Old Magnum MS2812 and new Lithiums

[Kevin D Pem]

Hi,
I know this is coming a long time after your note, but I hope you can still see this and are still here.
I have had the oddest thing and extensive testing with input from battleborn, magnum, a genuine rv expert electrical troubleshooter and a ton of headscratching from all......and that is, that with a bank of four battleborn 12v 100aH batteries, all four known to be good individually (we substituted four others, also known to be good and problem is the same, so we know it is not the batteries), and while the batteries register as having a full charge (all settings are absolutely correct in the magnum...I know you have heard this before, but this is the cse)......as soon as the charge is full and the batteries go to rest from a resting voltage of 13.6, the batteries as a bank, drop down to 13.2 in a matter of 10-20 minutes (longer in daytime with solar panels but still "precipitous") and then upon an inverter load, with just a fridge and some 12 volt lights, kind of thing, it is only a matter of another 20 minutes or so before the batteries threaten to go below 13 volts (even at 13.2, the specs show that this is only about a 30% charge but one way or the other, this happens 100% of the time.
there are no other known loads...no ACs runnng...yes, the frdge is a full size but even there, we have replaced it for unconnected reasons and the problem still exists, so it is not that.
we have also tried TWO separate 2812s....both working and tested and STILL no change in the problem.
we can find no ground issues, have triple checked all wiring, have a victron small shunt spliced in so we can also see the voltate on our phone and both the magnum readout inside and the phone show, within a tenth of a volt or so, EXACTLY THE SAME ISSUES.
needless to say we are at wits end.
given your electrician status and that you are an RVer as well, can you opine on this mess? (the panels are connected to a midnite solar controller....all is well, there, too......but even with the batteries showing a full charge and turning the entire solar array off, the precipitous drop is there every time.
tonight, from storm condiitions, the shore power went off and sure enough, from a full charge to 12.9 volts was greased lightning.
can you help?
tnx in advance to you and all and I apologize for th e length of this post but there is a lot going on as you can see.

The question is when the load is removed does the voltage recover?

There is what is known as sitting voltage, and charging voltage. This is that immediate voltage drop,and the true state of charge is when the battery is sitting.

Your charger/charge controller should be set based on the label or literature that came with the battery. This is very important for safety when lithium is your battery of choice. You will read that the charger should be a cvcc voltage source. This means you set your charger to nickel/iron, nicad, or custom, depending on your charger. The setting should be where bulk,and float setting are at the bulk voltage. Further, the equalizer function should be turned off. If you can't turn it off,then set it to the bulk voltage. All this translates to cvcc that your battery manufacturer has told you is Best practice for their product.

Voltage drop is normal! Even the shunt works on this principle. To ensure best possible readings the shunt should be as close to the bank as is possible. And as long as the voltage recovers when no load is applied your good to go! Your voltage meter should be connected directly to the batteries, or the battery buss.

Hope this clears your concerns!

 

[Kevin D Pem]

One more point! Just because the voltage is up does not mean the bank has soaked enough to be fully charged.

Soaking the battery does no harm at the voltage requested by the manufacturer.

A battery monitor is designed to keep track of state of charge. To set one up you must have a fully charged battery at startup! That means you should soak the batteries without using them for the time required for a full charge (this can be calculated). Personally I Just soak for a week to be sure.

Ultimately rock solid is obtained with properly setting things up!!!

 

[nsr1357]

The question is when the load is removed does the voltage recover?

There is what is known as sitting voltage, and charging voltage. This is that immediate voltage drop,and the true state of charge is when the battery is sitting.

Your charger/charge controller should be set based on the label or literature that came with the battery. This is very important for safety when lithium is your battery of choice. You will read that the charger should be a cvcc voltage source. This means you set your charger to nickel/iron, nicad, or custom, depending on your charger. The setting should be where bulk,and float setting are at the bulk voltage. Further, the equalizer function should be turned off. If you can't turn it off,then set it to the bulk voltage. All this translates to cvcc that your battery manufacturer has told you is Best practice for their product.

Voltage drop is normal! Even the shunt works on this principle. To ensure best possible readings the shunt should be as close to the bank as is possible. And as long as the voltage recovers when no load is applied your good to go! Your voltage meter should be connected directly to the batteries, or the battery buss.

Hope this clears your concerns!

Good am, Kevin
thank you kindly!
well, i can only tell you that as per last night....I am in an area where the storm "Debby" has wreaked some havoc on shore power, so this has been an illustrative night.
I do understand the points about "sitting and charging" voltage...and thanks for making that point.

I would not be concerned about it, understand it as I do, but last night, as case in point, when shore power went off, and the fridge and a few 12 volt lights were all that were the load on the batteries, and that meant the amperage draw was about 25-27 amps, it only took minutes for the voltage to drop from 13.2, to not just "13", but it was clear from the flickering, that it was about to drop below "13".

looking at specs on these batteries, even at "13 volts", the batteries are said to be a mere fraction of their full charge capacities, so it sure appears, that the precipitous drop from resting ("silent") at 13.6, to "13.2", without any load (meaning I am still on shore power while all that is happening) continues as a "precipitous drop" when shore power goes off and there is only a modest load (fridge and 12 volt lights).

so it would appear that had I not run the generator, or had shore power not come back on quickly (and at night so the solar panels are not generating any real amount of power...this whole process goes a bit more more slowly during the say when the panels are producing normal amounts of current), that with only a small load, had I not applied additional power...in this case via the generator....those batteries would have quickly dropped below 13 vots and (I assume, but did not want to let it go to that extreme) quickly gotten to a cut off voltage as set via the magnum panel (I think it is set to cut off at 12.5....I am a recent lung cancer patient...nasty surgery.....and have not closely checked all those settings recently, but if memory serves, the cutoff as set at the magnum level before some kind of external charge is called for, is 12.5 volts (in any event, all the settings, having gone thru them MANY times with battleborn, are where they should be at all times).

so net, net, I don't seem to get much out of these batteries, unless the ride down from a "flickering" 13 vots to 12.5, takes a much longer time than would appear).

I hope this all makes sense and I really appreciate your help....due to my health issues, things that may seem like molehills to someone else are "mountains" right now, to me.

many thanks!!

 

[Kevin D Pem]

No pun intended,when it rains it pours!!!

WOW! Looks like there is more than one formidable storm in your life right now! You will be in my thoughts.

Your choice of batteries puts a great teem and product in your corner. The saying that comes to mind is " when you can't, someone will! All you need do is ask!!!" To me I wonder if the batteries are wired for efficient charging,and discharging. This entails equal length cables from source and load. Or proper Flow of energy through All batteries.

Because Debby is massive, I hope your supply of fuel will handle the circumstance, as you can see the sun is hidden in the storm.

My hope is you have garnered enough knowledge to supervise a handyman to help with the actual labor.

Best wishes on your battles!!!

 

[Richpatty]

Hard for me to know what is going on as I am not there, but I still feel like those batteries are not getting to full charge….

And it sounds like you have spoken to all the right folks, but are you sure you have the settings as below? I have a 2812 and 8 battleborns and these settings have worked well.

To set for lithium battery charging in a 12VDC system:

• Press the SETUP button;
• Turn SELECT knob to 03 Charger Setup, Press the Select knob;
• Rotate to 03C Battery Type, press Select knob;
• Rotate to Custom, press Select knob;
  • Absorb volts = 14.4VDC;
  • Float volts = 13.2VDC;
  • EQ volts = 14.4VDC;
  • EQ Done Time = 0.1hrs
• Rotate to 03D Absorb Done Time, press select knob;
• BattleBorn wants this set for 0.5hrs per parallel battery string, if you have 8 12V

batteries then this would be 4hrs.

• Rotate to 03G, press Select knob;
• Rotate to Silent, press Select knob;
• ReBulk volts = 13.2VDC

 

[nsr1357]

Hard for me to know what is going on as I am not there, but I still feel like those batteries are not getting to full charge….

And it sounds like you have spoken to all the right folks, but are you sure you have the settings as below? I have a 2812 and 8 battleborns and these settings have worked well.

To set for lithium battery charging in a 12VDC system:

• Press the SETUP button;
• Turn SELECT knob to 03 Charger Setup, Press the Select knob;
• Rotate to 03C Battery Type, press Select knob;
• Rotate to Custom, press Select knob;
  • Absorb volts = 14.4VDC;
  • Float volts = 13.2VDC;
  • EQ volts = 14.4VDC;
  • EQ Done Time = 0.1hrs
• Rotate to 03D Absorb Done Time, press select knob;
• BattleBorn wants this set for 0.5hrs per parallel battery string, if you have 8 12V

batteries then this would be 4hrs.

• Rotate to 03G, press Select knob;
• Rotate to Silent, press Select knob;
• ReBulk volts = 13.2VDC

thank you so much for your kindness and suggestion. it is, indeed, a hard time but life isn't always "lemonade", either.
as to your questions, and perhaps despite the readings, something is preventing the batteries from a full charge, I am positive about the readings here being correct. indeed, I was walked through it multile times by both battleborn and magnum, and, as well, I am no genius, to be sure, but I do get to know the equipment I am using...self defense if nothing else, and am POSITIVE that the settngs are all correct.
given the symptoms, it would seem to be something heavy, drawing current that is not showing up in any readings.....a malfunctioning arctic package for example, but while I don't think that is the case, it looks as nothing will replace taking the faceplate off the breaker board and putting a VOM on every one of them with shore power off to see if anything crazy is going on.

that said, thank you SO MUCH for the handholding.

robert

 

[nsr1357]

thank you so much for your kindness and suggestion. it is, indeed, a hard time but life isn't always "lemonade", either.
as to your questions, and perhaps despite the readings, something is preventing the batteries from a full charge, I am positive about the readings here being correct. indeed, I was walked through it multile times by both battleborn and magnum, and, as well, I am no genius, to be sure, but I do get to know the equipment I am using...self defense if nothing else, and am POSITIVE that the settngs are all correct.
given the symptoms, it would seem to be something heavy, drawing current that is not showing up in any readings.....a malfunctioning arctic package for example, but while I don't think that is the case, it looks as nothing will replace taking the faceplate off the breaker board and putting a VOM on every one of them with shore power off to see if anything crazy is going on.

that said, thank you SO MUCH for the handholding.

robert

ps the string is 4 batteries and not eight....they replaced four lifeline AGMs...albeit now, with appropriately different settings.

 

[nsr1357]

No pun intended,when it rains it pours!!!

WOW! Looks like there is more than one formidable storm in your life right now! You will be in my thoughts.

Your choice of batteries puts a great teem and product in your corner. The saying that comes to mind is " when you can't, someone will! All you need do is ask!!!" To me I wonder if the batteries are wired for efficient charging,and discharging. This entails equal length cables from source and load. Or proper Flow of energy through All batteries.

Because Debby is massive, I hope your supply of fuel will handle the circumstance, as you can see the sun is hidden in the storm.

My hope is you have garnered enough knowledge to supervise a handyman to help with the actual labor.

Best wishes on your battles!!!

thank you so much for your kindness. i don't have a handyman to do this, but I can arrange for someone who knows this unit extremely well, to walk me through this process of doing what I guess has to be done, which is to put a VOM on every breaker...while we are on the phone.

in better days, I would have done this already....but it is what it is.
anyway, thank you again for your commiseration and goodness.
robert
PS i have never seen so much rain as I have the last 24 hours with the bands from debby, even as I am not in the main path. it is still raining and it would not surprise me to learn that we have had 5-8" in less than 24 hours.

 

[nsr1357]

pps years ago, i had the factory plumb in four extra 20 pound tanks (in addition to the two 40 pounders that came with the RV) so I actually have 160 pounds of propane on aboard if needed. that said, the onan generator is 5500 watts, so the good news is that it can do a lot. the bad news is, obviously, that it drinks propane like and alcoholic drinks scotch.
in a serious pinch, I can probably run the generator full out, including some AC use for about 5-6 days without running out of fuel.

that said, I recently had installed a ductless ac installed in this box and soon i will be running it and some other items...mostly communications radios.......off of a second set of panels, new <victron> equipment and separate battleborn battery bank, and none of that is plumbed into the trailer ecosystem....so that will handle the ductless ac and a lot of other things for a long time without relying on the main system which has to worry about such as the fridge, arctic package when needed, etc......although this second system will have to take recharging power solely from the roof panels...unless i want to go a lot further to hook it up to shore power, too...but the whole idea is not to need shore power for extended periods.

 

[Richpatty]

If there was a draw taking the batteries down, it would show up on the shunt reading…it would show how many amps have been draw since last charge. I apologize for what might be a dumb question, but are ALL grounds running through the shunt?