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A32 Pro Modbus Register 102: S5140 Channel 3 Voltage - Shower Tank Level Sensor (on/off, capacitive proximity sensor)

Technical documentation for Modbus register 102 on A32 Pro. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register S5140 Channel 3 Voltage - Shower Tank Level Sensor (on/off, capacitive proximity sensor) at address 102 is used to monitor s5140 channel 3 voltage - shower tank level sensor (on/off, capacitive proximity sensor) on the A32 Pro.

  • Protocol: Modbus RTU
  • Data Type: U WORD
  • Unit: V
  • 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 S5140 Channel 3 Voltage - Shower Tank Level Sensor (on/off, capacitive proximity sensor) (Address: 102)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=102, 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: "S5140 Channel 3 Voltage - Shower Tank Level Sensor (on/off, capacitive proximity sensor)"
  address: 102
  value_type: U_WORD
  unit_of_measurement: "V"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[A32 Pro]

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


💡 Engineer's Insight

Analysis: Shower Tank Level Sensor (On/Off). Capacitive proximity sensor state (active/inactive).

Troubleshooting: Zero typically indicates 'empty' or inactive. Could be sensor malfunction, obstruction, or wiring fault.