WeCo BMS balancing/high voltage issues

DIY
1

This is for Quattro 48/8000 + 2 SmartSolar MPPT VE.Can 250/100 + 250/70
System has 4 packs of WeCo Battery, connected to Cerbo GX via

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Issue was/is - during planned DESS or Scheduled battery charges to 100% WeCo BMS forces Cerbo to rise High Voltage alarms
Here are stages

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Algorythm of BMS seems like looks at cell voltage max/min and reduces charge voltage to the level where balancing is not happening

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Issue - max/min difference is still large, even after ~5 balancing actions

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Could be different battery banks have different settings, but currently no capability to validate this via original BMS wifi access

Solution ( workaround )
By reducing DVCC voltage to 54.5(and after some time to 55.9V) system behaves almost propely, without BMS locks charging, but can’t reach 100% ( stays on 99% of SOC )

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2

Hello, can you show us your settings, especially the settings of the MPPT charger and the charger in the Multiplus?

How long has the system been in operation?

3

I solved this issue by setting DVCC voltage to 55.4-56.4V and system works pretty ok
End up one of the batteries in setup has different parameters than others ( different manufacturing seasons ) which was confusing a system

4

Good to know.

I thought it might be an unfinished balancing of the cell voltages. What is your setting for the absobtion time?

Battery blocks of different ages can possibly cause problems due to different internal resistances during absorption. This could lead to an effect as described in the troubleshooting section 12.

5

No, seems like different packs delivered with different settings. After months this issue exists.

6

Is their firmware different? Or just settings?
It may be best to ask weco for adjustments.