Esp32 Main Meter Modbus Register 18: Sdm630 phase 1 va

Technical Definition

The register sdm630 phase 1 va at address 18 is used to monitor sdm630 phase 1 va on the Esp32 Main Meter.

• Protocol: Modbus RTU
• Data Type: FP32
• Unit: VA
• 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_phase_1_va (Address: 18)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=18, 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_phase_1_va"
  address: 18
  value_type: FP32
  unit_of_measurement: "VA"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Esp32 Main Meter]

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

💡 Engineer's Insight

Analysis: Phase 1 Apparent Power (VA). Total power (real + reactive) for Phase 1.

Troubleshooting: Check Phase 1 voltage and current inputs are accurate. Load must be connected. Sensor error is a possibility.