The Deye SUN-K-G03 series are three-phase string-type grid-tie inverters, designed for commercial and industrial installations where reliable operation, flexible PV string design, and high grid energy quality are essential. What distinguishes them is the multi-channel MPPT, which facilitates yield optimization regardless of different roof orientations, uneven solar irradiance, or partial shading - preventing the entire system from being dragged down, allowing individual sections to operate closer to their own optimum.
In practice, the high European efficiency translates to significantly lower losses under typical operating conditions in Poland, supporting predictable annual energy production. The series also offers monitoring and communication in various configurations - from wireless solutions to wired communication with access to diagnostics and performance analysis via platform/app.
For safety and grid compliance, robust DC/AC protection and adherence to common grid connection standards (including EN 50549, VDE-AR-N 4105) are crucial, along with the manufacturer's standard warranty.
Ranking
Specifications
Pros and cons
The SUN-K-G03 series inverters achieve a maximum efficiency of 98.8% and a European standard of 98.2% (according to Deye's official datasheet for 70-110 kW variants), placing them among the top performers in the commercial segment of three-phase string inverters. This translates to conversion losses below 2% under typical operating conditions in Poland, directly resulting in a higher annual energy yield.
The series offers up to 6 MPPT channels with a wide input voltage range of 200-850 V DC, enabling independent optimization of PV strings on arrays with different orientations or under partial shading. Compared to inverters with 2-3 MPPT channels, this translates to a noticeably smaller impact of local losses on the overall system performance in commercially complex installations.
The series has confirmed TÜV/SGS certificates for the EN 50549-1:2019 standard and VDE-AR-N 4105, which is a requirement for grid connection in Poland, Germany, and most EU markets, eliminating the need for additional testing. Deye makes the full certification documentation publicly available on deyeinverter.com, simplifying the formal procedures for investors.
Within the G03 family, options range from 4 kW (G03-LV) to 30-60 kW and up to 70-110 kW, allowing the use of the same brand, monitoring ecosystem, and service procedures in projects of different scales. For developers managing a portfolio of commercial installations, this means simplifying the supply chain and standardizing maintenance processes.
The enclosure, rated IP65, provides durability in outdoor environments (operating range -25°C to +60°C), while the integrated interfaces - RS485, RS232, WiFi, LAN, GPRS, 4G, and Bluetooth - enable integration with SCADA systems and cloud-based monitoring without the need for additional communication modules. This is a significant advantage in industrial installations that require remote diagnostics.
While Deye has a service center in Poland (Warsaw, Aleje Jerozolimskie 212), users on the DIY Solar Power Forum report difficulties in coordinating support when purchasing through foreign distributors and delays in receiving service responses. Key players in the segment - SMA and Fronius - have a denser, contractually-defined network of authorized partners with guaranteed response times (SLA), which is important for maintenance and operation agreements for commercial installations.
According to the Wood Mackenzie (H1 2025) and PVBL Top 20 rankings for 2025, Deye ranks in the top 20 inverter suppliers, alongside Huawei, Sungrow, SMA, Fronius, and Solis/Ginlong, which together account for over 60% of global shipments. For projects requiring bank financing or due diligence audits by financial institutions, lower brand recognition may necessitate additional justification in the project documentation.
Alternatives
SolarEdge EV Charging Single Phase Inverter SE4000H (aka H4000SE / SE4000H)
4 kW
99.0%
-
11.4 kg
+1.5 pp efficiency, 1.4 kg heavier
About the SUN-K-G03 series
These answers cover the whole series. Where a figure differs, the specification above is this model's own.