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I installed SONNENSCHEIN A602 SOLAR 8 OPZV 1130 with QUATTRO 48/15000/200-100/100.
According to its manual, battery capacity C10 = 908Ah and C100 = 1096Ah. Accoring to label on the battery, its C120 capacity is 1131Ah.
What number is supposed to be input to VE configure program? C10, 20, 100 or 120?
That depends on your average discharge rate.
If you mostly discharge with C10 you should enter that.
Hi Alexander,
I have also a bigger A602 Sonnenschein 24V battery bank in operation for over a year. For such a big battery bank as yours, I would strongly recommend to use an external battery monitor (eg. BMV712) and not using the internal battery monitor of the Multiplus.
First I tried also only the Multiplus battery monitor but the SoC always drifted completely away especially when the bank was not always fully charged for a few days (autumn, winter). Especially when drawing much power the divergences are getting higher and higher (because there is no peukert correction in the Multi). The VEConfigure battery monitor settings are just rough guesses and therefor (at least for me) not a reliable synchronisation point.
Though, my previous very small battery bank with Sonnenschein SB330 worked quite OK with the Multi battery monitor.
With the BMV712 you can define exact settings for the 100% sync point and the calculations are far more accurate for different discharge currents (see peukert exponent) and of course there is the current measurement via the shunt. I would suggest to invest ~200Euro for the BMV and in the future you will be far more satisfied with your system.
My charger settings are: 29,2V Absorption for max 2h per day and 28,2V Float voltage.
Regards
Rainer
Rainer,
that's definitely an option to try, Thank's for this advice, I hear it for the 2nd time already about BMV and I'm about to place an order.
1. What's your charge efficiency coefficient in VEConfigure? You do not of course enable built in battery monitor and configure BMV directly. So, you must have input it somehow into BMV - I'm not familiar yet how it's done in your case.
2. Do you have a sharp rise in SOC right after 2 hours of absorption are over each day?
3. What charge current do you have within these 2 hours of absorption? Mine is rather low for these large power bank, since I want to get it directly from solar panels - 0-50A in the morning. It's just around 5A per 100Ah of C10, which is definitely too low to carry-out correct charging as prescribed in the battery manual (20A per 100Ah of C10 is optimal as it's written). I guess if I had 100-200A charge current from solar panels then 2 hours of absorption at 2.45V would really be enough to fully charge it from 85% to 100%. And in this case correct charging procedure would be completely and precisely fulfilled. Since I cannot reach 100-200A of charge current yet, I decided to lower absorption current from 2.45V to 2.4V, what allowed me to overcome limitation of 2 hours per day for absorption duration, so that not I can charge with 2.4V for the whole day once a week, what also meets the requirements of the manual, and the switch to flat at 2.3V.
Now, when I decreased charge efficiency coefficient from 95 to 85%, batteries started being charged longer as expected. So, they are not full so far by now (noon), since all same sunny days before they were at 100% by this hour. My understanding is that 85% is closer to correct number of charge efficiency than 95%. I’ll keep observing.
Hi,
to your questions:
to 1): my settings are done in BMV712. I experimented a lot and a charge efficiency of 92% works good for my system. The VEConfig settings are still the default values, but I think they are not used anyway.
to 2) No, usually I have a very smooth rise to 100% SoC. If the batteries are in cyclic operation for a week or so and are never fully charged, it may jump ~3-5% max. with the next 100% charge.
to 3) My max charge current for my 1200Ah bank is also rather low (max 100A with full solar power). But this is not really a problem. The high charge current is required in the bulk phase and not in the absorption phase. If the gel batteries are nearly full, they do not take any charge current anymore. Despite Absorption voltage, the charge current goes down to a few amps. So if you have a lower charge current, you can't use the full capacity of your batteries, but absorption is not the problem.
Here you can see my typical 2h Absorption phase at 29,2V. The current that is taken from the batteries is at start ~50A and goes down to only a few amps after 2 hrs.
And this is how a BMV detects a full charged battery:
The Multi has a complete other method.
Regards
Rainer
Rainer,
why did you decide to use 24V system instead of 48V?
Simply because I had a 24V Multi from my old batteries. I have 2x 24V rows of Sonnenschein batteries, so if I have to replace my Multi sometimes, I will go to 48V too.
Rainer,
can you share with me your setup .rvsc file?
Now when days have become shorter and I had to connect my house to the grid, I detected that in the evening and during the night the batteries are charged with 5A max from the grid within the whole night - a kind of like sustain mode.
I did not have such behavior before. It looks like there's something wrong with setup configuration.
My email: ushakovae@yahoo.com
Hi Alexander,
if you are using the ESS assistant, it seems that the ESS sustain mode is active because the battery voltage is too low - that would match to the 5A current. What is your battery voltage before connecting to grid? See chapter 6.4
https://www.victronenergy.com/live/ess:design-installation-manual?s[]=ess&s[]=manual#sustain_mode
Sustain-voltage level for your batteries: 46V for the first 24 hours, and after that it is raised to 50 V (max charge current is 5A)
I would recommend to read the whole ESS installation manual for detailed information.
Regards
Rainer
My battery voltage is 52.2V, when it started charging from the grid yesterday night with 0.5-1.5A. In ESS sustain voltages are 46/50 V by default.
Rainer, my float is 2.3V and absorbtion is 2.4V.
Repeated absorption time = 24 hours.
Repeated absorption interval = 1 day.
Maximum Absorption time = 24 hours.
What are your settings?
Do I understand you right that you do not perform equalizing charge, since these settings are already the equalizing settings?
No, I do not perform equalizing charge. I simply use the values for cyclic solar operation from the manufacturer manual. I reduced the Absorption voltage a bit.
I do not discharge the batteries more than 30% (70% left).
In the winter season I charge them for 24hrs every 1-2 month or keep them charged at 100% if my panels are covered with snow for a longer time period.
In deep winter I usually allow only a discharge of max. 5% - just to keep the ESS working and have the capacity to store the little amount of solar energy of the day.
Yes, I've seen this chart. And you know what looks suspicious is that in the same manual, where battery manufacturer put the chart in, it's written in one place that float voltage should be 2.3V and in another place - 2.35V. Moreover, there's such discrepancy even on battery sticker: 2.35V-2.45V is recommended on a side sticker and 2.3V for float on top sticker.
I decided to use 2.3V for float and 2.4V for absorption.
Do you hear boiling of electrolyte in your batteries after long charging? Mine ones start boiling after a while.
I think there is not one single valid voltage its more a voltage range (depending on temperature too). I think it depends on the primary usage to serve the expected purpose.
For solar you probably need a bit higher voltages to push the short and fluctuating pv power into the batteries (though not so healthy for the batteries - its a compromise).
If you have only a battery backup system and the float voltage is 24/7 on your batteries, you should select a lower voltage. Thats my opinion.
Yes, I know the very faint bubbling sound. It does it usually after charging when the batteries are at 100% even at @28,2V. I think thats the battery chemistry doing its job. The batteries itself are very cool at +19°C.
Rainer,
I instaled BMV712 with 500A shunt.
What looks suspicious is that I do not know now where 240W of enrgy go to:
Before my quattro consumed 30W, now according to these readings it should consume 240W, but it's not true, because it does not get that warm and fan speed is pretty low.
So I think there's something wrong with setup.
1. Is it the same with your readings?
2. What Peukert exponenta did you input?
3. Did you replace your shung with 1000A one?
What makes me nervous is that at around 12:30 every day battery state of charge is quickly increased from 92 upto 100%. It's not good. I guess it's due to some data, input incorrectly into VE Configure. Can you suppose what it might be?
OPZV batteries are normally around 85% charge efficiency. So it may be that affecting the sudden jump in SOC
I figured out the real cause of such a jump in SOC; according to the batteries manual absorption time should be 2 hours a day at 2.45V and then it should be float mode at 2.35V. So at 11:30 absorbtion was over and float mode started, resulting in significant drop of voltage and charge current and therefore increasing SOC. I changed charging parameters: reduced absroption voltage down to 2.4V, float voltage to 2.3V and increased absorption durationfrom 2 to 12 hours. Let's see.
If OPzV are 85% of charge effeciency, should I input this number into charge effeciency cell in VEConfigure then?
It will help your battery monitor keep better track of your SOC. So yes I would change that.
And thanks for the information on the charge parameters. I am very interested to hear the results of your new configuration from the manual recommendations.
