EmsTechLabs Logo EmsTechLabs

Growatt Modbus Register 8: Devicename PV2 DcInputCurrent

Technical documentation for Modbus register 8 on Growatt. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register devicename PV2 DcInputCurrent at address 8 is used to monitor devicename pv2 dcinputcurrent on the Growatt.

  • Protocol: Modbus RTU
  • Data Type: U WORD
  • Unit: A
  • 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 PV2 DcInputCurrent (Address: 8)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=8, 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 PV2 DcInputCurrent"
  address: 8
  value_type: U_WORD
  unit_of_measurement: "A"

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: DC Input Current from PV String 2 in A. Current from the second solar array. Scale: 0.1.

Troubleshooting: Zero if no sun, no load, or connection issue. Check for short circuits or loose wiring.