But when my battery is âfullâ - preferable by me SOC 98% my battery is all the time charged and discharged.
Battery all the time has ~150w discharge, ~150w charge. And all the time.
Make sure the GX is on the latest version.
Your BMS spoofs Pylontech, it is not pylontech though and is ultimately unsupported. So if current GX firmware doesnât help, you may need to speak to that manufacturer or use a conventional BMV instead.
Yes, this is similar problem to mine.
But without solutions In every threads example solutions is BMV, but without continuation and answers: yes, itâs works.
Probably I have to buy smart shunt and try that solutions.
Hi iâm pretty sure it is not the BMS, the BMS is only there for protection it should not regulated the charge/discharge cycles. The BMS should only intervene when the limits are exceeded of battery gets to hot/cold.
But I did some testing without BMS/With BMS/ With DVCC and Without DVCC see picture below.
(in the middle the BMS is connected again and the CVL rises it goes from float to absorption mode)
There are some variations time wise but the battery still is charging/discharging when full and more then enough PV power. When you put it in charger only with keep batteries charged it does not have that behaviour but the Multiplus goes to idle mode. I think it is just how the control is designed in the victron system only thing is that not everybody is seeing it.
If your BMS isnât setting the CCL to 0A when the battery is at 100% then the DVCC controlled chargers are going to try and charge the battery. The BMS is telling the system âI will accept charge currentâ.
The BMS is regulating charging, it controls the whole system via DVCC. If it is not configured correctly the system will behave in undesirable ways.
If battery voltage is allowed to creep up beyond where it should be, the system will discharge it. Why it creeps up is usually all about how the battery is configured.
This is one of the joys of DIY batteries.
Battery has SOC 100%, stable voltage ~56,8V, no charging and discharging. BMS set CCL to 0A.
Probably it works good, because Victron doesnât try maximizing of production from PV and voltage on whole DC system is stable.
After a few hours I enable export to the grid.
After that export start, but charging and discharging too.
I have one more idea. When I turn on DVCC and export to the grid, System add 0.4V to the voltage limit. With this configuration on MPPT I have 57,2V instead of 56,8V.
Today Iâll try again, but after stabilize system on 56,8V and turn on export, Iâll setup voltage limit to 56,4V (56,8V on mppt like whole system)
The DVCC voltage limit is not intended for ongoing use, setting it the same as the battery will have zero effect.
Export raises the voltage by 0.4V, that is by design else exporting wonât happen, and it will ignore anything you set to prevent it happening. The inverter will drive this offset down under load, so once stable it shouldnât be an issue for a battery and it is something that supported batteries are tested for.
On my own I can see an initial fluctuation once the inverter/mppt tug of war starts, but it settles soon enough.
In every threads example solutions is BMV, but without continuation and answers: yes, itâs works.
