Shunt is reporting 100% but still only 13.47v. The controller is jumping between Absorption and Bulk so I assume there's still a bit to go.
What does the Power 120watts mean?
Victron Solar Mppt 100/30 - Detail monitoring (7 Viewers)
- Thread starter acenip
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What does the Power 120watts mean?
- Apr 9, 2022
- 541
- 543
- Funster No
- 87,949
- MH
- Cathargo
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- Newbie
Power 120watts: The voltage reported from the battery is 13.47v and you have a current flowing of 8.94amps - This will produce 13.47volts X 8.94amps = 120.42Watts. A watt is a measure of power or how much work it can do. Volts and amps on their own don't tell you much, but Watts do so a 1000w Kettle, could be 230v drawing 4.3amps, or 12v drawing 83amps, both will boil the water at the same speed.......
Has the battery got up to 14.2v yet? Might be worth turning any loads off to keep the charge high as possible....
The shunt is obviously out of sync with the battery, but to get it back in line the voltage/tail current etc must get up to the values in your shunts settings when it will reset.
You can also reset it manually, but the only time you can accurately know what the correct SOC is, is when it is full (and cell balancing is complete).
Lithiums are difficult to estimate, because the voltage will not change much as they charge - then when they are nearly there the voltage will rise very quickly (few mins) to 14.2.
Not sure why the solar charger is dropping in and out of absorption though, but at 13.47v it is close, so hopefuly the voltage will jump soon.....
PS. might help it along a bit if you put the shunts tail current up to 2%ish - but the battery must get up to 14.2 as well.
Has the battery got up to 14.2v yet? Might be worth turning any loads off to keep the charge high as possible....
The shunt is obviously out of sync with the battery, but to get it back in line the voltage/tail current etc must get up to the values in your shunts settings when it will reset.
You can also reset it manually, but the only time you can accurately know what the correct SOC is, is when it is full (and cell balancing is complete).
Lithiums are difficult to estimate, because the voltage will not change much as they charge - then when they are nearly there the voltage will rise very quickly (few mins) to 14.2.
Not sure why the solar charger is dropping in and out of absorption though, but at 13.47v it is close, so hopefuly the voltage will jump soon.....
PS. might help it along a bit if you put the shunts tail current up to 2%ish - but the battery must get up to 14.2 as well.
Last edited:
Finally some really bright sunshine so hopefully I'm coming to the end of thie journey setting up my solar/lithium.
From what I see this morning on both apps charging seems to have stopped as I've reached full capacity.
From what I remember I now need to manually reset my shunt to have it recalibrate the battery. Is this correct?
From what I see this morning on both apps charging seems to have stopped as I've reached full capacity.
From what I remember I now need to manually reset my shunt to have it recalibrate the battery. Is this correct?
- Apr 9, 2022
- 541
- 543
- Funster No
- 87,949
- MH
- Cathargo
- Exp
- Newbie
Yes its doing what it should!
Given the solar is still in the absorption phase I would let it finish or at least give it an hour or so for cell balance, but the shunt has already reset to 100%, so you should be fine to leave it now.
The shunt doesn't reset the battery as such, it simply measures and displays the net result of incoming and outgoing currents (charging and loads), and for simplicity it nets those off against the battery capacity you enter in the battery settings screen.
A shunt is very good when the battery is in use and cycling regularly, but a small error can build when currents are very small, and or very large. Its difficult to get these errors dialled out completely using the various settings, and over time the error will compound unless the battery gets full (as it now has) and resets back to 100%
Given the solar is still in the absorption phase I would let it finish or at least give it an hour or so for cell balance, but the shunt has already reset to 100%, so you should be fine to leave it now.
The shunt doesn't reset the battery as such, it simply measures and displays the net result of incoming and outgoing currents (charging and loads), and for simplicity it nets those off against the battery capacity you enter in the battery settings screen.
A shunt is very good when the battery is in use and cycling regularly, but a small error can build when currents are very small, and or very large. Its difficult to get these errors dialled out completely using the various settings, and over time the error will compound unless the battery gets full (as it now has) and resets back to 100%
Great news, thanks to everyone who contributed. 
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