peak cut should set as 12 and it still cut off then that indicate your battery was not in a good condition, if you set it to 99 will damage your battery very fast, better go to the much more site to learn more about the delta peak.
I use parallel pack. so i discharge each individual cell to 0.9V by 10A.
then charge the whole pack to 3000mah by 5A.
then peak each individual cell with 0 Delta peak.
so I can tell if there is any problem with each cell.
just found one intellect cell is dead. need to be replaced.