Growatt Inverter Serial Port Reader

Read data from a Growatt inverter serial port and periodically write it to a CSV file.

Includes a logrotate example config to compress and rotate the results CSV. Also includes an example service file to run the script as a service.

Requirements

• Python 3
• Logrotate (optional)
• Systemd (optional)

Usage

0. (Optional) Create a Python virtualenv and activate it:

   python3 -m venv env
   source env/bin/activate
   

1. Install the Python requirements:

   pip install -r requirements
   

2. Copy growatt.logrotate.dist to growatt.logrotate and growatt.service.dist to growatt.service and adjust them to your Pi's setup. Note that the script uses argparse to configure some settings. Run ./read_growatt_inverter.py --help to see a list of options to add to the service command:

   cp growatt.logrotate.dist growatt.logrotate
   cp growatt.service.dist growatt.service
   ./read_growatt_inverter.py --help
   

3. Copy growatt.logrotate to /etc/logrotate.d/growatt:

   cp growatt.logrotate /etc/logrotate.d/growatt
   

4. Copy growatt.service to /etc/systemd/system/growatt.service:

   cp growatt.service /etc/systemd/system/growatt.service
   

5. Enable the service:

   systemctl enable --now growatt
   

Notes

• Tested (v1.0) on a Raspberry Pi 2B connected to a Growatt 3000 MTL-S inverter via serial (RS232) to USB cable.
• If you want proper logging: create /var/log/growatt/growatt_reader.log and it will write logging to it.
• The script currently reads registers 0-45. According to the documentation there should be more than 45 registers, however during testing it appeared that I couldn't read more than the first 45 registers.