Hi,
In three months I have had two Victron Multiplus II GX 3000/48 that has failed on me. The first had issues from day one and was in my opinion clearly faulty out of the box and was quickly replaced. Thank you Victron.
The second time I have issues the dealer says it is unlike that two units would fail, and that there is "something" wrong with my battery setup, causing the Victrons to fail.
I use four Tesla model S modules and they have a max voltage of about 49 V. I have a BMS monitoring the battery and disconnects the pack if the voltage go higher than 49 V or lower than 37 V. It has never disconnected the battery as I have put the limits in the Victron to stop charge at 48 V and stop discharge at 42 V.
This unit is used for battery backup only, meaning I have not activated ESS. It is connected to the grid via ac in, and the important equipment is connected to ac out. I have tried it a few times by disconnecting ac in and let it run on battery for some hours to ensure everything is working. When I reconnect ac in the battery is charged to 48 V.
Regarding my now failed second unit the dealer says "Tesla used cells are very low voltage settings difficult work on victron, the 46V in Multiplus is only the shutdown voltage level for the inverter." I have asked for documentation supporting this claim, but so far I have not received anything. From what I have read, the inverter limit is 37.2 V, not 46 V. Does anyone here know what this 46 V limit is about?
Anyway, the problem I have is that the Victron (after running smoothly for two weeks) suddenly refuses to charge the battery regardless of what I try. I have updated firmware to 2.60 and reset everything using VE config, but this does not resolve my problems. I have even connected a 48 V led battery to the Victron to exclude a faulty battery setup, but the problem is still there.
If I run it in mode 1 (on) the inverter starts, and drains the battery saying "no ac in" even though ac in is connected. I can also read ac in voltage and frequency on the small screen (230 V and 50 hz, which is normal). If I disconnect the battery the Victron continues to provide power from ac in to ac out. It says "HUB-3 passthru" on the small screen. I can't make it switch to charging batteries regardless of what I try.
If I run it in mode 2 (charger only) it also says "HUB-3 passthru". It never starts charging. I have tried to manually start "equalization" via the remote panel. I then get the message "charger not ready".
I would be very happy if someone here could help with this issue. The dealer refuse to take it in for repairs unless I pay for it, claiming faulty batteries as the source of trouble.
Thanks,
-M