Is there a way to see why Multiplus 12/1600/70 does not charge a Lithium NG to 14.2V? It seems to stay at 13.7V, SOC 98% and idle
Started “charging to 100%” and it charges in ABS mode (according to Multiplus), at first with a few amps but the voltage never gets above about 13.70V, now it is in idle mode from Cerbo/BMS NG but Multiplus still says ABS (external control), “charging to 100%” and SOC is 98.2% It seems to be stuck there.
If BMS is happy why does it not set SOC 100%
Another question, when BMS NG controls Multiplus, does it take over all setting values or does it just control charging or stopping charging?
Hmm, I ran into this in the BMS, is it the CVL that hold the horses?
Does the battery hold on and perform balancing?
It’s a small difference but it says “Balanced”
As ever, the information is in the manuals, please read the NG battery manual and the NG BMS manual.
The BMS controls the multiplus charge voltage.
The BMS asks for either 14.0V (absorption) or 13.7V (float). 13.7V keeps the batteries just below 100% and avoids overcharging which is good. 14.0V is required for balancing so you need some time in absorption. The manual says 2 hrs per month for lightly cycled and 8 hrs per month for heavily cycled.
The BMS has 2 settings, SOC threshold, default 70% and repeat absorption interval 30 days. You change these to suit your use. Basically, the BMS stays on float all the time unless the SOC drops below 70% or 30 days goes by since the last absorption.
You could set a daily absorption or a 90% limit. If you have more frequent absorption then you need to reduce the absorption time from 2 hrs to 15 min for daily absorption.
Personally I am happy with the way NG works, I think it is much better if you are not cycling a lot to stay just below 100% rather than overcharge them.
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Thanks for the clarifications 
Many of us read the manuals both forward and backwards but despite that, scenarios arise where different things depend on each other and it is difficult to see through when different products should talk to each other and the display don´t show what you expecting. All these variants are not always covered by manuals and you need to get some support from outside.
So, I completely agree with your reasoning and of course you want to take care of your batteries, what confuses this is that you make the choice “charge to 100%”, Multiplus starts charging in ABS mode and stops in that position because the BMS in the background sets the CVL to 13.7V and you experience that the charging is slowing down.
It is perceived as confusing, Multiplus is in ABS mode but is only allowed to charge 13.7V which from the BMS point of view is Float mode, it is not clear that BMS “asks” for Float and gets Float from Multiplus (apart from the voltage), it gets Float in ABS mode from the Multiplus, confusing…
VRM reports that the choice “charge to 100%” remains, while the charge control says “Idle” and the current is 0A.
I am wondering if one should take more notice of the fact that e.g. MutliPlus shows “External Control” (MTTP also shows it) due to DVCC and that then one should look deeper into why it behaves in a certain way even if one thinks it should behave differently.
At the same time, I think that if I have chosen to activate “charge to 100%” it should override what BMS thinks and charge up to 14.2V and set SOC 100%
