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Smart Shunt Charged Voltage

I installed my Smart Shunt on my 230 AH FLA battery bank and set the charged voltage to the recommended 13.2V. After loading for 4 hours at 10 amps I was at 83% when I disconnected the load and connected the charger (IP65 12/15). The SOC display reached 100% while the charger was still in absorption. Is this acceptable or would my SOC display be more accurate if I raised the charged voltage to a point where SOC would not reach 100% till the charge went to float?

smart shunt
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2 Answers
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JohnC answered ·

Hi @bigb

With fla's it's best to keep Charged V below the Float setting, just enough to avoid the temp-compensated Float target.

What you may be seeing though is the Tail amps (as %) being set too high. I think the default is 4%, way too high for me (I use 0.6 or 0.7%).

With a 13.2V setting it may also be possible to reach sync 'on the way up', rather than while actually tailing. If that ever happens you could increase the Detection Time a little, say 5 min.

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bigb answered ·

Thank You JohnC, I will study up on the tail current so I have a better understanding of just what purpose it serves, and perhaps increase the detection time. I noticed the Victron Smart chargers always go to float for 4 hours before going to storage, while bulk and absorption times vary according to initial SOC. Float time never varies and I wonder if 4 hours of float is acceptable in all conditions.

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