Atom S3 Lite Rs485 Modbus Register 33004: Daily Charging Energy

Technical Definition

The register Daily Charging Energy at address 33004 is used to monitor daily charging energy on the Atom S3 Lite Rs485.

• Protocol: Modbus RTU
• Data Type: U DWORD
• Unit: kWh
• 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 Daily Charging Energy (Address: 33004)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=33004, 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: "Daily Charging Energy"
  address: 33004
  value_type: U_DWORD
  unit_of_measurement: "kWh"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Atom S3 Lite Rs485]

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

💡 Engineer's Insight

Analysis: Energy charged into the battery daily (kWh). Tracks daily energy replenishment for the battery system.

Troubleshooting: Zero may mean no charging occurred today, a system reset, or a data logging fault. Check daily charging activity.