So it is important to note, that the BMS is monitoring for individual series branch low voltage per cell set-points. The CA is monitoring pack voltage. You could easily pass the low voltage set-point on a set of cells and not trigger the CA. That would be less of a concern on a lower voltage pack like the 3s and 4s batteries I use in R/C; however, could be a major issue at 24s for example. Long story short, it will not adequately protect the battery from over-discharge. Do so at your own risk. If they are of equal capacity and well balanced it should work fine, but I would not like that approach.