I’m having trouble getting my Multiplus-II out of DVCC mode. My system is a relatively simple UPS with grid-tied Multiplus, EG4 Wallmount battery, and CerboGX with Touch50 display.
I was hoping to get the EG4 BMS to control the charging by going into Multiplus DVCC mode. While DVCC mode basically works (Multiplus just does what it’s told by the EG4 BMS), I do not like the resulting charging algorithm because it never goes into Float mode but rather is stabilizes in Bulk mode after charging the battery which results in higher idle voltage on the battery than I want. It also occasionally pulses back into absorption which is unnecessary and undesirable.
When I attempt to turn off DVCC mode with the Touch50 (Settings/DVCC/DVCC), I get a warning that says, “Make sure to also reset the VE.Bus system after disabling DVCC”. I do not know how to do that, so I just reboot the GX, hoping that does it. How is the VE.Bus system reset and is this important?
Upon deactivating DVCC, the Touch 50 display indicates that the system has now gone from Ext. Control to Passthru and the “Low Battery” red LED is on. Why does it think the battery is low? If I remove grid power, the battery backup function does not work and I lose all power output. I want to get the system back the way it was before I ever fooled with DVCC mode where the charge algorithm was set by the inverter and the charge mode was displayed, Bulk, Absorption, Float, etc.
You need to turn the inverter off, then on again, with every other connected device as well.
BMS’s exist for a reason, I would not worry about that cycle, it likely will change with time and balancing anyway.
Let the battery manage itself, it can look after itself better than anything you could do.
These aren’t legacy lead batteries, so I wouldn’t worry about it.
Going against manufacturer advice and disabling DVCC isn’t likely to have a positive impact.
I have turned everything in the system off and then back on again, but to no avail.
I’m acutely aware that BMS’s exist for a reason, and I put the system into DVCC precisely for that reason, so that the battery could manage the charging, but evidently this “smart BMS” does not play well with the Victron inverter or isn’t meant to operate in this mode. The battery manufacturer recommends bulk, absorption, and float voltages which I can program into the Multiplus, which is what I originally had but then erroneously thought the BMS would do it perhaps better if I used DVCC. Using DVCC probably is going against the manufacturer’s advice and I just want to go back to the inverter control mode.
I discovered the same things. Testing DVCC and not-DVCC is quite tricky because turning DVCC off requires a VE Bus reset, and so far as I can tell there is no way to do a VE Bus reset without having a power cut, and power cuts are inconvenient (things have to be reprogammed, rest of family get grumpy).
Is there any way around this?
DVCC can be turned on without difficulty, but not off. Why is this?
I tried battery communication. I can manage charge and discharge much better for time of use and battery health.
Did you go down the bottom and disable BMS control? You can run DVCC without a controlling BMS and use it to control current from the internal charger.
