I have just got the above battery combiner and found that the stated voltages in the documentation to be inaccurate.
It states that the unit will combine the batteries if the voltage is 13.7v or more on either terminal. I've done serveral tests with the use of 3 multimeters and the BMV 712 battery monitor installed and the unit is engaging when the batteries are at just 13.3 V.
Also, something I didn't think about, but the 13.2 V disconnection, in my opinion, is too low. My lithiums sit at around 13.2 V and once connected both they and the starter battery stays that way unless I place a heavy load on it dropping the lithiums and said starter battery down below 13 V. I would have thought that having the disconnection set at 13.4 V would make more sense and give a disconnection once any charging source has been removed.
I'll live with the issues, but does spoil what could be a brilliant device as I feel all my other Victron products are (MultiPlus, Venus GX, Isolator Transformer, BMV 712, Battery Protects...)
If I'm missing something here then please let me know as I hope I'm wrong and can get this functioning as originally intended.