Solar Not Charging New Lithium Battery (read: electrical amateur)

stevenbenoy

Hello Wise(r) Humans! 

Recently, attempted a Lithium upgrade via my local dealer for my 2021 Tab320 to allow for longer boondockin' yet still struggling (for the time being).

Its been to the shop 5+ times and still not functioning. Really hoping this community can help me with this mystery as I couldn't find another thread with the exact issue! 

• Existing Trailer + Solar Panel = 2021 NuCamp Tab320 (pic #1)

• New Battery = Battle Born LiFePO4 100ah 12v (pic #2) 

• New Converter = WFCO WF 8735-AD (pic #3) 

• New Shunt = Victron SmartShunt IP65 500A/50mV (pic #4) 

• Existing Controller = Victron SmartSolar MPPT 75/10 (pic #4)

• Device Screenshots =  (pic #5+)

jmcgonig

You are only getting 11W from your Solar, that's not even going to make up for what you are running.  That solar panel is going to be at full power to have a chance of charging your battery in addition to the normal load IMHO.

stevenbenoy

Thank you for such a fast response! That screenshot is capturing an overcast day (sorry!). Most days the controller registers well above 50W with no charge to the battery...

Marceline

stevenbenoy said:

Thank you for such a fast response! That screenshot is capturing an overcast day (sorry!). Most days the controller registers well above 50W with no charge to the battery...

I think that we'll have a better chance of helping you if can take a screenshot on a sunny day when you think that the solar panel should be sending power to the battery. Your screenshot 5.PNG makes it look like the controller is indeed sending power to the battery, if only a paltry amount. It shows that the controller is in bulk charge mode, which seems right. Go to the history tab for both the smart shunt and the solar controller and take screen shots of those so we can see what's happening over a number of days.

I believe that you have the Isotherm 2way fridge. Assuming that's correct, the fridge is your biggest power hog. Use the smarthsunt to track how much power is consumed when the fridge compressor kicks on. Pay attention to how long the compressor is running. It's important to initially cool the fridge from shore power, as the initial chill from ambient temperature consumes a large amount of power. If you don't have access to shore power, use dry ice or blocks of ice to initially cool the fridge from the ambient temperature to 40deg.

Yoshi_TAB

Hi,

If you look at the smart shunt screen shot , the current says -1.67.  Minus means that devices in your TAB are using more than what is being produced by solar.  So you are consuming more than producing.  You need to be on the positive side to make up what you consume (by fridge etc. ) to charge your battery.  Your solar is only producing 0.8  Depending on sun conditions you may be able to get it higher into the 2.5-3 range, but until then it does not appear that you are producing enough solar current to make up what you are consuming and then extra to charge your battery.  That is why many folks buy a second portable solar panel that can be turned and moved while the sun moves.  I’m out traveling but and don’t have access but there a some good you tube videos about how it all ties together.  I found them very helpful when learning about solar and charging a battery. 

pthomas745

"Local Dealer" may mean "Electrical Amateur" just like some of us.  I would go over your settings for you battery step by step, page by page, section by section.  For both the Shunt and the Solar controller.  Battleborn has a couple of pages that have specific step by step, section by section set up procedures. We have seen tons of badly configured Victron items.  These setups are complex, and it can/will overwhelm everyone.

This is the Smart Solar setup:

https://battlebornbatteries.com/programming-a-victron-smartsolar-charge-controller/

This is the Smart Shunt setup.

https://battlebornbatteries.com/faq-all-about-bmvs/

One more thing you could show us is your history page for the smart solar.

stevenbenoy

You are all the best Sadly, still stuck tho...

Updates:

• Audited shunt/solar setup to manufacturer recs
• Ensured solar power output with no/minimal battery impact (see screenshots)
• Reminded that I still have more learning to do

Any insight would be SO appreciated! 

• 

Marceline

The History tab for the SmartShunt with a daily view would provide more useful information, IMO. The timestamps and timeframes on the two TRENDS screenshots above are different (2 days vs 5 hours per bottom left of each screen), so it's hard look at one to see how it relates to the other. It's always best to compare apples to apples.

The shot on the left (covering 2 days) shows that ~48 hours earlier your battery was at full charge and then started dropping maybe about 3pm the day before. The shot on the right (covering a 5 hour period) seems to show that about 2 hours into that 5 hour time frame (maybe around 10am) your controller started sending power to the battery. It makes sense that the solar controller kicks in as the sky gets brighter.

My guess is that the solar production you're showing on the right (max 53 watts) corresponds to the slight upward bump in the shot on the left that nudged the SOC back up towards 65%. But for whatever reason, the solar controller only sent power to the battery for about 2 hrs in this 5 hour window.

Two unanswered questions: 

1. You need to figure out what's drawing down the battery relatively quickly (left chart (100% SOC to 60% SOC in ~24 hours). Did you turn on the fridge? Do you have an inverter turned on? Did you look at SmartShunt STATUS page to see exactly how much power was being drawn from the battery (especially at night when there's no solar production). Something is very steadily taking power from the battery.

2. What caused the solar controller to suddenly stop producing power at ~1:00pm (the line plunging straight down on the right chart)? Was something blocking the panel?

stevenbenoy

Marceline - my newest hero! If you or anyone helps me solve this, I'm sending you a gift!

Answers and Insights: 
1. Fridge is on, your correct - wanted to draw the battery to assess impact from solar
2. Due to the sun direction where parked, might be the reason? 
3. I can't speak to the small uptick on the left photo above 
4. Pics of longer (and identical) time frames of 14 days are included. NOTE: I do plug into shore power when it drops too low (reason for dramatic increases followed by dramatic decreases due to no charge AND fridge running) 

Marceline

As I mentioned in my last post, I think the History page would provide more useful information. What you’ve uploaded is the Trends view. 

History is more helpful because it shows actual numbers, not just a chart. This is all just simple math. You need to know how many amps are being drawn from the battery and how many amps are going into it. The Victron app will give you that data. The SmartShunt page will tell you the net gain/loss and the SmartSolar page will show what the controller is feeding to the battery. 

I’d start your experiment all over again.
1. Plug the T@B into shore power for a couple of days. 

2. Start the fridge and bring it down to 40deg with the T@B still plugged into shore power.
3. Put some cold stuff in the fridge, even water bottles are fine but whatever it is must be cold (do not put anything room temp in the fridge. 

4. Only after ensuring that your battery is fully charged AND the fridge is cold (40deg) and set to a medium setting AND the trailer is parked somewhere with sun exposure, unplug from shore power.

Use the “Status” view on the SmartShunt section of your Victron app to see how much power is being added or drawn from battery at any moment in time. Check periodically. If the number is negative, your solar isn’t keeping up with the fridge. It will of course be a negative number at night. If the trailer is in full sun, the number should be positive at least some of the day.

Look at the HISTORY page see the daily or hourly input/output. Based on the SmartSolar screen cap you posted it’s clear that the solar controller is feeding power into the battery, but it’s impossible to see any actual numbers from the screenshot you’ve posted. 

Here’s a link to the manual for the Victron Connect app. I think you’ll save yourself a lot of trouble if you read through it, paying attention to the parts that explain the different views and the information they present. 

https://www.victronenergy.com/upload/documents/VictronConnect_Manual/8778-VictronConnect_manual-pdf-en.pdf

If you search YouTube for “Victron Connect” there are a lot of videos explaining how the
app works.