Modbus M11 Merged Modbus Register 8448: Motor Status

Technical Definition

The register Motor Status at address 8448 is used to monitor motor status on the Modbus M11 Merged.

• Protocol: Modbus RTU
• Data Type: U WORD
• 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 Motor Status (Address: 8448)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=8448, 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: "Motor Status"
  address: 8448
  value_type: U_WORD
  unit_of_measurement: ""

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Modbus M11 Merged]

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

💡 Engineer's Insight

Analysis: Indicates the operational state of the motor (e.g., running, stopped, fault). Essential for monitoring motor health.

Troubleshooting: 0 (or a specific fault code) could mean the motor is off, has experienced a protective trip, or has a wiring/control issue.