SolaX X3-GRD-350K-HV 350kW grid-connected string inverter, 3-phase

The Solax X3-GRAND-350K HV (MPN: 1030240116) is a grid-connected string inverter that has been specially developed for large-scale, ground-mounted PV systems and meets the highest requirements for efficiency and system integration. The3-phase inverter ensures stable and consistent feed-in to the grid, even under high loads and in complex system structures. With a nominal AC power of 350 kW and six independent MPPT trackers, each with 5 strings and up to 75 A input current per tracker, it enables precise power optimization and maximum energy yield. The robust housing is IP66-rated and is ideal for outdoor installations, even at altitudes of up to 5000 m. The integrated, self-cleaning airflow system minimizes dust deposits and thus reduces maintenance costs, significantly increasing the availability and service life of the system. In addition, an automatic trip switch improves safety and ensures reliable protection even in harsh outdoor conditions.

The Solax X3-GRAND-350K at a glance

• 3-phase system
• 6 independent MPPTs with 5 strings each
• Up to 75 A input current per tracker
• 500~1500V DC MPPT voltage range
• Self-cleaning airflow system
• Up to 99.03% efficiency
• Automatic trip switch
• I-U characteristic curve diagnosis
• Powerline communication (PLC)
• SVG function for grid support even during nighttime operation
• Temperature monitoring of AC connections
• 24-hour monitoring
• AFCI support (optional)
• Effective anti-PID protection (optional)
• Manufacturer product warranty: 5 years, information can be found here

6 MPPTs with 5 strings per tracker

The X3-GRAND HV inverters have six independent MPP trackers that enable flexible connection of module strings—with up to five strings per tracker. This allows the system to be easily adapted to different roof or terrain conditions, such as different module inclinations, orientations, or shading. Each tracker operates independently and ensures that the connected strings are always maintained at their optimum operating point. This precise control maximizes the performance of each individual string, making the GRAND HV ideal for high-performance PV modules.

Self-cleaning cooling system

The fan system with automatic direction reversal significantly reduces dust and dirt accumulation inside the device. This reduces maintenance and extends the service life of the components – particularly advantageous in dusty site conditions.

Powerline communication (PLC)

Communication via existing power lines eliminates the need for separate data lines and greatly simplifies system integration. This saves installation costs and reduces susceptibility to interference.

Grid stabilization at night (SVG function)

Even when there is no sunlight, the inverter contributes to voltage regulation in the grid. This supports grid quality and meets modern requirements for grid-friendly behavior of energy systems.

Intelligent fault diagnosis

Integrated I-U characteristic curve analysis and comprehensive real-time monitoring allow sources of error to be detected and rectified at an early stage. This increases operational reliability and reduces downtime during ongoing system operation.

Protective measures:

• overvoltage/undervoltage protection
• DC isolation protection
• DC reverse polarity protection
• Mains monitoring
• DC feed monitoring
• Feedback current monitoring
• Fault current detection
• overtemperature protection
• AC overcurrent protection
• AC short-circuit protection

Optional safety features

The SolaX X3-GRAND HV also offers important optional protection functions for increased operational safety: AFCI (Arc Fault Circuit Interrupter) support provides reliable protection against dangerous arcing, while effective anti-PID protection minimizes degradation of solar modules due to potential-induced degradation. In addition, optional surge protection devices (SPDs) of type I+II on the DC side and type II on the AC side are available to protect the inverter and connected components from surges and lightning strikes.

Technical data

PV input

• Max. PV input power per MPPT: 525kWp
• Max. PV input voltage: 1500V
• PV nominal input voltage: 1080V
• Operating voltage range: 550 - 1500V
• MPPT voltage range: 500 - 1500V
• Start output voltage: 550V
• Number of MPP trackers: 6
• Number of strings per MPP tracker: 5
• Max. input current per MPPT: 75A
• Max. input short-circuit current per MPPT: 115A

AC output

• Nominal output power: 350kW
• Nominal output current: 252.6A
• Max. apparent output power: 352kVA
• Max. continuous output current: 254A
• AC rated voltage: 3 / PE, 800 V
• AC rated frequency: 50Hz / 60Hz
• THDi (rated power): <3%

Efficiency

• Max. efficiency: 99.03%
• European efficiency: 98.80%

General:

• Dimensions: 1225 x 825.5 x 369.1 mm
• Net weight: <130 kg
• Protection class: IP66
• Operating temperature: -30°C to +60°C
• Humidity: 4-100% (condensing)

Scope of delivery

1x Solax X3-GRD-350K-HV grid-connected string inverter, 3-phase