I'm hanging on to both of my 12V inverters. They are not only handy for the car or SUV,
I can also use them on one of my little 12VDC PV setups.
These are fed by little 10w PV panels, but they do provide a bit of backup.
The black battery runs the bedroom LED lamp and the other is for Ham radio gear.
That 48Vdc sine-wave inverter might not be repairable.
I have not looked inside yet
I'm glad it wasn't expensive!
But, when/if I get it going again, I will not be using it for experiments..
It would be good for running small transformer power supplies, TVs etc..