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My Inverter%203 2Kw Modbus Register 4538: AC Input Voltage Range

Technical documentation for Modbus register 4538 on My Inverter%203 2Kw. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register AC Input Voltage Range at address 4538 is used to monitor ac input voltage range on the My Inverter%203 2Kw.

  • Protocol: Modbus RTU
  • Data Type: U WORD
  • Unit:
  • 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 AC Input Voltage Range (Address: 4538)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=4538, 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: "AC Input Voltage Range"
  address: 4538
  value_type: U_WORD
  unit_of_measurement: ""

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[My Inverter%203 2Kw]

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


💡 Engineer's Insight

Analysis: AC input voltage range. Units typically Volts (V). Crucial for grid compatibility and inverter protection.

Troubleshooting: Zero could indicate no AC power, loose connection, or blown fuse/breaker on the AC input side.