Batteries - Parasitic 12V Draw or Something Else

[bpcannan]

Here's the scoop and I hope someone might have advice, insight, or direction for me.

My 3 100AH LiFePo4 Battleborn batteries do not seem to be holding a charge and I cannot figure out why.

My setup in a 2010 Journey Express 34Y is 3 - 100AH Battleborn batteries connected to a Victron 3000 Watt 2 X 120V Inverter/Converter with a BMV712 monitor and a 225Amp Li Battery Isolation manager.

The situation over the last 48 hours...

drove 6 hours today (Wedneday) after charging batteries while driving 7 hours tuesday and then leaving them on shore power charge overnight.

Forgot to flip the charging swich while driving today but BMV712 showed 100% SOC after the driving 6 hours today. Ran the fridge on propane and had 2 garmins going

got set up at 3 pm cdt on 50 amp shorepower running only the fantastic fan, the fridge and a floor fan from the passenger seat 120V outlet but did not think flip switch to charge batteries on shore power

went out at 5 came back 7

coach battery light was off, nothing dependent on 12 volt was working but the 120 line by passenger side was working the small portable fan and TV in bedroom powered onwhen tested
no fridge, no stove, no overhead fan, no lights no coach battery light switch on by the entry door - chassis battery light on but not coach

shore power checked ok
reset 120 fuses
reset 12 volt fuses
entire control panel on inside coach wall was blank - everything except the section show L1 and L2 had power and no error codes

opened battery compartment and checked voltage on each battery
0.0 0.32, 0.0 volts but did not disconnect the cables while doing this so maybe that info is not helpful

It was an OMG moment as we are at the start of a 6 week outing.

So as a last resort i flipped the switch on the wall panel that controls charging and inverter use to battery charge and poof everything is working

I haven’t a clue - other than a circuit got completed

The wall was in bulk mode for about 30 seconds then flipped to absorption mode and the voltage on the BMV unit reads 14.37 with 6 bars showing the batteries are fully charged

my victron BMV phone app shows infinity for length of use time and 100% SOC with -0.50A and Consumed Ah at -1AH with remaining battery life at 10d 0h

btw chassis battery voltage reads 13.8

Soooooo
Parasitic draw?
Faulty battery Isolation manager
Bad Batteries
Too hot in my battery compartment messing up the 3000W inverter

Any insight or advice is welcomed

Thank you.
Brian

[powercat_ras]

The things you can not turn off that you need together draw about 12 amp-hours of 12 volts each day. Propane detector, refrigerator control board, thermostat.

In my Winnebago there were other things that drew about another 12 amp-hours per day that were not critical and I shut them all off except when using them...

12 volt feed to the roof antenna signal amplifier - turn off when not watching TV.

12 volt powered infrared remote control signal repeater that uses power all the time, I wired a on-off switch in series with mine and turn off when not needed.

12 volt powered to 120 volt AC inverter. When on even if you have everything AC powered you can turned off it will still use 30 amp-hours per day when it is on. There also may be some parasitic AC draws associated with entertainment system stuff such as HDMI and/or Component Video splitter/amplifiers, sub-woofers, sounders, etc. You can look at electrical information on your specific RVs entertainment system on winnebago's web site.

[Morich]

Some small points to consider if maybe you are missing them? One is the readings on the batteries and when/how they can confuse us. A reading of totally zero? That seems really hard to do, but I also can't argue with what or how you checked it. Not close enough to watch!
But then the sudden jump to full voltage when turning on any form of charging? That is not a real indication of the real state of charge but what we call " surface charge". What I would guess you were seeing was not the battery fully charged but the voltage from the charging showing at the point checked.
Something like filling a barrel with water and looking right at the stream going in while the barrel is only part full? It can look like there is a lot of water but we are only seeing what is going to eventually fill the barrel!

I can't really point to what happened but there are small points that might lead to this looking so bad?

consider how you took the voltages as "maybe" a clue?
It is easy to get bad habits on reading the voltage and we can miss small points.
When reading, if we put the probe on the clamp where charging is coming to the battery, we can see 13+ but if we have a corroded connection on that battery, the post itself where that power goes into the battery can be way down! When reading battery voltages, it is good practi=ce to read the clamp and then also the post itself to make sure they are actually clean and well connected!

That can lead to wht I think you mean. Things are all dead when charging is off but all work fine when charging is on.
Thinking of the battery as supposed to STORE energy, we may be actualy using the power from the charger but nothing in the battery that we can get out due to dirt in the way?
Maybe some checking of the setting on the charge system to make sure it is actually set high enough to top off the batteries as I see a number of reports of this a as a problem?

Lots of thoughts on what "might" have happened but little to say for sure!

But a battery drain that acts that quick to go from good battery levels to totally flat is pretty likely to blow some fuses, trip breakers or do some arcing! The small drains of the detectors, etc are so low that it should take days to get the batteries down flat if they were actually getting fully charged!

I feel like something is tricking you on something simple?

[bpcannan]

thank you
i’ll do some thinking and maybe audit/write down possible draws
brian

[bpcannan]

it has to be something simple tricking on me

the victron bmv712 monitor is in stalled in the wall in such a way that i can’t get the puk code on the back of it to start the re-pair process. i was reading the default setting is for lead acid batteries so without re-pairing i am likely getting false state of charge readings which can hamper my thinking about my problem too.

thanks for replying
brian

[creativepart]

Isn't the PUK code on the shunt too? It is on the SmartShunt, but obviously a different model, so maybe not.

Looks like you pop the front cover off and unscrew 4-screws and then rotate the monitor to unscrew it to remove it from the wall. But you need access to the space behind to keep the screw cap from falling into the void behind.

https://www.victronenergy.com/upload...de-BMV-712.pdf

[Morich]

I'm way out of my field on the newer battery types so correct me if wrong as I've mostly read about hem rather than KNOWING!
But is it not true that they should show a higher voltage than lead acid when fully charged?
Would that make it possible to just let you check them for voltage after they should be fully charged but with the charge voltage turned off? After a couple hours with no charge and with as much drain turned off as practical?
Got a meter on hand to do a check directly at the batteries to avoid any confusion with possible monitor questions?

I always need to remind myself that problems are often dirt and corrosion, more than actual equipment failures.
So there may be more than one path to get charge into the battery and another to get it out?
I'm coming back around to the basic idea that thing work as long as charger is providing the power but stop when the charge stops. That tends to make me think the charge is not actually getting to the batteries or the path to get it back out to use it may be the problem?

I'm prettty far out on that limb, though!! I'm so much involved with drawings and figuring out what they tell me that I get nervous when I can't look at paper!

[bpcannan]

Right on that.got the cap and unscrewed the cover but finding the right tool or way to hold the unit while unscrewing is an issue and I didn’t watch on the install and have zero access behind the wall. Still trying to figure this one out.

Thanks

[bigb]

Originally Posted by powercat_ras

The things you can not turn off that you need together draw about 12 amp-hours of 12 volts each day. Propane detector, refrigerator control board, thermostat.

In my Winnebago there were other things that drew about another 12 amp-hours per day that were not critical and I shut them all off except when using them...

12 volt feed to the roof antenna signal amplifier - turn off when not watching TV.

12 volt powered infrared remote control signal repeater that uses power all the time, I wired a on-off switch in series with mine and turn off when not needed.

12 volt powered to 120 volt AC inverter. When on even if you have everything AC powered you can turned off it will still use 30 amp-hours per day when it is on. There also may be some parasitic AC draws associated with entertainment system stuff such as HDMI and/or Component Video splitter/amplifiers, sub-woofers, sounders, etc. You can look at electrical information on your specific RVs entertainment system on winnebago's web site.

Don't forget about the electric propane solenoid valve if equipped.

[Marine359]

If you want to turn off ALL loads when rig is not in use, easiest solution is to install a disconnect switch between battery and 12v bus. The “phantom” loads are not wired to the existing disconnect switch. My battery has an I/O switch, so it serves the same purpose as a dedicated disconnect. When I shut off my battery, no juice goes to bus.

[BobC]

A multimeter with a clamp-on Ammeter probe that reads DC is a valuable tool for tracking down and measuring parasitic and other loads. With the clamp, you don't need to disconnect a wire to read amps, just clamp the probe around the wire in question. Here's a link to what I purchased (it comes with leads and will perform all the usual multimeter functions):

https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

Less expensive ones are available but be sure that the specs specifically state that the clamp measures DC amps. Some of the descriptions on Amazon and other sites can be misleading.

Note the difference between the above and this, less expensive look-alike:

https://www.amazon.com/AstroAI-Multi...57&sr=1-3&th=1

If you read the description and look at the switch settings, you'll see that it only reads AC current (amps) whereas mine clearly reads both AC and DC current.

Also, here's a link to a Winnebago "Service Tip" on parasitic loads:

https://www.winnebago.com/Files/File...%20Systems.pdf

[cruizerEd]

Does battleborn have a bluetooth app that lets you read the BMS info? They should. Get the app and see what the batteries recorded. It sounds to me like your batteries went into protection mode but that is just a guess.

Your description isn't consistent with a low voltage cut off but that would be my guess given that you don't seem to have done a thorough job of configuring the system yet.

The main inconsistency is the fact that they charged back so fast, 300AH of flat LiFEP04 even is being charged with Flood lead acid battery setting wouldn't have "finished" that quickly.