my "unsolvable problem"

[olmz]

This is true given a sufficiently long absorption time or sufficiently slow (low C rate) charge cycle.

With this in mind and moving to other areas, i am wondering about what the actual charge profile is set to? I am not familiar with the Magnum 2812 (nor any Magnum inverter charger).



It would be very interesting to see the individual battery voltages with no loads or other connections to verify the. I understand it would be perhaps too much effort to confirm this curiosity. Is it possible to disconnect the battery (lower right switch in latest pic) and measure the voltage after an hour when you see the reading "below 13 volts"?

And...
A quick search reveals a thread that talks about 2 programable profiles (silent and float).

Silent charge or float?

I have a Magnum MS1212 2000w / 100A 12v inverter-charger in my motorhome. By batteries are a couple of drop-in 460Ah packs for a total capacity of 920Ah I am trying to decide which charge profile to use with I am plugged into a full hookup site. I have two programable profiles that should...

diysolarforum.com

Can you confirm your charge profile and settings?

Sorry i have so many questions. Just trying to follow clues and what i recall about dealing with other/similar issues.

i am soon to measure some indvidual voltages as requested by another poster, but prior to using any of these batteries, they were all charged using a victron ip65 and all of them fully charged and held their voltages over time periods much longer than the drops I am experiencing now.

i can confirm without question, both the validity of the settings and having tried a number of different ones....as well as a lithium ion preset in the magnum unit....thousands of which, I might add, are in successful service today and for many years.

no problem on questions..sooner or later something is going to occur to someone that helps find this....but I can say without hesitation, that no settings or equipment directly involved....inverter/charger, etc.....is presently implicated in this.

it is too odd..the whole thing but we are being thorough in testing everything. I have a full set of replacement wires, too, and if all else fails, will replace every wire in use to see if somehow, despite the maker of the wires and that they all look fine, there may be something going on there.

I am hoping to have the busbars installed within a few days....don't expect it to change anything but it will make moving around with the array, easier, anyway....and they are known bars....from victron, with plenty of amperage capacity.

i will certainly post all results here.

 

[MisterSandals]

I have a full set of replacement wires, too, and if all else fails, will replace every wire in use to see if somehow, despite the maker of the wires and that they all look fine, there may be something going on there

If the wires or connections are an issue you would certainly detect warmth with your fingers. Issues like you are seeing would be too hot to touch.

but I can say without hesitation, that no settings or equipment directly involved....inverter/charger, etc.....is presently implicated in this.

There might be clues or things to rule out if you share your charge settings.

they were all charged using a victron ip65 and all of them fully charged and held their voltages over time periods much longer than the drops I am experiencing now.

You have top tier equipment but thats not reason to rule out that they have not developed problems.

 

[olmz]

If the wires or connections are an issue you would certainly detect warmth with your fingers. Issues like you are seeing would be too hot to touch.


There might be clues or things to rule out if you share your charge settings.


You have top tier equipment but thats not reason to rule out that they have not developed problems.

no problem.

14.4 volts for absorb (also tested at 14.6 once, per the maker), 13.6 for float, and 13.2 for bulk...

when this odd cycle begins, bulk flashes by for a moment but then goes right into absorb....which while set at 14.4, sometimes shows up as 14.3....again, BB knows all that. absorb is set for two hours, but sometimes it exceeds that in fact....although I have done so many cycles that I don't recall exactly when...I am just aware that it has happened.

of course, if set to "silent", then one does not see a float, but if the end is set to "float" then of course, one does...but it still does not stop the drop.

i have also tried, as mentioned, the lion preset and while it changes the numbers slightly, it never makes the problem go away.

these batteries do not need equalization, but the settings require something so it is set to, I think, a few minutes or something like that....with the goal being not to equalize them at all.

 

[WindWizard]

The thing that is really puzzling is that once the pack gets down to 13.1 volts then it seems to hold. If it was just a current drain then I don't think that would be the case. I am looking forward to you getting the current probe so you can provide us with more information.

 

[MisterSandals]

13.6 for float, and 13.2 for bulk...

Do you have these written backwards?

It would explain your odd charge cycle.

 

[olmz]

Do you have these written backwards?

It would explain your odd charge cycle.

i meant to say "rebulk" at 13.2. sorry.

float is definitely at 13.6 in custom settings for the magnum, there is no separate bulk voltage setting in this instance, but the battery maker shows that 14.4 is for both bulk and absorb, so it amounts to two settings and then a third for equalization, although in this case it is setting it to an absorb setting but one tenth of an hour....meaning that to the battery is not an equalization setting as it does not need equalization as some AGMs do.

 

[olmz]

The thing that is really puzzling is that once the pack gets down to 13.1 volts then it seems to hold. If it was just a current drain then I don't think that would be the case. I am looking forward to you getting the current probe so you can provide us with more information.

I agree, which is why i mentioned that very thing. if I let them site long enough, the voltage will eventually (in this problem way) drop below three......and eventually to a level where the inverter charger turns itself off......12.x.

why, that said, it stops at 13.2 or so, I agree is probably a real tell, but I just don't know what it is.

now, with charger toggled off at "float", and the batteries at 13.6 (if using "silent", one cannot actually toggle the charger off, but if set for final state at "float", one can), it then dropped down as it has been doing....and stopped where it has been stopping.....but now that it sat there in the low 13s for a couple of days, it has gone down another 10th to 13 exactly.

if there were some extraordinary drain, I would have thought that it would blow right though the low 13s and get to a point where the inverter shuts down (which this magnum will do when the voltage goes low enough)...but that has never happened.

 

[Ampster]

there is no separate bulk voltage setting in this instance, but the battery maker shows that 14.4 is for both bulk and absorb,

That is often the case because bulk is a constant current setting in which voltage increases as the battery gets full. The setting is actually the point where the charger transitions from constant current to constant voltage and that is why it is only necessary to have one number as the setting.
Rebulk is a different thing. It is the setting that turns on Bulk when the battery gets that low.

 

[HighTechLab]

Settings posted @olmz looks fine. I don't think you should change anything from where you started.

I'm not sure there is really an issue. Use a shunt and watch % SOC instead of battery voltages. LiFePO4 voltages are very hard to judge. For example, 12.8v could be 90% or 10% depending on what's going on with the system.

I never look at battery voltages in my RV, I use a Victron Smartshunt and look at the SOC% on that. Best $130 ever spent. My batteries are dead at 0% and stop charging at 100%. This means they are full capacity and life is good.

The nominal voltage of LiFePO4 is 12.8v. If what you were reporting was that they were dropping to 12.2 vs 13.2, I'd raise an eyebrow. At 13.2, your batteries are still pretty much full...is this unsolvable problem actually a real problem?

 

[olmz]

That is often the case because bulk is a constant current setting in which voltage increases as the battery gets full. The setting is actually the point where the charger transitions from constant current to constant voltage and that is why it is only necessary to have one number as the setting.
Rebulk is a different thing. It is the setting that turns on Bulk when the battery gets that low.

noted with thanks.

 

[olmz]

Settings posted @olmz looks fine. I don't think you should change anything from where you started.

I'm not sure there is really an issue. Use a shunt and watch % SOC instead of battery voltages. LiFePO4 voltages are very hard to judge. For example, 12.8v could be 90% or 10% depending on what's going on with the system.

I never look at battery voltages in my RV, I use a Victron Smartshunt and look at the SOC% on that. Best $130 ever spent. My batteries are dead at 0% and stop charging at 100%. This means they are full capacity and life is good.

The nominal voltage of LiFePO4 is 12.8v. If what you were reporting was that they were dropping to 12.2 vs 13.2, I'd raise an eyebrow. At 13.2, your batteries are still pretty much full...is this unsolvable problem actually a real problem?

thank you. if I may, and respectfully, it seems to be a significant problem to many, including battlenorn when I first approched them about it...they are a good company, btw.

indeed, as you will see from this link, they say that 12.8volts is not even 20% reserve:

Battleborn Voltage Chart: At What Voltage Is a Battery Dead?

They are classified as 12-volts but you need to be higher than 12 volts to have a fully charged battery. A battery is considered dead once it hits 11.9 v...

thecampingadvisor.com

so that may be enough to keep the inverter running...andf I am becoming aware that it is correct that this may not always be even a totally exact science...............more complicated, including solar than just get it and hook it up ....................it needs to see 12.x volts, but unless I am missing something significant, it makes a substantial difference.

so while I am not knowledgable enough to be aware of every nuance, this seems to be well beyond "nuance" into "something is not right'.

but I welcome any other comments so please have at it...as i would find it awful if indeed, it turns out that voltage readings even from the charger, mean nothing....in favor of SOC readings on a shunt (I am not doubting you, but I am in a situation where there are very heavy demands on my electrical system..emergency radio equipment, for one example.............. and in the circumstances that I am concerned about with this whole issue, should I find myself with real diminished capacity (not talking about my mental state from all these new things I have to learn ), that would be a very nasty matter...so I am going with all those voltage readings, especially as they come from the maker.

 

[WindWizard]

Settings posted @olmz looks fine. I don't think you should change anything from where you started.

I'm not sure there is really an issue. Use a shunt and watch % SOC instead of battery voltages. LiFePO4 voltages are very hard to judge. For example, 12.8v could be 90% or 10% depending on what's going on with the system.

I never look at battery voltages in my RV, I use a Victron Smartshunt and look at the SOC% on that. Best $130 ever spent. My batteries are dead at 0% and stop charging at 100%. This means they are full capacity and life is good.

The nominal voltage of LiFePO4 is 12.8v. If what you were reporting was that they were dropping to 12.2 vs 13.2, I'd raise an eyebrow. At 13.2, your batteries are still pretty much full...is this unsolvable problem actually a real problem?

You do have a very good point. The only thing that makes me wonder is the OP mentioned that his system has been functioning okay for seven years and now things are different. The other thing that I noticed on my system is that right now I have a smart shunt in my system and the state of charge is about 50% according to Victron's math and my cell voltage is 52.19 volts or 13.05 volts. (12 volt equivalent voltage).

But then again you may be entirely correct.

 

[olmz]

You do have a very good point. The only thing that makes me wonder is the OP mentioned that his system has been functioning okay for seven years and now things are different. The other thing that I noticed on my system is that right now I have a smart shunt in my system and the state of charge is about 50% according to Victron's math and my cell voltage is 52.19 volts or 13.05 volts. (12 volt equivalent voltage).

But then again you may be entirely correct.

The cheapo clamp on meter that I keep in my RV is no longer available, so I can't recommend it. Here is one that came to the top of the list when I searched on Amazon:

https://www.amazon.com/Multimeter-Auto-ranging-Temperature-Capacitance-Plusivo/dp/B08MTY51R4

It doesn't have to be this one. The key is that it MUST be capable of "DC current".

Hi,

I've been held up with an unscheduled medical issue......just wanted you to know that I have certainly not forgotten the measurements you asked for. also, that device you suggested is supposed to arrive today, as well.
Kindly bear with me...this remains at the top of my list for things I have any choice about....just been waylaid by doctors.
thank you.

 

[olmz]

I am going to presume (for the moment) that all the batteries are reaching the same voltage. Measuring one of them (for now) should suffice. What I am aiming to do is to see if the voltage at the inverter matches the voltage at the battery. If not, then there is some connection issue someplace causing voltage drop. If it is the same, then we're likely ok on the connections and need to find why the batteries are appearing to slump so fast.

Hi,

Just wanted to let you know that I have been held up by unexpected medical needs. This remains at the top of my list and I hope you will kindly stand by for just another day or so...and I will be forwarding the measurments we discussed. thank you so much.

 

[olmz]

Hi,

Just wanted to let you know that I have been held up by unexpected medical needs. This remains at the top of my list and I hope you will kindly stand by for just another day or so...and I will be forwarding the measurments we discussed. thank you so much.

I am going to presume (for the moment) that all the batteries are reaching the same voltage. Measuring one of them (for now) should suffice. What I am aiming to do is to see if the voltage at the inverter matches the voltage at the battery. If not, then there is some connection issue someplace causing voltage drop. If it is the same, then we're likely ok on the connections and need to find why the batteries are appearing to slump so fast.

Good morning,

Just wanted you to know that I have begun to take the measurements you suggested. the charger/batteries are in the middle of this never ending charge cycle, showing "absorb" on the magnum panel, with voltage at 14.3 volts, "flickering" to 14.4 volts (and at 10 amps at the moment, but this is probably late in the charge cycle and I am just first able to get to this now, after a few less than accomodating days).

i have actually measured at all four batteries, and each is showing 14.4 volts, with two flicking momentarily at 14.5 volts.

I have designated, as you suggested, one battery for this little project, so going forward I will report on just one....but so far all looks to match...meaning the magnum panel readout and the batteries (all are obviously still hooked up).

kindly stand by...as soon as the absorb finishes and we get to "silent", I will go out and measure again.

thank you!

 

[olmz]

Good morning,

Just wanted you to know that I have begun to take the measurements you suggested. the charger/batteries are in the middle of this never ending charge cycle, showing "absorb" on the magnum panel, with voltage at 14.3 volts, "flickering" to 14.4 volts (and at 10 amps at the moment, but this is probably late in the charge cycle and I am just first able to get to this now, after a few less than accomodating days).

i have actually measured at all four batteries, and each is showing 14.4 volts, with two flicking momentarily at 14.5 volts.

I have designated, as you suggested, one battery for this little project, so going forward I will report on just one....but so far all looks to match...meaning the magnum panel readout and the batteries (all are obviously still hooked up).

kindly stand by...as soon as the absorb finishes and we get to "silent", I will go out and measure again.

thank you!

the panel voltage has already begun to drop in silent mode.....just a few minutes after going *into* silent mode, and with the magnum panel showing 13.9 volts, two batteries, including the one we are paying close attention to, measured 13.8 volts. here we are now...jut a few minutes later, showing 13.5 volts on the magnum panel and the battery (actually two of them, including our "official" test battery) measure 13.6 volts at terminals.

so provided that we have a consistent tenth of a volt difference between magnum panel and battery(s), unless you think that is significant, they are the same.

thanks again.

 

[jberger]

Please post up the settings from your magnum remote so we can see the charging settings and inverter settings.

You do not have a magnum BMK shunt kit, correct?

 

[olmz]

the panel voltage has already begun to drop in silent mode.....just a few minutes after going *into* silent mode, and with the magnum panel showing 13.9 volts, two batteries, including the one we are paying close attention to, measured 14.8 volts. here we are now...jut a few minutes later, showing 13.5 volts on the magnum panel and the battery (actually two of them, including our "official" test battery) measure 13.6 volts at terminals.

so provided that we have a consistent tenth of a volt difference between magnum panel and battery(s), unless you think that is significant, they are the same.

thanks again.

so one thing. my previous observation of the panel voltage "settling in" at 13.6 was not actually correct....very sorry...it is clear that this time, anyway, and perhaps this has been the case all along, the voltage at silent, has begun, at least some times, higher than 13.6....this is all happening so fast that perhaps the "13.9" volt panel measurement actually started at, say, 14.0 or 14.1......but nevertheless, the precipitous drop starts immediately and is already not far from the 13.2 or 13.1 at which it rests every time (regardless, then, of the starting voltate, so to say).

 

[olmz]

Please post up the settings from your magnum remote so we can see the charging settings and inverter settings.

You do not have a magnum BMK shunt kit, correct?

sure. they remain at 14.4 for "absorb", 13.6 for "float" and 13.2 for "REbulk".
at this "custom" setting group, there is no separate setting for "bulk", but BB says that the bulk and absorb settings should be the same at 14.4 (and as high, I think, as 14.6).

at BB's direction, I have, indeed, tried 14.6 volt setting for "absorb", but it made no difference in the matter.

thank you.
PS later today or tomorrow, I am going to try CC/CV settings, the one thing not tried yet with all this back and forth.

 

[olmz]

sure. they remain at 14.4 for "absorb", 13.6 for "float" and 13.2 for "REbulk".
at this "custom" setting group, there is no separate setting for "bulk", but BB says that the bulk and absorb settings should be the same at 14.4 (and as high, I think, as 14.6).

at BB's direction, I have, indeed, tried 14.6 volt setting for "absorb", but it made no difference in the matter.

thank you.
PS later today or tomorrow, I am going to try CC/CV settings, the one thing not tried yet with all this back and forth.

PS the problem remains whether I use these custom settings as BB directed, or the magnum preset for Lion batteries