I have a 3-phase system with MPII 5kVA inverters and (currently) three Pylontech US5000 batteries. All electrical systems in my home are connected to the MPII ‘Essential Load’ outputs. The Victron ESS Assistant makes sure that energy from my PV system is first used to charge the batteries, excess power is fed in the grid. I use the ESS control setting ‘Optimized with BatteryLife’, which works fine in a normal situation.
However, I don’t know what I should do if I want to quickly charge my batteries without considering the PV generation. Let’s say that I want to have my empty batteries fully charged as quickly as possible because of a planned grid outage, how should I do that ?
If I change the ESS control setting ‘Optimized with BatteryLife’ to ‘Keep batteries charged’, I noticed that only one MPII starts charging the batteries with full power (directly from the grid). So that’s probably not the way to do it. Right after commissioning my system and before I installed the Victron ESS Assistant, I had the three MPIIs charge the Pylontech batteries with full power (~240A, 80A per battery). So know that all inverters work fine.
There should be a better way to do this than removing the ESS Assistant. All help would be much appreciated.
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
2
Go into ESS settings on your GX device and change the Minimum SOC value to 100%. I just did this and tested it to get you the screenshot below.
@OGPS I just noticed that the status of my batteries has been ‘Idle’ since reverting to my original minimum SOC setting (20%). This means that the grid is used instead of discharging my batteries to power my home. The batteries are currently 39% charged, so higher than 20%.
Should I do anything else to restore my original situation ?
BTW: the ESS ‘Battery life state’ is ‘discharge disabled’. That’s probably a bug in the victron software as the SOC is 39% with a lower limit of 20%.
OGPS
(Ed @ Off-Grid Power Systems - offgridps.com)
6
I don’t run my ESS system with BatteryLife enabled. Read chapter 6 of the ESS manual as it (tries to) explain what using BatteryLife vs not means and how it dynamically adjusts the SoC cutoff point and uses your defined set point as a starting point. If you leave the system along for a week or so it may adjust itself back to a baseline. You can also try running Optimized without BatteryLife. It will operate closer to your defined SoC setpoint, but it can still deviate a bit.
If you want the ESS algorithm to dynamically determine the right SoC cutoff point on its own then leave it alone. If you have a stable grid with short outages, then run w/o BatteryLife and set your SoC as low as you’re comfortable using.
I’m using Pytes batteries that do an excellent job of maintaining cell balance at the top or bottom of their charge cycle so I run without BatteryLife. I don’t have experience with Pylontech so I can’t advise you on the “right” setting to choose. But, if I were you, I’d run without BatteryLife for a while and keep an eye on your battery cell balance at the top and bottom of their cycles and see how they do.
Maybe someone more experienced with ESS and Pylontech batteries can assist here.
