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Esp32 Jk Pb Modbus Example Modbus Register 4120: Name sOC-100%

Technical documentation for Modbus register 4120 on Esp32 Jk Pb Modbus Example. Data type: U DWORD. Includes Python and YAML configuration examples.

January 16, 2026 3 read

Technical Definition

The register name sOC-100% at address 4120 is used to monitor name soc-100% 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 sOC-100% (Address: 4120)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=4120, 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 sOC-100%"
  address: 4120
  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: State of Charge (SoC) indication for 100%. Likely a flag or threshold value related to full charge.

Troubleshooting: Zero may indicate the battery is not at 100% or a sensor/reporting error.