optimizer's Isc or Prated, energy production may be limited in certain specific situations. According to Huawei, this does not pose a compatibility issue.

Power clipping is a limitation of the inverter's output power. This occurs when the photovoltaic panel's output power exceeds the inverter's maximum output power. When clipping occurs, the inverter’s daily production curve may flatten during peak production hours.

The impact of clipping on annual production is often negligible. To verify this, a financial study based on a simulation can be conducted to determine whether the energy loss from clipping outweighs the cost difference of a more powerful microinverter.

Clipping is like buying a city car for 20 days of highway driving per year while using it in the city for the other 345 days. It doesn’t matter if, during those 20 days, you're limited to 110 km/h—after all, the time “lost” by not driving at 130 km/h isn’t worth the cost of a supercar! In this analogy, the car represents the microinverter. There is no need to get a microinverter as powerful or more powerful than the panel, as the ideal conditions for reaching the PV module’s maximum power are rarely met.

For bifacial modules, if the installation type significantly impacts the power gain, Voc and Isc values must be considered under BNPI conditions—standard conditions that account for rear-side power generation.

To learn more about bifacial modules, consult the related FAQ: What is a bifacial module? What performance gains does it offer?

No, there is no risk of microinverters or optimizers overheating under bifacial modules. The transparency rate of a bifacial panel is around 1%. The amount of sunlight passing through the panel and directly hitting the inverter is negligible compared to a non-transparent module.

Inverters and microinverters are designed to operate within temperature ranges commonly found under both bifacial and monofacial panels. If temperatures exceed a certain threshold (typically between 60°C and 80°C, depending on the manufacturer), the microinverter or optimizer will enter degraded operation mode before shutting down due to overheating.