BMS/MPPT settings help

[Tdcampbe]

Hi all. I am running into an issue where my MPPT will stop charging and go into float mode before the BMS says the battery is charged. 100a Daly Smart BMS and Victron 75|15 MPPT. I’m assuming it is a setting issue. I had a cheap BMS on the battery from battery hookup and recently (last weekend) took it out and and top balanced the pack and installed the Daly. Any help would be greatly appreciated as I haven’t changed any parameters on the Daly from factory settings and I know I need to. Thanks!

 

[sunshine_eggo]

BMS:
cell high protect to 3.65V
sum volt high protect to 14.6V
balanced open start voltage to 3.4V
balanced open volt diff to 0.02V

MPPT:
Change absorption duration from adaptive to fixed.
Enable tail current and set to 4A.

With your prior settings, the BMS would stop charging @ 14.40V.

 

[Tdcampbe]

I’ve made the changes listed above. Seemed to have helped a little. Will know more after the suns up tomorrow. Attached are screenshots of the cells in a couple different situations. First is ~100w+ and ~40w-. Second is just the 40w load with no charging.

Any other suggestions/tips? Is 14.40 absorption correct or should I increase it?

 

[sunshine_eggo]

I’ve made the changes listed above. Seemed to have helped a little. Will know more after the suns up tomorrow. Attached are screenshots of the cells in a couple different situations. First is ~100w+ and ~40w-. Second is just the 40w load with no charging.

All voltages are below 3.40V, so it's expected that their deviation be very small.

Any other suggestions/tips? Is 14.40 absorption correct or should I increase it?

No. 14.40V is 3.55V/cell. It's very easy to get LFP charged to full at that level.

when the battery hits peak voltage tomorrow, check that the BMS isn't engaging charge protection and look at the cell voltages.