I have an off-grid system with a Multiplus 24/5000, MPPT 100/35 and a fronius primo 3.0 on the ac out. After the batteries have charged at 100% and the absorption is finished, they begin to slightly discharge althoug there is a lot of solar power to manage the loads and keep them charged. In detail the mppt 100/35 turns of and does not provide power.
The system is working with an ess assistant with "keep batteries charged" enabled. Any ideas?
I’ll venture a guess, based on my SmartSolar‘s behavior. The charge controller will go to float (if so programmed) once it meet the set voltage cut off. The battery will begin to settle to a lower voltage, which is normal. The charge will not resume until enough energy is used to return to bulk charging.
One thing I did find was that my SCC was set to “Adaptive” for absorption charge. I noticed this to normally cut off in 10 minutes, and rarely go to 17 minutes. This never took my battery bank to the 28.8 volts it was set for. After consulting with BattleBorn for recommendations, I reset this to a fixed 60 minutes. This brought my batteries to full charge. They will, of course still settle to a lower voltage, but it was a higher number corresponding to the extra charge time. Not a perfect solution to your question, but sometging to check.
Thank you for your reply!
My mppt is coontrolled by the ESS and is marked with the "external control" status. So i am not sure if any changes made to it will help. I will try to change the adaptive to fixed and see how it goes.
Thank you again!
Hi @vbelijohn ESS is not for use on off-grid systems so you may want to consider uninstalling it.
Uninstalling is not possible. I use OPZS batteries and using the cut-off voltage provided on ess is more than helpful. I also occasionally connect to the grid.
