Hi I have installed 2 x 48v 200A Rosen LiFePo4 Lithium Batteries (Pylontech clones) which is a total of 20Kw of battery storage.
I have based the RS 450/100 MPPT TR charge controller and Victron assistant ESS (I am still grid connected to be able to draw from it at night when its cheaper if I need to) within the MultiPlus charging configurations on 15 cell maths (because my packs are 15 cell packs).
Above is the MMPT charging config
Above is the MultiPlus configuration.
I am running the Victron ESS assistant on the MultiPlus so I can send and draw power to and from the Grid.
The Issue I am having is that in since turning the batteries on and adding the House load (all on the Critical side of the inverters AC out, I have no loads on the grid side of the system). If I then turn off the Grid, and turn off the solar panels, so that only the Batteries are powering my home, which simulates after sundown usage. While switching between the various power sources is seamless. When we are on only battery. The MultiPlus throws a low battery alarm and turns itself off when the Batteries get drawn down to 99% SOC. You either have to switch the grid back on or the solar panels to have the batteries increase their SOC, at which point the Multiplus resets and all is good again.
I must have set something in the MultiPlus' configuration to not allow enough draw from the batteries.
Can anyone point me in the right direction to setting the correct parameters to allow the batteries to be drawn down to 25% or 30% SOC before the inverter switches off.
Kind regards
Duncan
