Modbus Modbus Register 342: SDM630 Total

Technical Definition

The register SDM630 Total at address 342 is used to monitor sdm630 total on the Modbus.

• Protocol: Modbus RTU
• Data Type: FP32
• Unit: kWh
• 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 SDM630 Total (Address: 342)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=342, 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: "SDM630 Total"
  address: 342
  value_type: FP32
  unit_of_measurement: "kWh"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

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

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

💡 Engineer's Insight

Analysis: SDM630 Total value. Likely total power or energy, context needed. Units may vary (kW, kWh).

Troubleshooting: Zero suggests no load, meter fault, or configuration error. Confirm meter settings and power flow.