Victron MPPT 150/35 stuck in float

[ClaeTA]

I'm curious now, with the batteries being out of balance was the shunt only seeing the one battery and maybe a small segment of the other which the shunt would indicate at ~54% then once they both came into balance it sync'd to 100?

 

[sunshine_eggo]

I'm curious now, with the batteries being out of balance was the shunt only seeing the one battery and maybe a small segment of the other which the shunt would indicate at ~54% then once they both came into balance it sync'd to 100?

No. It has no clue what is connected to it beyond the numbers you program. All it sees are voltage and current. You could have 18 batteries or one, and it wouldn't know the difference.

The shunt has no idea what the state of charge is until the sync parameters are hit. The sync parameters are when the battery is fully charged. Once that is attained, the shunt sets itself to 100% and then counts the amp hours in and out continuously computing the state of charge. It will remain relatively accurate for a couple weeks but should be fully charged at least a couple times a month. More is better as that ensure the batteries are at elevated voltage long enough to do any needed cell balancing.

 

[ClaeTA]

No. It has no clue what is connected to it beyond the numbers you program. All it sees are voltage and current. You could have 18 batteries or one, and it wouldn't know the difference.

The shunt has no idea what the state of charge is until the sync parameters are hit. The sync parameters are when the battery is fully charged. Once that is attained, the shunt sets itself to 100% and then counts the amp hours in and out continuously computing the state of charge. It will remain relatively accurate for a couple weeks but should be fully charged at least a couple times a month. More is better as that ensure the batteries are at elevated voltage long enough to do any needed cell balancing.

Seeing that this is a trailer with a on board converter charger when we camp with hookups the batteries get charged, we camp every other weekend. If not then when the trailer is at our house being prepped for a trip its plugged in and charging the batteries. Is that enough?
Also is there ever a point at which you should reset the SOC?

 

[sunshine_eggo]

Seeing that this is a trailer with a on board converter charger when we camp with hookups the batteries get charged, we camp every other weekend. If not then when the trailer is at our house being prepped for a trip its plugged in and charging the batteries. Is that enough?
Also is there ever a point at which you should reset the SOC?

I can't say for certain with your batteries, but I would expect that if the batteries are at or above 13.8V for 2+ hours per month, I would expect that would be sufficient to avoid the BMS induced voltage spikes. A single full charge to 14.4V should re-sync the shunt.

When the shunt syncs to 100%, it's effectively resetting itself.

 

[HarryN]

Watching and learning from the process here.

So is the goal to gradually raise the battery voltage until the BMS activates and levels out the cells inside of the battery?

I assumed that this was 14.1 - 14.2 volts for a typical LiFe battery but I guess that can vary.

________

I am used to using other brands of solar charge controllers and trying to learn the tricks of dealing with V versions to see if I want to start using them or not.

 

[ClaeTA]

Watching and learning from the process here.

So is the goal to gradually raise the battery voltage until the BMS activates and levels out the cells inside of the battery?

I assumed that this was 14.1 - 14.2 volts for a typical LiFe battery but I guess that can vary.

________

I am used to using other brands of solar charge controllers and trying to learn the tricks of dealing with V versions to see if I want to start using them or not.

Harry -
My system has been running great since we were able to work through this issue. I'm actually in Livermore ( I see your in Pleasanton).
Clae

 

[HarryN]

Harry -
My system has been running great since we were able to work through this issue. I'm actually in Livermore ( I see your in Pleasanton).
Clae

What a small world. My work shop is in Livermore on Rutan Drive.