Blown Inverter, expert help requested

[confused]

Hello fellow off-griders,

I managed through a fit of distraction to plug a 6Kva generator into a house socket without disconnecting my Berel electronics 24v 60A EC3000 inverter.
The fuse on the inverters positive battery connection blew instantly. Having disconnected the generator and (yes) foolishly wired across the blown fuse, as I didn't have a replacement at hand, I turned the inverter back on and this time blew the fuse on the negative battery connection. Having finally found replacement fuses, not an easy thing in the boonies of Spain, they blew as well.
I did request help from Berel (a German company) but received no reply, maybe they don't speak English.
So the question to anyone technically minded or indeed qualified as an electrical engineer is, what is the most probable damage that I caused?
I had to replace the inverter, as the house is off grid but I am keen to repair the blown inverter to act as a stand-by just in case.
If I haven't provided enough information, I'll be more than pleased to provide whatever I can.
Yours hopefully
Confused

[Sunking]

Take it from an engineer, you need a new inverter. You backfed the inverter from the genny which destoyed it. Th egenny is not synced to th einverter and there was a huge difference in potential which shorted out the final output FET's inside the inverter. Don't do that again.

[confused]

Thanks for the prompt reply Sunking.
Don't do that again. Indeed! A massively expensive loss of concentration.
I take it from the tone of your reply, that the blown inverter is not repairable or not worth repairing.

Regards
Confused

Take it from an engineer, you need a new inverter. You backfed the inverter from the genny which destoyed it. Th egenny is not synced to th einverter and there was a huge difference in potential which shorted out the final output FET's inside the inverter. Don't do that again.

[Robert1234]

You've probably blown some mosefts, but that may be only the starting point. If you had the schematics, you may be able to get an electronics shop to repair it for you but they'll probably charge you $50 or so just to diagnose it. May be best to just scrap it.

They do make inverters that you can pass a genny output through so the inverter goes off-line by itself when the genny starts. Might be a good thing to look at. Forgetting to unhook the inverter will probably happen again.

[paulcheung]

You need to get one inverter that can connect the generator to it, so you won't have any trouble in the future. Look for the one that has an AC charger build in which the generator can connect to those terminals.

[confused]

Thanks for your replies.
It appears then that it is an "ex inverter" and not much good for more than scrap, indeed if I "hadn't nailed to the perch" it would be etc etc.
You are quite correct Robert, not isolating the inverter is very unlikely to happen again, unless I am extremely stupid and or win the lottery.
It was an expensive lesson learnt the hard way.
regards
Confused

[Sunking]

Thanks for your replies.
It appears then that it is an "ex inverter" and not much good for more than scrap,

Got a boat, you got a new anchor.

[ChrisOlson]

I don't know that I'd totally write that inverter off. It sort of depends on the design of it, if it's a modular unit like all the good quality off-grid inverters are here in the US. If it was a Xantrex SW/XW or Outback FX-series you just get a new FET board for it and you're up and running again. If it's one of them "shoebox" type inverters with everything on one board, then it's a little harder to fix. But I'd open it up and see if the FET's are blown in it. If they are, they're not too hard to solder new ones on the board. I know diddly about electronics and even I fixed the FET board on a Outback VFX-3524 once that had the same thing done to it.

[Mike90250]

But you have to know when to cut your losses. Replace FETS. discover the drivers are blown too. Replace drivers, retune because the drive currents are off between mfg A and Mfg B. Still dead. Replace CPU on logic board. Replace........ and so on......

[ChrisOlson]

Yeah, but I'd still open it up and take a look. I can see a lightning strike causing major damage. But I'll bet an out-of-phase hit from a generator backfeeding it just blew the FET's. And they're pretty easy to replace in most of 'em.