EmsTechLabs Logo EmsTechLabs

Sensors Modbus Register 10: Open Time Hours

Technical documentation for Modbus register 10 on Sensors. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 3 read

Technical Definition

The register Open Time Hours at address 10 is used to monitor open time hours on the Sensors.

  • Protocol: Modbus RTU
  • Data Type: U WORD
  • Unit: Hours
  • 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 Open Time Hours (Address: 10)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=10, 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: "Open Time Hours"
  address: 10
  value_type: U_WORD
  unit_of_measurement: "Hours"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

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

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


💡 Engineer's Insight

Analysis: Represents the 'Open Time' duration in hours. Indicates how long a device or process has been active or open, measured in hours.

Troubleshooting: Zero indicates the process hasn't been open or active for any full hours. Check if the device is functioning correctly or if the timer has been reset.