Solax X3-PRO G2 (pv)
The Solax X3-PRO G2 is a three-phase on-grid string inverter for residential and commercial PV installations, covering models X3-MIC G2, X3-PRO G2, and their Qcells-branded equivalents Q.VOLT P5T-X and Q.VOLT P17T-X. This ModbusCloud template reads the inverter over Modbus RTU via the RS485 port, collecting total AC output power, cumulative energy yield, and per-phase voltages and currents across all three phases. Connecting the Solax X3-PRO G2 to your ModbusCloud portal gives you continuous visibility into generation performance and phase balance without relying on a cloud service.
- Protocol
- Modbus RTU
- Connection
- RS485
- Registers
- 8, read only
- Brand
- Solax
- Compatible models
- X3-MIC G2 · X3-PRO G2 · Q.VOLT P5T-X · Q.VOLT P17T-X
- Last updated
Registers (8)
8 read, 0 write
| Name | Unit | Access | Address (Hidden until you enter your email) | Function (hidden) | Type (hidden) |
|---|---|---|---|---|---|
| power | W | Read | |||
| energy | Wh | Read | |||
| currents_a | A | Read | |||
| currents_b | A | Read | |||
| currents_c | A | Read | |||
| voltages_a | V | Read | |||
| voltages_b | V | Read | |||
| voltages_c | V | Read |
Loading registers…
Send your device list
If a device is not in the library yet, we build the template for free as soon as we have the register data.
Use cases
- Monitor total AC output power in real time to confirm the Solax X3-PRO G2 is producing at expected levels.
- Track cumulative energy yield over weeks and months to verify performance against system design estimates.
- Alert on phase voltage deviations across phases A, B, and C to catch grid asymmetry or connection faults early.
- Compare per-phase currents to detect string imbalances or failing MPPT strings on the X3-MIC G2 or X3-PRO G2.
- Report daily and monthly generation totals from the energy register to support yield guarantees and billing reconciliation.
Installation
Enable Modbus RTU on the inverter: navigate to the inverter display under Advanced Settings, find the Modbus or communication section, confirm the slave ID (default 1) and baud rate, and note both values.
Connect the ModbusCloud Gateway to the inverter RS485 port using a twisted-pair cable: pin 4 (A lead) to the Gateway RS485-A terminal and pin 5 (B lead) to the Gateway RS485-B terminal. Keep cable runs under 25 metres where possible.
In the ModbusCloud portal, add a new device, import the Solax X3-PRO G2 (pv) template, and set the unit ID to match the slave ID configured on the inverter display.
Spot-check the connection by reading the power register (address 1038): during daylight, the value should reflect live PV output. If the register returns zero or an error, verify baud rate and cable polarity.
Things to watch for
No data appears after importing the template. What should I check?
Confirm the Modbus slave ID in the portal matches the ID set on the inverter display. Also check that the baud rate in the portal matches the inverter setting, which defaults to 9600 or 19200 baud depending on firmware. A mismatch on either setting will cause all registers to return timeout errors.
Phase voltage registers return implausible values. What is wrong?
Solax X3-PRO G2 input registers report voltage with a scaling factor of 0.1, meaning a raw value of 2300 equals 230.0 V. If your portal display shows raw integer values without scaling applied, check your template scaling configuration. Confirm you are reading input registers using function code 4, not function code 3.
The gateway connects but power reads zero even in full sun.
The inverter only populates output registers when it is actively feeding the grid. If the inverter is in standby, fault, or night mode, the power register will return zero legitimately. Check the inverter display for any active fault codes before suspecting a communication problem.
RS485 communication is intermittent and drops regularly.
Check cable polarity: RS485 A and B leads must not be swapped. Ensure no other device on the same RS485 bus shares the same slave ID as this inverter. For bus runs longer than 15 metres, a 120-ohm termination resistor at each end of the bus can eliminate reflections causing framing errors.
-917%2Fcover.png&w=3840&q=75)
Want to see how it works?
