Hi,
I've installed 6 Quattros 10kVA 3-phase | 2 per phase in parallel.
I commissioned the system about 6 month ago and it was working fine with no problem.
since 2 month ago Genset MCB started tripping occasionally BUT after a couple of weeks they don'
t stay on and trip as soon as genset wants to kick-in.
I'm confused because this has happened slowly and getting worse and worse.
I also found this black marks on one of my inverters (Phase3-2'nd Quattro)
Smoke on the neutral? Nice one.
Sounds like the breaker was doing its job.
Looks like you have some more investigation in the set up. Hopefully haven't left it too long.
It will be getting worse as the problem (possibly arcing) is getting worse. Chances are the mcb is getting hot as well, and will need to be replaced.
What is the current sharing like between units? That may be a bad crimp combined with not so great current share because of oversized conductors on the parrallel....
I suggest you to shutdown the system and verify the crimping on the black cable.
It looks to me as it was overheating on the bottom.
Do you use 230/400V system?
How big are the cables?
The AC out should now be under 10mm².
Better use 16mm² or if you use pass-trough even 25mm².
Note: I use already 16mm² on my MultiPlus-II 25/5000 since I have plans to stay with 230V but wunt to add in end of the year a second one and in Summer 2024 a third one.
the cable size is 10mm²
system size (Quattro 10kVA - three phase system - 2 per phase in parallel)
I'm more suspected of the ground relay not sure if the generator can make neutral/Earth unbalance however MY earthing system is NTC-S
