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%5Bssd1306%20128X32%5Denergymeter Modbus Register 84: Power Factor 2

Technical documentation for Modbus register 84 on %5Bssd1306%20128X32%5Denergymeter. Data type: U DWORD. Includes Python and YAML configuration examples.

January 16, 2026 3 read

Technical Definition

The register Power Factor 2 at address 84 is used to monitor power factor 2 on the %5Bssd1306%20128X32%5Denergymeter.

  • Protocol: Modbus RTU
  • Data Type: U DWORD
  • Unit:
  • 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 Factor 2 (Address: 84)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=84, 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 Factor 2"
  address: 84
  value_type: U_DWORD
  unit_of_measurement: ""

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[%5Bssd1306%20128X32%5Denergymeter]

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


💡 Engineer's Insight

Analysis: Power Factor for phase 2 (dimensionless). Ratio of real power to apparent power; indicates efficiency.

Troubleshooting: Zero or near-zero suggests a very light or purely reactive load, or a sensor issue. Assess connected loads.