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chris-5 asked

SmartSolar MPPT not charging FreedomWon battery past 90%

Hi there


I have a site with the following setup:

1. 5kW Multiplus II

2. 1 x SmartSolar MPPT 250/60 with 8 x 375W PV panels

3. 1 x SmartSolar MPPT 250/60 with 8 x 380W PV panels

4. 2 x FreedomWon 10/8 LiFe batteries

5. Color Control GX


The system will start off in the morning charging at 100% (using all the available solar power). Then when the battery reaches 90% the one SmartSolar MPPT will almost switch off. The one MPPT will charge at +-1800W which is the size of the load and the other MPPT will charge at +-10W. This means the battery does not charge to 100%.


If I change the settings so that the system exports power, both MPPTs provide all the available power which was +-4400W at that stage.


Any ideas why this would happen? I replaced one of the MPPTs recently and did Firmware upgrades on the whole system and now I noticed this.


Kind regards

Chris

battery chargingMPPT SmartSolarsmart solar charging behaviourfreedom won
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Mike Dorsett avatar image Mike Dorsett commented ·
If you are changing settings to "export power" then you must have a Venus GX device, that is not listed in the equipment above. The voltage settings programmed here will set the max charge voltage. SOC is a concept rather than a physical parameter.
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jason-lane answered ·

Check the battery voltages being reported by the MPPTs and compare to the voltage being reported by the battery itself (the BMS). If the MPPTs are reading a higher voltage than the BMS, they may think the battery is already full. This was happening to me, and I found that enabling Shared Voltage Sense (SVS) in the DVCC section fixed the issue. The MPPTs now reference the BMS battery voltage.

You can read more about using DVCC here:

https://www.victronenergy.com/media/pg/CCGX/en/dvcc---distributed-voltage-and-current-control.html

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Additional resources still need to be added for this topic

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