Hi, first i need to explain my installation. I have an MP2 ac-coupling mode. I have not mppts or any dc charger connected to my battery. No ac in loads, all loads in ac out. And several microinverters in ac out. The charge of the battery is made by MP2 ac/dc charger with the energy generated by microinverters (not more than 2.5kW). ESS assistant configured. BAttery has bms but NOT communicated. The “battery monitor” responsible is an smartshunt (300A version). Battery is 15kWh one. (big enought)
ESS is configured to charge up to 55.2v
As I am out of house for several weeks, just before goint out I configured the DVCC activating the “limit managed battery charge voltage” to 53.6v
But… it is not limiting that, at least all days.
Here you have the day before yesterday graph. (I will put more graphs afterwards)
DVCC allows the battery BMS to control the voltages. When no compatible battery BMS is present the inverter/charger (your multiplus) provides the charge settings. See the manual.
But I dont agree with your apreciation about DVCC. In manual, as you has linked it, you can see this under 12. DVCC - Distributed Voltage and Current Control (12.4 **DVCC features for all systems) ,**that is “independent” of a battery with or without communication, this paragraph:
12.4.2. Limit managed battery charge voltage
Some managed batteries, such as BYD and Pylontech, may require a reduced charge voltage during their initial commissioning period. This helps ensure proper cell balancing in the first few weeks of operation.
The Limit managed battery charge voltage feature is designed specifically for this purpose.
When enabled, it allows to temporarily reduce the maximum charge voltage, even if the battery’s BMS normally permits a higher voltage.
As we can read, “limit managed battery charge voltage” is just to limit the charge voltage.
What I am doing, as I am not in house now, is to avoid that my battery goes to absortion every day. There is not need to do that if your power consumption is too low. Better battery life.
Besides, if this doesnt work …. why it is working some days and not all days? I think there must be another algorithm variable that I don’t know. May be anyone from Victron support team could clear this.
See this last days graph. Some days it is limited to 53.6v (just the value I have configured in DVCC) and some other days, Victron decides to charge it up to 55.2v
I am not sure, but then…. why it is limiting some days and other days…. not ? (I have enough solar energy because i am exporting all these days that I am not at home. It is clear in graphs that DVCC is limiting to 53.6v some days.
I want to find a “quick” solution to limit charge voltages during my travels, changing the configuration to the MP2 directly is … a lot of work. I hope someone from victron could read this post.
Just to test more, I have just change in remote console from 53.6 to 54v as limit charge voltage. I will see next days’ graphs
“Limit managed battery charge voltage” only applies to managed batteries, i.e. batteries that communicate with the GX device where the BMS controls the voltage, this setting allows you to set a lower charge voltage than the BMS. You do not have a managed battery.
You may be able to do this type of thing with Node-RED, you may be able to write the absorption voltage to the Multiplus.
Another option is the GX device can now store a backup copies of the Multiplus settings. What you do is save a backup copy with full voltage, then adjust the Multiplus to the lower voltage then save a second backup copy with another name. Then you only need to restore the alternate backup settings. If you do this, then you will need to keep the Multiplus firmware constant as a firmware upgrade may change the available settings needing new back up files.
