huawei-solar 3.0.2

A Python wrapper for the Huawei Inverter modbus TCP API

Python library for connecting to Huawei SUN2000 Inverters over Modbus

This library implements an easy to use interface to locally connect to Huawei Solar devices over Modbus-TCP or Modbus-RTU following the 'Solar Inverter Modbus Interface Definitions' provided by Huawei.

It was primarily developed to add support for Huawei Solar inverters to Home Assistant, resulting in the following integration: wlcrs/huawei_solar.

Supported devices:

• SUN2000 inverters
• LUNA2000 batteries (when connected to SUN2000)
• EMMA
• SCharger (when connected to EMMA)

Features:

• Modbus-TCP support: connecting to the inverter via the SDongle, EMMA, or over the WiFi-AP (SUN2000-<serial_no>) broadcasted by the inverter
• Modbus-RTU support: connecting to the inverter via the RS485A1 and RS485B1 pins on the COM port
• Batched reading of Modbus registers and converting them into the correct units
• Reading Optimizer data via the specialized 'file' Modbus extension
• Writing to Modbus registers (mostly useful for setting battery parameters)
• Performing the login sequence to gain 'installer'-level access rights

Installation

This library is published on PyPI.

Basic usage

The library consists out of a low level interface implemented in modbus_client.py which implements all the Modbus-operations, and a high level interface in huawei_solar/devices which facilitates easy usage (primarily meant for the HA integration).

Using the high level 'Devices' interface

An example on how to read the most interesting registers from the inverter:

import asyncio

from huawei_solar import (
    SUN2000Device,
    create_device_instance,
    create_tcp_client,
)
from huawei_solar import register_names as rn

async def test() -> None:
    """Run test."""
    client = create_tcp_client(host="192.168.1.1", port=503)
    device = await create_device_instance(client)

    assert isinstance(device, SUN2000Device)
    print(
        await device.batch_update(
            [
              rn.INPUT_POWER,
              rn.LINE_VOLTAGE_A_B,
              rn.LINE_VOLTAGE_B_C,
              rn.LINE_VOLTAGE_C_A,
            ]
        ),
    )

if __name__ == "__main__":
    asyncio.run(main())

This results in the following output being printed:

{'input_power': Result(value=82, unit='W'), 'line_voltage_A_B': Result(value=233.4, unit='V'), 'line_voltage_B_C': Result(value=0.0, unit='V'), 'line_voltage_C_A': Result(value=0.0, unit='V')}

Frequently asked questions

Q: the connection is interrupted a few seconds after connecting to the Huawei Device. How do I solve this?

A:: Huawei devices only support one connection at a time. If your connection is interrupted, this is typically because another device is trying to (re-)connect to it. Disable that device and try again.

Acknowledgements

The initial implementation of v1 was done by @Emilv2.

Subsequent development on v2 was done by @wlcrs.