What is the Virgo 4K6-S and who is it for?
The Virgo 4K6-S is a 4.6 kW single-phase hybrid inverter designed for Heiwit sodium-ion batteries. In a single unit, it manages the solar PV system, the storage system, the grid and the household’s electrical loads.
It supports up to 9 kW of solar panels on two independent MPPT trackers, with an input voltage of between 100 and 550 V. The two strings can face different directions, for example east and west.
On the energy storage side, it operates at 48 V using Heiwit sodium-ion batteries. Up to three 10 kWh modules can be connected in parallel, giving a total of 30 kWh. The maximum charging and discharging power is 5 kW.
When the mains supply fails, the built-in UPS function switches over within 10 milliseconds. The backup output delivers 4.6 kW. The inverter can draw up to 40 A from the mains to recharge the battery.
The maximum efficiency is 97.6 per cent and the European efficiency is 97.3 per cent. The protection rating is IP66 and the operating temperature range is from −25 °C to +60 °C, with a reduction in power output above 40 °C. Cooling is natural, without fans, and noise levels remain below 25 dB. It is designed for wall mounting.
Monitoring is carried out via the app or the display, with a Wi-Fi, Bluetooth or GPRS connection. The data remains on Italian servers. Three units in parallel can form a three-phase output; for three-phase loads, Heiwit also offers theLybra inverter.
The Virgo 4K6-S carries the CE mark. It is also certified to CEI 0-21:2022 for connection to the Italian grid, issued by TÜV SÜD. It comes with a 10-year warranty, and support is handled directly in Italy. It is sold and installed exclusively through the Heiwit network of installers.
Virgo 4K6-S: frequently asked questions
Which batteries does the Virgo 4K6-S support?
Only 48 V Heiwit sodium-ion batteries, with up to 3 units connected in parallel for a storage capacity of 30 kWh, and a maximum charge and discharge power of 5 kW.
Does it work during a power cut?
Yes. The built-in UPS function switches from the mains to the battery in 10 ms and supplies up to 4.6 kW to the backup output.
How much photovoltaic capacity can I connect to the Virgo 4K6-S?
Up to 9 kW of input power across 2 MPPT channels with a range of 100–550 V, one string per MPPT channel, maximum voltage 600 V.
Can it be used on a three-phase supply?
The Virgo is single-phase; three units connected in parallel can provide a three-phase output. For three-phase loads, Heiwit also offers the Lybra hybrid inverter.
Can it be installed outdoors?
Yes. The protection rating is IP66 and the operating temperature ranges from −25 °C to +60 °C, with a reduction in power output above 40 °C. Wall-mounted, naturally cooled, with a noise level of less than 25 dB. The battery, however, must only be installed indoors.
Is the Virgo 4K6-S CEI 0-21 certified?
Yes. The Virgo 4K6-S with the Heiwit battery is CEI 0-21 certified by TÜV SÜD on the basis of type testing (document no. D 132944 0003). It also carries the CE marking.
Is the Virgo 4K6-S certified for the German grid?
Yes. The Virgo 4K6-S has VDE-AR-N 4105:2018 certification, issued by TÜV SÜD in September 2026. This is the standard for connection to the German low-voltage grid. There are two certificates: the unit certificate (no. ESY 132944 0008) and the certificate for the network and system (NS) protection integrated in the inverter (no. ESY 132944 0009). The tests follow DIN VDE V 0124-100:2020.
Who is responsible for the warranty and after-sales service?
Heiwit, directly in Italy, with a 10-year warranty. Monitoring data is stored on Italian servers and the inverter is sold and installed only through the Heiwit installer network.