Growatt MAX 320-350K-X series represents advanced grid-tie inverters (grid-tie) of the utility-scale category, designed for large PV farms and industrial installations, where stable operation, low losses, and easy service support are crucial. The application of 6 MPPT facilitates precise optimization of yields in fields with different orientations and uneven shading-instead of pulling down entire sections, the inverter can more effectively manage the operation of individual string groups.
High European efficiency translates into significantly greater energy production under typical operating conditions in Poland, i.e., varying temperatures and partial loads. In practice, this means better investment profitability and lower energy costs throughout the installation's entire lifecycle.
A key feature of the series is the emphasis on safety and resilience-Type II surge protection on both the DC and AC sides and IP66 protection rating assist in operation within challenging farming environments. Monitoring and diagnostics are prepared for remote management, and communication can be expanded with PLC for simplified infrastructure. This is the choice for EPCs and investors who expect scalability, control, and predictable yields.
Ranking
Specifications
Pros and cons
The declared maximum efficiency of 99.03% places this series among the top performers in utility-scale string inverters; comparable models from Sungrow (SG350HX) achieve 99.0%, and SMA SUNNY CENTRAL 2750-EV approximately 98.7%. The percentage difference translates to an additional 50-60 MWh/year in output for installations of 10 MWp.
The 75A MPPT input current acceptance allows for native compatibility with large-format modules (182 mm / 210 mm, bifacial up to ~700 Wp), eliminating the need for additional string combiners. With a total of 30 string inputs, the DC layout on large farms is simplified.
The maximum input voltage of 1500 V allows for longer strings and lower BOS (balance of system) costs (fewer cables, lower resistive losses). A DC/AC ratio of up to 1.5 allows for intentionally over-sizing the PV array relative to the AC inverter's power, which, in the conditions typical of Poland (high partial loads), actually improves the power utilization factor and reduces the payback period.
The IP66 level of protection, along with built-in Class II surge protection on both sides, eliminates the need for external protection in typical pharmaceutical applications, reducing electrical project costs and simplifying installation certification.
The integrated I/V curve measurement at the single string level enables remote detection of faults without the need for on-site service personnel. Optional PLC communication allows for the elimination of a separate communication cabling layer on the farm, which, for installations >5 MWp, significantly reduces the CAPEX of the telemetry infrastructure.
Growatt does not appear on the BloombergNEF list of bankable inverter manufacturers (as of 2025/2026; status: tier_1_bankable: false, according to the manufacturer's data). Banks that finance utility-scale projects using non-recourse project finance methods (EBI, EBRD, ING) often require inverters from BNEF Tier 1 manufacturers. The absence of this status can make it more difficult or expensive to obtain long-term financing, particularly for projects over 5 MW seeking institutional funding.
Alternatives
About the MAX 320~350K-X series
These answers cover the whole series. Where a figure differs, the specification above is this model's own.