Please help with my off grid system

[Humble]

Let me start by saying I am new and have never been in forum before. My name is Jason and I am completely off grid. I have read enough of the different topic to realize I know nothing. There are some very smart people in here. I think I have a problem I have been putting my system together slowly in storage till I was able to afford batteries . I installed it all myself and have been using it now about 3 months . I don't know where to start . I live in East Texas have two solar arrays 1 st is renogy 250watts x 10 2500 watts 2nd 8 x 320 watt fabtech 2560 watts all are on a fixed angle of 26.3 OK we'll start over I have to Midnite solar 150 classic charge controller I have been living off grid for several months I have a Magna sine ms 4024pae inverter . I am using crown 430 l16 batteries 12 of them wired 24 volts. My charge controllers ARE set-up equalize 31.2 absorb 28.8 float 26.6 I have been so proud because I found that most days I have hit float but recently I bought the Magna sign state of charge monitor I installed it according to the instructions and with all my gauges and Chargers reading that my batteries are at 26.5 volts my Magna sine SOC Gauge says I am between 43 + 53 percent state of charge. now I am very concerned have I damaged my batteries I have learned by reading these forums that I have been charging my batteries a little hard. I have never seen my battery Bank below 24.3 volts. I set my own hours at 1290 this may be my problem. I have read some of the post and realize that some of you guys are very smart if you can please help. Thank you Jason

[Humble]

I know I have left a few things out and I will be willing to answer any questions to the best of my ability. Although I have never seen 5000 Watts on my charge controller I do consistently see 1500 per controller at about 60 amps per controller so I feel as though I'm getting plenty of power to charge my batteries but I've been wrong before. Thanks Jason

[Sunking]

Howdy and welcome neighbor, former Texan here and an engineer of 40 years. You do not likely have any problem with SOC, No battery monitor system can be effectively used on a working system So cof charge voltages are pretty much useless. Only time you can use voltage as a Ball Park estimate to determine SOC is on a well rested open circuit voltage. That means disconnect every thing for 12 to 24 hours, then measure the voltage. But even then it is only Ball Park.

However you can get very accurate real time readings with a $6 Bulb Type Battery Hydrometer.

Now what is troubling is why you are running 5060 watts on 2 150 Classic Controllers at 24 volts. You should be using just 1 controller at 48 volts into 48 volt 1000 AH battery

[Humble]

Howdy fellow Texan thank you so much for your quick reply. Probably the reason I'm not running my system at 48 volts it's because I don't have any better sense LOL but this is what I have now and don't have a lot of money to change it. I do have
some Hydrometers new I bought but again very new to this and would not be sure how to use them correctly. If my battery Bank has not been below 24.3 volts do you feel that I have drain my batteries too deep? Thanks again Jason

[Humble]

Oh yeah and I forgot with a wife and kids it would be hard to disconnect my system or 12 to 24 hours but I didn't mention that earlier thank you so much for your help.

[Mike90250]

So, what you do is you figure the best time to shut the system down for 3 hours. Let the batteries settle for 3 hours , no loads, no charging and check the SG on all cells
The good news is, you have good voltage, and all batteries are likely still good.
Do one test in the morning, preplan the morning the night before, to use no power, get a reading on the batteries and then run normally, In a day or two, plan on an afternoon test, after the batteries have been in float for an hour or so. Preplan and cut loads - let sit 3 hours, and then read ALL the cells again for SG

Now you have a starting point to begin to fine tune the system.

[Humble]

Ok Mike that is the plan I will post my results asap . Thank you for your help

[Humble]

14833884609501250309772.jpg Ok I am going to try to post a picture of my results. This after it was in float for a couple of hours voltage is still 26.4 on whole bank the batteries are 72 degrees and it's 71 in my house . The batteries sat like 7 house with nothing going in and nothing coming out .

[SunEagle]

I hate to say it but I feel you have an issue due to having 3 strings of 4 x 6v batteries wired in parallel for a number of months. More than likely a few of those batteries are sulfated which may be keeping them from getting back up to 100% SOC.

Did you keep any records of the voltage & cell SG data when they were first put into use?

[Humble]

Man I did not I thought because I had a lot of amps coming in and it was hitting float so often that I was ok and was getting them charged .

[SunEagle]

Man I did not I thought because I had a lot of amps coming in and it was hitting float so often that I was ok and was getting them charged .

Just looking at that list of SG values I saw one battery with a cell at 1255 while it's brothers are at 1265. There were also a few that had 3 different values ranging from 1260 to 1270.

The difference is not much but IMO those lower SG cells may be dragging down the entire system.

[Humble]

I like to say that guy had more money than sense but I don't like it when it applies to me.

[SunEagle]

I like to say that guy had more money than sense but I don't like it when it applies to me.

Well I am not a battery expert so I could be very wrong with my assumptions. But I do know that parallel wired batteries don't stay equal and when one goes the others follow.

[Sunking]

Man I did not I thought because I had a lot of amps coming in and it was hitting float so often that I was ok and was getting them charged .

Humble relax, Everything is just fine The PM sheet tells us everything is OK You are at 95 to 100% SOC and all batteries are all within equalization tolerance.

Read this and what I am going to say will make sense to you.

1. For 100% SOC specific gravity should average 1.270 assuming the High to Low spread is within tolerance.

2. High to Low Specific Gravity be withing .030 points. You are at .015 so excellent condition. When the spread is greater than .030 is time to EQ but not before that point as EQ is a Over charge and does some minor damage in th eform of corrosion. Lessor of the two evils with undercharged being the most evil. So wait until conditions justify an EQ charge.

3, Cell voltage voltage spread from High to Low should be less than 0.04 volts You are at .03 volts with 3-Cells and in excellent shape. Stick with Specific Gravity to determine when to EQ which should fix any unequal voltage issue.

OK with all that said your Specific Gravity is a hair and easily fixed, bump up you Controller Bulk/Absorb voltage a little, and at the end of each day when you go into Float check SG, and adjust voltage accordingly. What you are really looking for is the lowest cell SG to be at least 1.265 and no cell greater than 1.295. FWIW SG is a real time measurement in any state of charging, discharging, or open circuit. It is the only way to determine the true SOC

When it comes time for battery replacement, is the time to correct your initial errors of using to low of a system battery voltage for the amount of panel power, and parallel battery strings. Replace your Inverter and go to 48 volts. You are stuck with 24 volts using 3 parallel strings with 6-volt batteries. Right now you have 24 volts @ 1290 AH. The Equivalent 48 volt battery is 645 AH which might require using 12 4-Volt batteries. Point is go in with a Single String of batteries. Additionally at 5000 watts only require a single Midnight Classic 150 @ 48 volt battery. Maxed out but can be done with a single controller.

So relax, all is well. If you have any questions please ask. You are doing gteat and keep up the Spreadsheet at least monthly as it will extend your battery life and catch problems early before they become a problem. Without it your warranty does not mean squat without proof you did your job.

Happy New Year and God Bless.

[Humble]

So guys I realize I need to check them again when they are at the end of the day but would you guys recommend me taking 4 of these 6 volts off this big bank so that it an 860 ah bank ? In the future I might can afford to switch to 48 but for now I'm kinda stuck wit 24 volts