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Config Modbus Register 16: Power (Phase C)

Technical documentation for Modbus register 16 on Config. Data type: FP32. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register Power (Phase C) at address 16 is used to monitor power (phase c) on the Config.

  • Protocol: Modbus RTU
  • Data Type: FP32
  • Unit: W
  • 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 Power (Phase C) (Address: 16)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=16, 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: "Power (Phase C)"
  address: 16
  value_type: FP32
  unit_of_measurement: "W"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

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

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


💡 Engineer's Insight

Analysis: Active power consumed by Phase C, measured in Watts (W) or Kilowatts (kW). Reflects instantaneous load on Phase C.

Troubleshooting: Zero value may indicate no load on Phase C, a blown fuse/breaker, or sensor malfunction. Verify phase connection and load.