Deye12 Modbus Register 541: Sun12k-Heat sink Temperature

Technical Definition

The register sun12k-Heat sink Temperature at address 541 is used to monitor sun12k-heat sink Temperature on the Deye12.

• Protocol: Modbus RTU
• Data Type: S WORD
• Unit: °C
• 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 sun12k-Heat sink temperature (Address: 541)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=541, 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: "sun12k-Heat sink temperature"
  address: 541
  value_type: S_WORD
  unit_of_measurement: "°C"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Deye12]

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

💡 Engineer's Insight

Analysis: Temperature of the inverter's heatsink. Units: Degrees Celsius (°C).

Troubleshooting: A value of 0 or unexpected readings could indicate a faulty Temperature sensor or inadequate cooling.