Esp%20Inverter Modbus Register 74: Friendly name Total Battery Discharge (kWh)

Technical Definition

The register friendly name Total Battery Discharge (kWh) at address 74 is used to monitor friendly name total battery discharge (kwh) on the Esp%20Inverter.

• Protocol: Modbus RTU
• Data Type: U DWORD R
• 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 friendly_name Total Battery Discharge (kWh) (Address: 74)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=74, 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: "friendly_name Total Battery Discharge (kWh)"
  address: 74
  value_type: U_DWORD_R
  unit_of_measurement: "kWh"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Esp%20Inverter]

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

💡 Engineer's Insight

Analysis: Total energy discharged from the battery (kWh). Indicates battery usage for loads.

Troubleshooting: Zero reading may mean the battery was not used, or a sensor/communication fault exists.