Esp32 Jk Pb Modbus Example Modbus Register 4104: Name cell UVPR

Technical Definition

The register name cell UVPR at address 4104 is used to monitor name cell uvpr on the Esp32 Jk Pb Modbus Example.

• Protocol: Modbus RTU
• Data Type: U DWORD
• 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 UVPR (Address: 4104)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=4104, 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 UVPR"
  address: 4104
  value_type: U_DWORD
  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: Cell Undervoltage Protection Reset (UVPR) status. Indicates if the UVP fault condition has been reset.

Troubleshooting: Zero means UVP is active or has not been reset. A non-zero value indicates a reset condition.