Hi all,
I hope you can help me sorting out some questions I have regarding my setup, or better, the values shown on my BMV-712.
I built up a solar system using:
- One Q-Cells Q8 module with 355Wp
- One Victron smart MPPT 100/50
- One AGM-battery 12V 202Ah at C20 from offgridtec.com
- One Victron battery monitor BMV-712 including temperature sensor
- One battery protect BP-65 connected to the BMV-712
- One raspberry pi with venus Software connected to the MPPT and the BMV-712
Later on I added a second battery of the same kind and put it in parallel mode (ca. 2 weeks after initial setup), this means I have now 404Ah total capacity.
And now my questions, cause I am wondering if the values or the charge level shown on the BMW-712 is correct.
Now for example the battery monitor shows a state of 77% but got already -138,6Ah, last full charge was 4days 5 hours ago.
I normally have a continous discharge between -10 and -25 watts, sometimes when I need light I had around 150watts maximum consumption.
The temperatures of the batteries are between 0 and 8 degrees Celcius.
For example some days ago still in 1-battery-setup I had at a voltage from 12.2V a state of charge from 75% at a power consumption of 2A (24Watts).
Does this sound like my battery monitor is working correctly?
Its a lot more capacity as I thought I would have, I am getting a little nervous if more than half of the batterys capacity is consumed (202 of my 404Ah).
I don't want to brick my batteries of course :)
Beside the setting of cutting of the less important loads under 60% of SOC, can you recommend a low voltage cut-off-setting? Or is it not important?
Thanks in Advance
Martin