I have a multiplus 120V 2k model, a 48v battery, and a shunt. (and a cerbo)
I’m having trouble getting the display to work how I want.
I have it wired up with the battery - going to the ‘loads’ side of the shunt, and battery - on shunt to the battery. + connected directly. I have DC power being pulled from the shunt load - and battery + directly.
I have the cerbo configured with ‘has DC system’ . This gives me this diagram. However, some things don’t make sense and/or are wrong.
The grid isn’t powering anymore, notice the drop at the right of the graph (I just changed wiring), and no lines for power going from grid to victron.
The battery shows discharging into the multiplus and to the DC power. And a 3W AC load.
The 40W should be more like 60W, I’m drawing that much on the DC side so I have this reporting error, plus the grid isn’t flowing and I would expect that the power flows from grid through to the DC power.
The battery negative NEEDS to go the the Battery side of the shunt, If the Shunt is being used for DC loads, then those loads connect to the shunt, and the inverter connects to the battery -ve (All Positive connections are common & fused).
If the Shunt is monitoring total battery, then the inverter negative goes to the shunt load side too.
Treat the battery negative to Shunt ‘Battery’ connection as an active line, it must not be grounded.
The reason the charging stops, is that discharging the battery with the shunt connected backwards raises the soc instead of lowering it.
Your description of the shunt wiring is hard to understand. The battery negative goes to the battery side of the shunt and is the only cable on the battery and that side of the shunt. Everything else goes on the load/system side of the shunt. This is for battery monitoring.
In terms of has DC system, do you in fact have chargers and/ or DC loads. This FAQ explains about the vageries of has DC system, it will count things like idle current for the inverter, Cerbo GX etc.
To get an accurate value here needs a SmartShunt used as a DC energy meter.
The “Battery Charged Voltage” in the shunt is nothing to do with setting the charging voltage, it is not a control setting, it is a monitoring setting and is there to monitor when the battery is full so the shunt knows it should be reading 100% when the voltage gets to this value. The battery charging settings are in the Multiplus. Have you been doing firmware upgrades on the Multiplus because if you have been doing stuff in there then sometimes the upgrade procedure sets the absorption voltage to 48V and you have to go back in manually and set it to the correct charging voltage.
ok, I was already on that track. it did update my absorbtion values on a firmware update. the newest version of VE configure was refusing to write the dang file via wine on mac so I had to run an older version.
Is this ‘issue’ reseting those values a known thing that is solved or should I expect this with every update?
FWIW, it’s working now. AC load is a fan I plugged into inverter just to force the grid to pull some power. The shunt is showing reasonably accurate numbers now also.
Every time you do a remote firmware update it downloads the settings file, which has to be updated and uploaded back again.
From another recent post about not charging after remote firmware update.
Read the instructions at.
You need VE Configure running on Windows. During the update via VRM the settings are downloaded automatically. The downloaded file
Then needs to be opened in VE Configure, converted, checked and reuploaded.
Extract from the manual.
After the firmware update is completed, the inverter is switched on again. The settings will have been reset to their defaults. And, to prevent overcharging, all charge voltages have been set to the nominal battery voltage, being 12V, 24V or 48V. This effectively disables the charger.
