Esp32 Main Meter Modbus Register 200: Sdm630 line 1 to line 2 volts
Technical documentation for Modbus register 200 on Esp32 Main Meter. Data type: FP32. Includes Python and YAML configuration examples.
January 16, 2026
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1 min read
Technical Definition
The register sdm630 line 1 to line 2 volts at address 200 is used to monitor sdm630 line 1 to line 2 volts on the Esp32 Main Meter.
- Protocol: Modbus RTU
- Data Type: FP32
- Unit: V
- 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_line_1_to_line_2_volts (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: "sdm630_line_1_to_line_2_volts"
address: 200
value_type: FP32
unit_of_measurement: "V"
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: Line 1 to Line 2 voltage (V). Measures phase-to-phase voltage.
Troubleshooting: Zero indicates loss of voltage or connection. Check supply and wiring.