SolaX X3-MGA-40K-G2 Three-phase Inverter 40 kW
The SolaX X3-MGA-40K-G2 is a 40 kW three-phase string photovoltaic inverter from the X3-MEGA G2 series for commercial, industrial, and ground-mounted systems: 4 MPPT with 8 string inputs, up to 60 kWp PV array, maximum efficiency 98.4%, IP66, Type II SPD on DC and AC side, string current monitoring, and I-V curve diagnosis.
The SolaX X3-MGA-40K-G2 inverter is a 40 kW three-phase string photovoltaic inverter from the X3-MEGA G2 series, SolaX’s commercial and industrial range. It is the entry-size model in the series and features 4 MPPT trackers with 8 total string inputs.
String monitoring and I-V diagnosis: maintenance that pays for itself
In a 60 kWp array, there are dozens of strings and a single fault cannot be seen from total production: a failed module or an oxidized connector gets lost in the statistical noise. The X3-MEGA G2 integrates current monitoring for each individual string and I-V curve diagnosis, identifying the underperforming string without having to go up on the roof with a clamp meter. On ground-mounted systems or large industrial roofs, this is the difference between noticing a problem within a week and noticing it at the end of the year when reading the final reports.
SolaX X3-MGA-40K-G2 technical specifications
| Rated AC power | 40 kVA three-phase 3W/(N)/PE 230/400 V |
| Maximum apparent power | 44 kVA (AC overload 110%) |
| Rated / maximum output current | 58 A / 63,8 A (at 230 V) |
| Recommended PV power | 60 kWp (oversizing 150%) |
| MPPT / strings per MPPT | 4 / 2 (8 inputs) |
| Maximum current per MPPT | 32 A (Isc 46 A) |
| Maximum / nominal PV voltage | 1100 V / 600 V |
| MPPT range / start-up voltage | 180-1000 V / 200 V |
| Maximum / European efficiency | 98,4% / 98,1% |
| Protection rating | IP66 |
| Operating temperature | -25 / +60 °C |
| Night-time consumption | below 2 W |
| Diagnostics | String current monitoring, I-V curve diagnosis, 24-hour monitoring |
| Protections | Type II SPD on DC and AC side, optional AFCI, external anti-PID |
| AC auxiliary power supply (APS) | Integrated |
| Dimensions / weight | 630 x 521 x 286 mm / 44 kg |
Four trackers for 60 kWp: how to distribute them
The recommended 60 kWp corresponds to 150% of the rated power, around 133 450 Wp modules, to be distributed across 4 MPPT with 2 strings each. Each tracker accepts 32 A of operating current and 46 A of short-circuit current, values that allow two strings to be connected in parallel even with high-current modules. Four independent trackers mean four groups with different orientation, tilt or string length: on a shed roof or a ground-mounted system with staggered rows, this is the condition required to avoid dragging the entire array to the operating point of the worst-performing string.
Connection: what to check before ordering
At 40 kW, the system is well above the 11,08 kW threshold of CEI 0-21 and requires an interface panel with SPI relay, external interface device and test report. However, two checks must be carried out first: the available feed-in power at the connection point, which the distributor may grant in low or medium voltage with very different requirements, and the electricity production workshop obligations, which apply above 20 kW of power with registration with the Customs Agency, energy accounting and annual declaration. The datasheet lists EN 50549 and VDE4105 certifications: for Italy, the country code must be set and the manufacturer’s declaration of conformity with the applicable grid connection standard must be verified.
Frequently asked questions
How many MPPTs does the SolaX X3-MGA-40K-G2 have?
Four, with 2 strings each, for a total of 8 string inputs. It is the model with the fewest trackers in the X3-MEGA G2 series: the 50 kW has 5 and the 60 kW has 6. Each MPPT accepts 32 A of operating current and 46 A of short-circuit current.
How many panels can I connect to a 40 kW inverter?
The recommended PV power is 60 kWp, equal to 150% of the rated power: around 133 450 Wp modules on 8 strings, therefore 16-17 modules per string. The voltage limit is 1100 V, so the string length must be checked against the open-circuit voltage at the minimum design temperature.
What is I-V curve diagnosis used for?
It allows the inverter to trace the current-voltage curve of each string and compare it with the expected curve, identifying degraded modules, abnormal shading, high-resistance connections or mismatch. Together with current monitoring for each individual string, it makes it possible to locate the problem before inspection, reducing maintenance time and costs on large arrays.
Which current should be considered for AC cable sizing?
The rated output current is 58 A at 230/400 V, but sizing must be based on the maximum continuous current of 63,8 A, corresponding to the 110% overload. The X3-MEGA G2 series also allows connection with an aluminium AC cable, a useful option for reducing costs on long runs.
Can it operate in dusty environments or on ground-mounted systems?
Yes, the IP66 rating and the range from -25 to +60 °C make it suitable for outdoor installation, including agricultural or industrial environments. Cooling is by smart ventilation, with fans that activate only when the temperature requires it: the grilles should be checked periodically where there is dust, silos or processes that cause dirt build-up.
