mchiriciuc

Regarding the F80 error (you are right it is CAN bus comms failure) I had two inverters in parallel operation which started to throw this error gradually (like 6 months no error and then it started to appear more often) without any change in cabling and/or software settings with the same firmware they came from factory. When throwing an F80 error, the inverters went to bypass and stop working in parallel (this should be normal it avoids the risk of them working out of phase).
I also suspect a hardware failure on the parallel boards because in standalone operation there is no error whatsoever (parallel boards still installed). 
It seems that there is a component regarding to CAN comms that is gradually deteriorating. Maybe the opto-isolators, or maybe a faulty capacitor on the opto's supply line and too much noise on the rail which can also lead to comms problems. It's winter here and I have no means of investigating this further at the time. Will try to hook up my oscilloscope to the parallel board in spring/summer to see what is going on on this boards.
It may also have something to do with induced noise in the paralele cables. Extra shielding them seemed to improve it a bit. 
Does anyone has the schematics for the parallel boards and the CAN comms circuitry from there to the controller?