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Heatpump Modbus Register 200: Entity prefix Home Appliance Type

Technical documentation for Modbus register 200 on heatpump. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 3 read

Technical Definition

The register entity prefix Home Appliance Type at address 200 is used to monitor entity prefix home appliance type on the heatpump.

  • 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 entity_prefix Home Appliance Type (Address: 200)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=200, 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: "entity_prefix Home Appliance Type"
  address: 200
  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[heatpump]

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


💡 Engineer's Insight

Analysis: Register 200 (bits 0-7): Identifies the specific type of home appliance (e.g., Heat Pump).

Troubleshooting: Incorrect or null value suggests configuration error or device identification failure.