SOC vs Voltage and Solar issues

Stilley
Stilley Member Posts: 15
in Battery/Electrical & Solar
Alrighty, asking this group for any advice because I think I’ve read enough forums and I’m not really getting anywhere

Happy 4th! Hope everyone enjoyed it! 

Here’s a bit of a timeline and I’ll put a TLDR at the bottom. We have a new 2025 Tab 360

We drove out to the Sawtooths on Thursday morning last week, set up camp, didn’t really feel the need to check out battery life on our camper bc the solar usually does wonders on drives so we figured it was full. The voltage also read 13V.

Woke up Friday am at 4:00 to the fridge blinking night mode assuming the battery was getting low, we turned down the fridge and at 5 am the Tab powered off completely - at that point I looked and our voltage was at 10.7 (didn’t check the state of charge). A bit caught off guard bc we’ve never had this happen as the solar keeps us pretty full. This trip we only had the fridge running over night, other trips we’ve had the heat, fridge, and charging ports used and no issues so this was concerning. 

 *we did have a torrential downpour for a few hours from 4 am - 9 am - weather impact? 

…Plugged the camper into the generator to give it a boost and unplugged it to see if it was still holding a charge (this Is before I learned how to read the victron app for state of charge) and it was powering stuff just fine. Almost like it needed a jump start? Went to Check the Victron app again and I’m now only seeing the Smartshunt and no solar. Waited a bit bc it was a gloomy day. Ended up plugging the camper into the generator to get it to 95% SOC and turned it off.  

Saturday- battery was fine all Friday night-sat. We left for a 7 hour hike, figured we’d let the solar charge for the day to see if it’s working. We got back and the SOC had decreased so we knew it wasn’t working (usually the solar would keep the life at ~90%, with our fridge on, it was at ~77%) and again our voltage was low at 10.7. We checked the fuses on the battery, #6 “The power converter and heating pads” was blinking red so we unplugged and plugged it back in (is that bad?) and the blinking red stopped but maybe that has something to do with the solar? We looked under the bed at the smartshunt and unplugged a fuse and plugged it back in and for a split second it showed up on Victron but went away. 

….I’m rambling..

TLDR To my point now, I’m still not seeing the solar on the victron app, I’m wondering why our battery did die overnight (was it not actually charging during our drive) and how would I check to see if the solar is working or not. And maybe what the blinking red was for the power convertor, heating pad fuse. Is there a connection feom battery to the solar that I should look at? 

PS. I’ve done everything from uninstalling the app, I’m the only one that has it connected, I forgot the device and added it again.. pretty much everything.  

Edit to add: we’re driving home and our battery life keeps decreasing so I think it’s confirmed the solar isn’t working so what should we look for? Also the battery voltage is showing 13.31, should this be lower if the battery life is like 40%?
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  • elbolillo
    elbolillo Member Posts: 560
    @Stilley What battery do you have installed in your Tab? Capacity?  Do you have an inverter?

    _____________________________________________________
    Ken / 2023 Tab 400 “La Bolita” (39,000+ miles) / 2024 Toyota Sequoia

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  • elbolillo
    elbolillo Member Posts: 560
    edited July 2025
    This is a handy chart for LiFePo4. 


    _____________________________________________________
    Ken / 2023 Tab 400 “La Bolita” (39,000+ miles) / 2024 Toyota Sequoia

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  • Stilley
    Stilley Member Posts: 15
    elbolillo said:
    @Stilley What battery do you have installed in your Tab? Capacity?  Do you have an inverter?
    We have the factory battery and inverter 
    • 270Ah 12-volt Lithium Battery Bank with Internal Heat
    • 3,000-watt MultiPlus Inverter/Charger
    I’m finding this thread quite insightful - https://tab-rv.vanillacommunity.com/discussion/19413/lithium-charging-question-newbie-solved/p1

    Our wires are set up exactly as the posters were and Nucamp confirmed that there’s were incorrectly wired thus giving a false reading in the victron app. It doesn’t really solve the fact the solar disappeared from our app (and is now impossible to pair again) and how our battery drained so quickly over night but it’s a start I guess! 
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  • Stilley
    Stilley Member Posts: 15
    elbolillo said:
    This is a handy chart for LiFePo4. 


    Thank you! I’m starting to think our SOC was misreading based off of another thread here where the posters wires were set up incorrectly on their smart shunt (ours are identical to theirs and Nucamp confirmed theirs were wired incorrectly). Going to maybe rewire and sync the app or just go off of the panel and chart here. Maybe simple is better here 
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  • pthomas745
    pthomas745 Administrator, Moderator Posts: 4,579
    edited July 2025
    Lots to digest here.  Were the battery heaters "on"?  What exactly was "blinking red"?  An LED next to a fuse in the converter? 
    If the battery heaters are left on, they soak up quite a lot of power from the battery, with the kicker that this power usage is not monitored by the Shunt, since the heater switch is wired directly to the battery.  (This is assuming your 230 amp hour battery is wired the same way that the Battleborn batteries are: the heaters are wired directly to the battery.  Let me know if this is incorrect in your battery setup).  The Battleborn heaters use up about 1.6 amps per battery
    If your inverter was also on, that would be at least another 2 amp draw from the battery.  This would have been picked up by the shunt, so you may have seen current being drawn from the battery.
    The Victron solar controllers are very sensitive to how they are connected to the battery: the battery must be connected to the controller first, and the controller must be allowed to "read" the battery voltage.  The solar panels (or any other charger) is then connected after the battery.  You mention "unplugged a fuse"......which one?  If you disconnected the fuse for the battery to the solar controller, this might be the reason the Victron bluetooth has simply stopped working.  Sort out exactly what fuse you pulled (it may be hard to tell!) but, in any case: you should be able to "reset/restart" the controller with the proper connection sequence: battery first, then solar. (There is a fuse at the solar controller for the incoming cable from the panel).  
    Last, but not least: we see many lithium setups, right off the lot, that have the Victron device settings completely wrong.  If you can, show us the settings for your shunt, at least, and after you get your controller restarted, we can have a look at them, too.
    And: a multimeter would tell you a whole lot about the actual status of your battery in these situations.  "Chasing the Victrons" happens to a lot of owners for various reasons (failures, bad settings, loose wires) but a multimeter will at least give you a good picture of the actual state of charge of the battery.
    Edit: this is a Battleborn page that describes how to set up a "BMV", or the Victron Shunt.  This can work for any lithium battery, just plug in the numbers from your battery manufacturers instructions.
    This is the Battleborn page for how to set up the Smart Solar for proper lithium charging.
    2017 Outback
    Towed by 2014 Touareg TDi
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  • Stilley
    Stilley Member Posts: 15
    edited July 2025
    pthomas745 said:
    Lots to digest here.  Were the battery heaters "on"?  What exactly was "blinking red"?  An LED next to a fuse in the converter? 
    If the battery heaters are left on, they soak up quite a lot of power from the battery, with the kicker that this power usage is not monitored by the Shunt, since the heater switch is wired directly to the battery.  (This is assuming your 230 amp hour battery is wired the same way that the Battleborn batteries are: the heaters are wired directly to the battery.  Let me know if this is incorrect in your battery setup).  The Battleborn heaters use up about 1.6 amps per battery
    If your inverter was also on, that would be at least another 2 amp draw from the battery.  This would have been picked up by the shunt, so you may have seen current being drawn from the battery.
    The Victron solar controllers are very sensitive to how they are connected to the battery: the battery must be connected to the controller first, and the controller must be allowed to "read" the battery voltage.  The solar panels (or any other charger) is then connected after the battery.  You mention "unplugged a fuse"......which one?  If you disconnected the fuse for the battery to the solar controller, this might be the reason the Victron bluetooth has simply stopped working.  Sort out exactly what fuse you pulled (it may be hard to tell!) but, in any case: you should be able to "reset/restart" the controller with the proper connection sequence: battery first, then solar. (There is a fuse at the solar controller for the incoming cable from the panel).  
    Last, but not least: we see many lithium setups, right off the lot, that have the Victron device settings completely wrong.  If you can, show us the settings for your shunt, at least, and after you get your controller restarted, we can have a look at them, too.
    And: a multimeter would tell you a whole lot about the actual status of your battery in these situations.  "Chasing the Victrons" happens to a lot of owners for various reasons (failures, bad settings, loose wires) but a multimeter will at least give you a good picture of the actual state of charge of the battery.
    Edit: this is a Battleborn page that describes how to set up a "BMV", or the Victron Shunt.  This can work for any lithium battery, just plug in the numbers from your battery manufacturers instructions.
    This is the Battleborn page for how to set up the Smart Solar for proper lithium charging.
    A lot to digest for sure, so sorry for the wall of text, a lot happened and I feel like it’s all somehow connected so I figured I would put as much information in here as I possibly could! 

    Thanks for your response! The battery heaters weren’t on and what was blinking red was the fuse next to the line that said “power converter and heating pad.”

    I linked a thread in my other response stating that possibly the wires at the solar controller are not hooked up properly, I’m wondering if that would solve the whole SOC vs Voltage issue? 

    We’ll go out there today to try what you recommend with resetting the solar! Instructions seem easy enough. We don’t have a multimeter so we’ll give that a go as well. 

    Edit: when you say inverter are you meaning my generator or is there an inverter in the camper itself? Assuming there is but wouldn’t know how to turn that off/on. Sorry, I’m very much a newbie here 
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  • jkjenn
    jkjenn Member Posts: 6,423
    edited July 2025
    I am going out on a limb and suspect two things are going on...maybe more, but let's eliminate these as possibilities, first. 

    Battery monitor is resetting to 100% and giving you a false reading on your SOC. This would happen if you ran the battery all of the way down and it got enough charge to reset. Verify this by:

    In the VictronConnect App, access your BMS, or SmartShunt (same device.)

    1. Click the gear icon in the top right corner.
    2. Select Battery. 
    3. Scroll down to "Battery SOC on reset".  
    4. Confirm if it says, "Set to 100%". 
     

    If it does, I recommend changing that setting to "Clear", which will force th eBMS to wait until it gets a proper reading to give you a SOC.


    The second thing I am wondering if the Multiplus (inverter) is in the "On" mode versus the "Charge Only" mode?

    https://youtube.com/shorts/uLrBArL090w

    2021 T@b 320 Boondock "Mattie Ross" | 2021 T@b Nights: 239 | Total nights in a T@b 455 | 2022 Jeep Grand Cherokee L Overland | T@b owner since 2014

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  • Stilley
    Stilley Member Posts: 15
    jkjenn said:
    I am going out on a limb and suspect two things are going on...maybe more, but let's eliminate these as possibilities, first. 

    Battery monitor is resetting to 100% and giving you a false reading on your SOC. This would happen if you ran the battery all of the way down and it got enough charge to reset. Verify this by:

    In the VictronConnect App, access your BMS, or SmartShunt (same device.)

    1. Click the gear icon in the top right corner.
    2. Select Battery. 
    3. Scroll down to "Battery SOC on reset".  
    4. Confirm if it says, "Set to 100%". 
     

    If it does, I recommend changing that setting to "Clear", which will force th eBMS to wait until it gets a proper reading to give you a SOC.


    The second thing I am wondering if the Multiplus (inverter) is in the "On" mode versus the "Charge Only" mode?

    https://youtube.com/shorts/uLrBArL090w
    Hi Jenn! We have watched many of your videos :) thanks for your reply! 

    I will go ahead and reset the SOC to clear and see if that helps! 

    Based on your video, it looks like I may not have an inverter after all? I do not have that device in the Victron app. All I’m seeing is the smartshunt 
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  • jkjenn
    jkjenn Member Posts: 6,423
    If you have the lithium package, you have the Mulitiplus (which includes the Inverter.) IT can be manually operated as well, and I believe it can be found under the bed on the driver side - that's where it is on the prototype. The only other option might be if the dealer installed the 270ah Gamechanger battery and not nuCamp, then they might hae included another inverter? I don't think that is highly likely, though.

    2021 T@b 320 Boondock "Mattie Ross" | 2021 T@b Nights: 239 | Total nights in a T@b 455 | 2022 Jeep Grand Cherokee L Overland | T@b owner since 2014

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  • elbolillo
    elbolillo Member Posts: 560
    Stilley said:
    elbolillo said:
    @Stilley What battery do you have installed in your Tab? Capacity?  Do you have an inverter?
    We have the factory battery and inverter 
    • 270Ah 12-volt Lithium Battery Bank with Internal Heat
    • 3,000-watt MultiPlus Inverter/Charger
    I’m finding this thread quite insightful - https://tab-rv.vanillacommunity.com/discussion/19413/lithium-charging-question-newbie-solved/p1

    Our wires are set up exactly as the posters were and Nucamp confirmed that there’s were incorrectly wired thus giving a false reading in the victron app. It doesn’t really solve the fact the solar disappeared from our app (and is now impossible to pair again) and how our battery drained so quickly over night but it’s a start I guess! 
    To accurately help you we need to confirm that you in fact have the 270ah battery and Victron inverter.

    _____________________________________________________
    Ken / 2023 Tab 400 “La Bolita” (39,000+ miles) / 2024 Toyota Sequoia

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  • Stilley
    Stilley Member Posts: 15
    Ah, interesting. After searching the model number for the battery. It comes up as a 12 V 100ah (bb10012h). I can also confirm that based on the victron app. So we may not have an inverter after all. I’m including a photo of what’s under the drivers side bed, I’m not seeing any thing other than the smartshunt and controller. 

    Also: the controller is blinking slowly blue and the Smartshunt has a blinking Bluetooth button
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  • jkjenn
    jkjenn Member Posts: 6,423
    The Multiplus would be in one of the areas closer to the front on the driver side.

    2021 T@b 320 Boondock "Mattie Ross" | 2021 T@b Nights: 239 | Total nights in a T@b 455 | 2022 Jeep Grand Cherokee L Overland | T@b owner since 2014

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  • Stilley
    Stilley Member Posts: 15
    Okay, I did do some research and it looks like we do not have the lithium battery upgrade. It’s simply a convenience package, which includes the 100Ah 12 V lithium battery not the 270 Ah with MultiPlus, apologies for any confusion there! 
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  • elbolillo
    elbolillo Member Posts: 560
    Stilley said:
    Okay, I did do some research and it looks like we do not have the lithium battery upgrade. It’s simply a convenience package, which includes the 100Ah 12 V lithium battery not the 270 Ah with MultiPlus, apologies for any confusion there! 
    That makes sense. So are you now able to view both the smartshunt and the solar charger on the Victron app?

    _____________________________________________________
    Ken / 2023 Tab 400 “La Bolita” (39,000+ miles) / 2024 Toyota Sequoia

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  • Stilley
    Stilley Member Posts: 15
    edited July 2025
    I am currently only able to see and connect to the Smartshunt not the Solar on the app
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  • Grumpy_G
    Grumpy_G Member Posts: 745
    The Victron Smart Solar has a fuse to the left of the connections. Sometimes you have to remove and reinsert it to get the charger out of its funk. Check the fuse while you're at it. 
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  • Stilley
    Stilley Member Posts: 15
    An update! I pulled both fuses from the charger and basically reset the solar and it pulled up on my victron app finally!.. I did find that the solar was indeed working but not as well as other trips we’ve been on (we did have some inclement weather). I cleared the SOC so we’ll wait for that to sync when wits out of our garage. 

    Still curious why our battery powered off early Friday morning but could that just have been from us running the fridge during our drive and into the morning and using lights all Thursday night? We did have our camper plugged in all Wednesday night before our trip although it’s a house outlet (we use a surge protector), is that not ideal? 
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