Hi all… trying to understand why I get “High charge current” and “High discharge current” alarms.
This system is made up of:
A solar collector of about 10kWp,
Two Victron Multiplus II 48/5000/70-48 inverters (master+slave)
Two Victron 450/100 MPPT
A Cerbo GX
Dyness battery bank with 21.6kWh total capacity, 6 modules
Every day, when batteries reach 100% SOC, I receive these alarms.
I have checked that Absorption and Float Voltages are according to Dyness manuals:
Absorption V = 53.00V
Float V = 52.50V
(these are the parameters I record with the PC app “Ve.bus quick configure” into the multipluses)
In the ESS config I also put “Sustain V” = 49V.
Trying to get rid of the alarms, I lowered these parameters progressively to:
Absorption V = 52.00V
Float V = 51.00V
However I see no change and still measure voltages over these values in the batteries, and because of that batteries are complaining. For example today I measured 53.81V over the batteries.
As I said I program these values with the “Ve.bus quick configure” app. However I also lowered these values in the MPPT config menu (thru bluetooth connection) but I think the local MPPT config does not apply because I see “External control” in the LCD displays of the MPPTs. Right?
Why the voltage over the batteries exceeds my config parameters? This will damage my batteries if not solved…
Thanks for any help!
If they happen one after the other it’s potentially the BMS that lost the plot a bit. I have seen a similar scenario on a different brand.
Especially if there aren’t any charges or discharges happening at the time.
You don’t need to reprogram as an fyi when lowering voltages of you have a gx use the voltage cap in dvcc.
The problem here is not voltage though.its current in other words amps. Mabe theybare discharging into each other?
How is the bank wired?
Thanks for your answer LX.
My battery bank is made up of 6 modules. They are connected 3+3, and following all Dyness suggestions. In each 3 module branch, the (+) cable is connected to the opposite module that has the other (-) cable: as usual in battery banks. If that’s not clear, I can draw a little schema for you.
I don’t understand well your phrase: “You don’t need to reprogram as an fyi when lowering voltages of you have a gx use the voltage cap in dvcc.”
But trying to solve the enigma in your sentence, I saw that in DVCC there is this option: “limit managed battery charge voltage” and I activated and adjusted it to 53.50V that is the maximum value that my batteries support. Is this what you are speaking about? I will see how it behaviours with this new value.
In DVCC menu I see that there is also the option to choose “controlling BMS”, I have these options: “Automatic selection”, “No BMS control” and “Dyness-L battery”. It is set to automatic selection. Is this OK?
Re programming would not have altered anything ad the batteries control the system.
DVCC is the only way to lake the system charge to a lower voltage.
If the dyness is selected then yes.
Did both the alrams happen one after the other?
Yes both alarms happen one after the other, charge/discharge. But the excess voltage observed over the batteries is consistent: it lasts several minutes.
“Re programming would not have altered anything ad the batteries control the system.” > What do you mean with this: that the voltages I program in the system (Absorption V, Float V) do not apply?
The BMS when it is connected to the GX will override this.
If you look in the battery information either on the GX or the vrm you will see what voltage and charge current the battery is requesting.
OK, then I will try to see what voltage the Dyness battery is requesting -in the remote console: “DYNESS-L Battery/Parameters/Charge Voltage Limit (CVL)”- when these alarms are shown. To catch this will take me some time. This value usually shows 53.5V.
It is usually displayed on the GX does not require a special set of knowlege to view.
If it is continuing to change thise changes are logged to the VRM and can be seen kn the bms widget for the battery on the vrm.
You can load that widget and battery alarms widget and quickly compare what is happening when.