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Schundmeter Modbus Register 366: Chint reactive power phase 2

Technical documentation for Modbus register 366 on Schundmeter. Data type: S DWORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register chint reactive power phase 2 at address 366 is used to monitor chint reactive power phase 2 on the Schundmeter.

  • Protocol: Modbus RTU
  • Data Type: S DWORD
  • Unit: VAR
  • 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 chint reactive power phase 2 (Address: 366)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=366, 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: "chint reactive power phase 2"
  address: 366
  value_type: S_DWORD
  unit_of_measurement: "VAR"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

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

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


💡 Engineer's Insight

Analysis: Reactive power for phase 2 (kVAr). Indicates energy oscillating between source and load, not doing work.

Troubleshooting: Zero if load is purely resistive or if phase 2 is disconnected. Abnormal values may indicate poor power factor or equipment issues.