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david-prentice asked

Battery not charging above 54v

I have system that will not charge the battery above 54v. Both the MPPT and charger settinga are set to 56v (absorption) , 55.5v (float).
I've tested the settings with running charge for many hours and tested the MPPT. At the moment I am unsure if the problem resides in the Victron of the Daly BMS?

MultiPlus-II 48/5000/70-48
Cerbo GX
SmartShunt 500A
SmartSolar Charger MPPT 150/35
Daly 16S BMS - LifePo4 Eve cells


I have checked the settings in VE Configure and the MPPT (VEconnect). is there any thing i can try to get a higher charge voltage?



Multiplus-IIMPPT SmartSolar
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JohnC avatar image JohnC ♦ commented ·
@David Prentice

Is your battery still accepting current?

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david-prentice avatar image david-prentice JohnC ♦ commented ·
Yes, the battery is charging with no problem. It always flatlines at 54v when charging for the DC alternator, MPPT, or shore power. It has never gone above a charge of 54v since install.


VE Configure Charger settings:

Charge curve: fixed

Absorption: 56v

Float: 55.5v

Current: 70A

Absorption time: 1 hour


MPPT set to: 56v max

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JohnC avatar image JohnC ♦ david-prentice commented ·
@David Prentice

What I'm getting at is that if it's still accepting substantial Amps, then it's not charged enough to reach Absorb. If the Amps have backed off (maybe to zero), then the BMS is likely responsible.

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3 Answers
Michelle Konzack avatar image
Michelle Konzack answered ·

Your values

56v (absorption) , 55.5v (float)

look very odd. AFAIK the

ABSORBTION must be HIGHER

or the

FLOAT be LOWER.

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david-prentice avatar image
david-prentice answered ·

Thanks for the response, the absorption is higher than the float. Am I missing something?

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Michelle Konzack avatar image
Michelle Konzack answered ·

The difference between ABSORBTION and FLOAT is only 0,5V which can lead to this error.


Please read the Datasheet of your Batterie and correct the values accordenly.

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Related Resources

MultiPlus-II Product page 

MultiPlus-II Manual

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MultiPlus-II 230V Datasheet 

VE.Bus Error codes

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