Growatt Modbus Register 48: Devicename AcPower PAC3

Technical Definition

The register devicename AcPower PAC3 at address 48 is used to monitor devicename acpower pac3 on the Growatt.

• Protocol: Modbus RTU
• Data Type: U DWORD
• Unit: W
• 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 devicename AcPower PAC3 (Address: 48)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=48, 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: "devicename AcPower PAC3"
  address: 48
  value_type: U_DWORD
  unit_of_measurement: "W"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

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

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

💡 Engineer's Insight

Analysis: AC Power Output for Phase 3 (W). Real power delivered to the grid.

Troubleshooting: Review voltage and current readings, check inverter operational status, or load constraints.