I have three installations (fourth one being commissioned next week) with six Mutliplus II inverters (three phase with two per phase). Each of these installations fails with a Phase master missing error almost every time the grid goes down (our dreaded "loadshedding"). I cannot replicate the problem by switching the mains breaker to the inverters off.
As a matter of interest, we are "forced" to use this configuration in Cape Town as the Quattro's are not on the City's approved list of inverters.
I have a site with six 15kVA Quattros in the same configuration (direct utility supply, not municipality) which never gives this problem. Same batteries as well, just more of them.
We have done all the latest firmware upgrades (now on 481) and this helped with some other issues we had with false overload errors, but the dreaded Phase master error persists on the event of a power failure (specifically grid failure, not just dropping the supply breaker).
Clearly there is some disturbance coming down the line when the grid goes down that the Victrons cannot handle which is of course very ironic as that is the main reason they were put in in the first place. We have now hooked up a very expensive piece of equipment to the one site to try and record what actually goes on in that split second before the grid goes off to see if I can install some kind of filter / arrestor that will shield the Victrons from whatever they cannot handle.
BUT all evidence points to a firmware / software issue in the Victron equipment since we only get this ever on the 6 inverter configuration and only on the Multis.
Anybody with this problem please let me know. I need to know if I am alone here which I find hard to believe.
My distributor who I have chosen specifically because of their experience with Victron is stumped but are coming out to physically inspect one of these sites next week. We use oversize wiring and have done about 40 sites since we started using Victron late last year and we do not have other problems so I will be (very happy) but surprised if they find something.