SOK batterie and Victron missmatch in VRM

[RockaChic]

The factory default value of 105 on Charge DC alarm and DCA in SOK, result in CCL and DCL to be 160 in Victron, setting those value to 60 in SOK result in 100 ON Victron CCL and DCL. (Jakipeer batteries show the right value)

1. Is this a bug in the firmware?
2. Why is cell voltage protect set to 3.70 by default, when the maximum for the batterie is 3,65V?
3. Why is charge DC Protect set to 110 by default when the maximum is 100A for the cells?

This is the answers I got from SOK Europe that does not make any sence to me:.

"For battery cell overvoltage protect, yes 3.65V is written in spec.
When the battery reach 3.65v, the battery will be charged by constant current and constant voltage, and the constant voltage up to current is 0.05C.
Our battery pack is charged in the current close to 0.2C, and then voltage will reach 3.7V. The charging will be stop.
This is the way call “Standard charge method”, 0.5C constant current charge to 3.65v for cell, then switch to constant voltage charge until charge current declines to 0.05C.

The cell Maximum charge current (continuous) is 100A.
Which means that it can be charged continuously at 100A from SOC 0 until the voltage reaches the cut-off voltage.
There is no problem with charging this current for a short time, and no need to worry that it will damage the battery.

 

[sunshine_eggo]

1. You're comparing alarm values to protection limits. The BMS only passes limited data to the GX.
2. 3.65V isn't gospel. MANY canned BMS have OVP in the 3.65-3.90V range.
3. No idea

The only issue I see is that you have it set for 110A discharge limit, but the GX shows 100A. The firmware may override your settings with the 100A limit.

It's correctly showing 100A charge limit in the GX per the BMS settings.

In terms of the GX reported values, I'm not seeing any issues.

 

[RockaChic]

1. You're comparing alarm values to protection limits. The BMS only passes limited data to the GX.
2. 3.65V isn't gospel. MANY canned BMS have OVP in the 3.65-3.90V range.
3. No idea

The only issue I see is that you have it set for 110A discharge limit, but the GX shows 100A. The firmware may override your settings with the 100A limit.

It's correctly showing 100A charge limit in the GX per the BMS settings.

In terms of the GX reported values, I'm not seeing any issues.

The value you see in the enclosed picture in GX, is when the alarm values is set to 60 in SOK

 

[sunshine_eggo]

What version GX firmware?

 

[RockaChic]

What version GX firmware?

Latest.

 

[sunshine_eggo]

Sounds like a bug. Alarm values shouldn't influence CCL/DCL at all.

 

[RockaChic]

Same thing with Pack full charge voltage in SOK, 55,2V the value I have set that triggers the pack to SOC to 100% sets CVL to 55,2 in GX

 

[stromy]

The Victron software has lots of additional limits and checks applied to the values from the BMS. I dont know the details, but a lot of the cerbo software is in Python, so you can look into the actual code...
To view the values that get transfered from BMS to Cerbo, ssh into the Cerbo CLI, then use "dbus-spy", navigate to the battery, and look at
Info/MaxChargeCurrent
Info/MaxChargeVoltage
Info/MaxDischargeCurrent
etc.
These should match the settings from the BMS.