Qcells Q.HOME ESS HYB-G3 (pv)
The Qcells Q.HOME ESS HYB-G3 is a modular hybrid inverter and battery storage system for residential solar self-consumption, available in single-phase and three-phase variants. This template communicates over Modbus RTU via RS485 and reads PV production data: DC power from string 1 (power_a), DC power from string 2 (power_b), and cumulative energy yield (energy). With these registers in ModbusCloud, installers can track solar generation trends, detect string underperformance, and verify long-term yield against commissioning estimates.
- Protocol
- Modbus RTU
- Connection
- RS485
- Registers
- 3, read only
- Brand
- Qcells
- Compatible models
- Hybrid X1/X3 G3/G4 · Q.HOME ESS HYB-G3
- Last updated
Registers (3)
3 read, 0 write
| Name | Unit | Access | Address (Hidden until you enter your email) | Function (hidden) | Type (hidden) |
|---|---|---|---|---|---|
| power_a | W | Read | |||
| power_b | W | Read | |||
| energy | Wh | Read |
Loading registers…
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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 PV string 1 and string 2 power in real time to detect shading or soiling on individual arrays.
- Track cumulative energy yield over time to verify annual production against installer guarantees.
- Alert on an unexpected drop in power_a or power_b to identify a failed string or MPPT fault.
- Compare string 1 and string 2 output to spot imbalances caused by mismatched panel orientations.
- Report daily and monthly energy totals from the energy register to support tenant or owner billing.
Installation
Enable Modbus RTU on the Q.HOME ESS HYB-G3 by navigating to Advanced Settings on the inverter display, then entering the Modbus section and confirming the baud rate (default 19200) and slave address (default 1).
Connect the ModbusCloud Gateway to the inverter RS485 COM port using an RJ45 cable: wire pin 4 (A+) and pin 5 (B-) of the RJ45 to the corresponding A and B terminals on the Gateway's RS485 interface.
In the ModbusCloud portal, add a new device, select the Qcells Q.HOME ESS HYB-G3 (pv) template, and assign the unit ID matching the slave address configured on the inverter (typically 1).
Verify the connection by checking the live readings for power_a and power_b during daylight: both registers should return non-zero watt values when PV strings are producing.
Things to watch for
Why do power_a and power_b always read zero, even in sunshine?
Confirm the inverter is in on-grid or self-use mode and that PV strings are active. Also verify the baud rate on both the inverter display and the Gateway match exactly. A mismatch, even one step off (for example 9600 vs 19200), will produce silent failures where the Gateway connects but returns no valid data.
The Gateway shows a connection but all three registers return errors. What is wrong?
Check that the RS485 A and B wires are not swapped. On the RJ45 COM port, pin 4 is A+ (positive) and pin 5 is B- (negative). Reversed polarity causes framing errors on the Modbus RTU bus without breaking the physical link, so the connection appears alive but all reads fail.
The energy register rolls back to zero unexpectedly. Is this normal?
The energy register is a uint32 cumulative counter. At very high lifetime totals the counter can overflow and restart from zero. Cross-check the portal's historical trend to distinguish a genuine overflow from a communication dropout that caused a missed reading, which can also appear as a reset.
Two inverters are on the same RS485 bus and readings are unreliable. How do I fix this?
Each device on a shared RS485 bus must have a unique Modbus slave address. On the Q.HOME ESS HYB-G3, change the address in Advanced Settings on the inverter display. Assign one unit a unique ID, then update the corresponding ModbusCloud device entry to match. Ensure only one master (the Gateway) polls the bus.
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