Battery SOC When topped up by Solar

[houseofancients]

HI,
Are there any issues glaring out regarding the BMS settings?

Thanks

Looks like the default settings, with changed ov protection ( which is charge voltage), like looks fine to me

 

[jassdhali]

I have a bias for setting protection limits to actual limits. 2.5V low and 3.65V high. No damage occurs to cells operating in this range, so there's no reason to force the BMS to narrow this range.

Of course that requires you set the total voltage protection limits to 16X these values.

Set the recovery values to something sensible.

If these are the defaults established by the manufacturer, change at your own hazard.

You program the equipment to operate inside this range.

Cell diff pressure protection of 1V seems pretty extreme given that the cells have a 0.3V primary operating range (3.1-3.4V). I would adjust this to 0.5V

I will look into these values & understand their exact meaning & then move forward.

Only been on this journey since March, so a very steep learning curve.
Thanks

 

[jassdhali]

Looks like the default settings, with changed ov protection ( which is charge voltage), like looks fine to me

Thanks for the feedback.
I will try to understand these more to expand my knowledge.

 

[jassdhali]

I was looking at the custom view on Sunsynk Connect app as below.
Only showing the Battery Voltage, SOC & BMS Voltage.


Is there an explanation for the discrepancy between the BMS voltage & the Battery Voltage?
Is this a natural variation taking battery temp & compression into account.?

Or is that just a daft question. Thanks for your time

 

[GuyG]

Seplos Mason 48V 14.3kWh battery with 16 Grade A V3 LF280K EV

BMS setup advice thanks to @houseofancients

Would anyone with a Seplos Mason (or similar) box be willing to put a micrometer on theirs and let me know what gauge steel is used for the box? I’m thinking about welding up a couple of custom boxes.

 

[sunshine_eggo]

I was looking at the custom view on Sunsynk Connect app as below.
Only showing the Battery Voltage, SOC & BMS Voltage.

View attachment 209786
Is there an explanation for the discrepancy between the BMS voltage & the Battery Voltage?

V-bat is likely reported by the inverter, and it's influenced by current. If charging, V-bat will always be higher than BMS. If discharging, V-bat will be lower than BMS. I suspect the difference to the far right is notably smaller with V-bat more commonly below BMS.

When current is 0A, any difference is measurement error, and devices rarely agree perfectly. If you'd like a 3rd opinion, put a voltmeter on the battery terminals and compare to the other two values.