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Bms Sensors Pace Rs485 Bms Full Modbus Register 31: Battery Temperature 1

Technical documentation for Modbus register 31 on Bms Sensors Pace Rs485 Bms Full. Data type: S WORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register battery Temperature 1 at address 31 is used to monitor battery Temperature 1 on the Bms Sensors Pace Rs485 Bms Full.

  • Protocol: Modbus RTU
  • Data Type: S WORD
  • Unit: ˚C
  • 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 battery temperature 1 (Address: 31)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=31, 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: "battery temperature 1"
  address: 31
  value_type: S_WORD
  unit_of_measurement: "˚C"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Bms Sensors Pace Rs485 Bms Full]

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


💡 Engineer's Insight

Analysis: Temperature of the first battery pack/section (°C). Crucial for thermal management and safety.

Troubleshooting: Sensor failure or poor thermal contact. Verify sensor wiring and mounting.