Esp32 Jk Pb Modbus Example Modbus Register 4668: Name cell voltage 31

Technical Definition

The register name cell voltage 31 at address 4668 is used to monitor name cell voltage 31 on the Esp32 Jk Pb Modbus Example.

• 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 name cell voltage 31 (Address: 4668)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=4668, 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: "name cell voltage 31"
  address: 4668
  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[Esp32 Jk Pb Modbus Example]

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

💡 Engineer's Insight

Analysis: Voltage of cell 31, typically measured in Volts (V). Represents the electrochemical potential difference.

Troubleshooting: Could indicate a disconnected cell, faulty sensor, or a cell with zero potential difference.