Device Growatt Spf Modbus Register 22: Name inverter name ac out voltage

Technical Definition

The register name inverter name ac out voltage at address 22 is used to monitor name inverter name ac out voltage on the Device Growatt Spf.

• Protocol: Modbus RTU
• Data Type: U WORD
• Unit: V
• Access: Read Only

How to Read (Python pymodbus)

Use this code snippet to read this specific value via RS485:

from pymodbus.client.sync import ModbusSerialClient

client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB0', baudrate=9600)
client.connect()

# Read name_inverter_name_ac_out_voltage (Address: 22)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=22, count=2, unit=1)

if not result.isError():
    print(f"Raw Value: {result.registers}")
else:
    print("Error reading register")

client.close()

Integration (Home Assistant)

Paste this into your configuration.yaml:

- platform: modbus_controller
  name: "name_inverter_name_ac_out_voltage"
  address: 22
  value_type: U_WORD
  unit_of_measurement: "V"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Device Growatt Spf]

    PLC -- "A+ (D+)" --> Device
    PLC -- "B- (D-)" --> Device
    PLC -- GND --> Device

💡 Engineer's Insight

Analysis: AC output voltage (V). Voltage supplied by the inverter to the load.

Troubleshooting: Zero if inverter is off or in fault state. Fluctuations may indicate grid instability or load issues.