The chip is useful, but requires simple manipulations to disassemble the inverter and the refrigerator. After seeing how this is done, it will not be scary at all. As a result, you do not feed the inverter idle around the clock, reducing energy consumption.
The proposed option for connecting to alternative sources is more energy-efficient, simpler and cheaper than an inverter with a sleep mode.
How to choose an inverter?
How to install an inverter?