I will shortly explain my setup:
I have a Victron MP-II 5kW inverter with 2x 16xLiFePo EVE 280 batterypack. Each pack is controlled with a cellmate-k9, together with a smart shunt and Watchmon core. The Watchmon is connected to a Cerbo GX.
The MP-II is connected to phase 1 of a 3 phase system.
Two AC PV-inverters are connected to the main supply. One on phase 1 and one on phase 2.
A third PV-controller (Victron SmartSolar) is connected to the DC-bus of the Victron MP-2.
The AC PV-inverters are just producing and not controlled. Any excess of solar power is fed into the grid.
The Victron SmartSolar is connected to the Victron Cerbo. A main power meter (3-phase) is also connected to the Victron Cerbo.
The system is configured for ESS and DVCC is forced ON. SYS is forced ON and STS is forced OFF, controlling BMS is Batrium.
Observation:
Before the SmartSolar was added to the DC-bus, I noticed that the system was able to keep the sum of total power of all 3 phases at 0W with less to moderate sunshine. There are some power swings due to the reaction time of the Victron inverter, but acceptable.
But now the SmartSolar is added to the system low SOC (ESS#1 and ESS#2) is active, I do see more power going into the grid than charging the battery. Currents are fairly low at this moment (winter time Holland).
Are there settings in the SmartSolar that affects the proper operation of the ESS-function? If yes, how are these settings related to the voltage settings of the Batrium system (CV-values)?
So what do I need to set for float and absorption voltage?
Hi,
you’re mentioning a “smart shunt”. Just guessing by the name, is this a Victron Smart Shunt? If yes, you should replace that with a Batrium ShuntMon. Otherwise, your Victron system might get confused to have Batrium as the controlling BMS and a Victron Smart Shunt for the SoC.
Second, ESS state #2 is due to you configuring ESS mode “optimized with battery life”. “Battery life” is only necessary for some battery chemistries, it is not necessary for LFP cells. You should switch to ESS mode “optimized without battery life”.
And to finally answer your question: The ESS state #1 means, inverter in the MultiPlus is switched off. This is indicated by the inverter LED being turned off. Since installing the solar charger, it is preferred to charge the battery before utilizing the MultiPlus to charge the battery from AC PV excess. The parasitic losses are way fewer when charging a battery from DC coupled PV. A certain threshold of AC PV excess is required to turn charging from AC coupled PV back on. This results then in grid power to fluctuate more than you expect. This changes instantly, when ESS state #1 turns off.
Kind regards,
Marcus
Thanks for the reply. I have a Batrium shunt and I have switched of the optimized with battery life as suggested.
But I do not understand the last section regarding the PV-systems. ESS#1 is low SOC. To me, this is a normal operating condition. The location/setup of the DC-coupled PV is more shaded, and start producing at a later stage than the AC-systems.
Is there something I can optimise in voltage settings of either Batrium of SmartSolar?
I doubt there is anything you can optimize in settings of Batrium or the solar charger. The solar charger voltages are completely remote controlled through DVCC.
Best would be, you present in detail, what you feel uncomfortable with. You’re saying, more power is flowing to the grid, than to the battery. How much power are both? And what are current battery voltage and by Batrium reported CVL, CCL, DCL to the Victron system?
@kleini Thank you Marcus for your wise words on Victron! Everything you mentioned lines up with our understanding too.
Hi John,
Thanks for posting! Since you mentioned trying to catch the right moment, you will probably want to make sure your device is provisioned to VRM (Victron, just connect to the internet) and BMI (Batrium, guide).
After that, you can private message me your WatchMonCORE serial number, and if you want, a read-only VRM link.
Kleini is pretty much spot on with the comment that while your Batrium system can set limits, we don’t force the Victron system to do anything, and ESS settings are the usual place to look.
