Solar not charging the lithium battery

Bill&Suze

We were on a trip two weeks ago and had stopped at a Finger Lakes winery on a sunny day. When we returned to our car I checked the Victron Connect app and saw that there were zero watts of solar reported being produced, even though we had parked in full sun. I checked the SMP disconnect and saw that a wire had pulled out of its eyelet connector and figured that fixing the issue would be easy - simply get the wire crimped back into its connector. But it wasn't so.

The yellow disconnect indicator on the SMP was not visible and I can't remember if I pushed the blue button or not before loosening the hex nut to remove the eyelet connector. I managed to get the wire pushed back into its hole in the connector and crimped it down as best I could with pliers, then put the connector back on the threaded stud on the right hand side of the SMP and tightened the hex nut. Since then there continues to be little to no PV production per the Smartsolar app. I've checked and rechecked the various fuses that are obviously involved in solar to battery charging - the 30 amp at the SMP, the 30 amp at the MPPT and the 30 and 3 amp fuses at the battery. They're all intact.

Today I checked voltage at the SMP 30 amp fuse shown in the photo and saw 10v DC on a multimeter. For the past two weeks the MPPT has only displayed a slowly blinking blue Bulk indicator light. Testing current at the MPPT, I read 13v plus or minus at the Battery connections and zero at the PV connections. Should I interpret that to mean that there is no solar voltage getting to the SMMT? Could the SMP have failed, perhaps related to the disconnected wire? Is the MPPT not functioning? The battery SOC is slowly dwindling, down now to 72% at about 13.2v. I'll plug into shore power this evening to charge the battery.

If anyone has some insight into what's going I'd appreciate hearing your thoughts.

pthomas745

Good for the hard multimetering work! 

What does your Victron app say?  If the battery (what battery setup do you have?) is showing fully charged, the solar will have nothing to do, and the PV readout you are seeing is normal. 

Grumpy_G

Let me try to decipher this. The "SMP" is the 50A marine breaker above the battery switch (made by "Mechanical Products", with a globe logo). If the lights and other 12V devices work when not connected to shore power, then the breaker is fine. Measuring 13ish volts at the battery connections of the solar charge controller ("MPPT" refers to the method of controlling charging) indicates the fuse in the picture is good.  I don't know how you measured the voltage at the fuse so the 10V reading might be misleading. 0 V at the PV connections could mean the connections from the panel(s) are bad or the fuse is blown, but also that the controller has detected an error and shorted the input (error 38 or 39). The victron app should show that but in any case you can try to reset the controller by removing the fuse in the picture and the fuse in the wiring from the solar panel, then reinstall in that order. 

rfuss928

Did you check this fuse?  It is kind of hidden by the wiring and hard to see from above.  A small mirror may help...

Bill&Suze

pthomas745 said:

Good for the hard multimetering work! 

What does your Victron app say?  If the battery (what battery setup do you have?) is showing fully charged, the solar will have nothing to do, and the PV readout you are seeing is normal. 

I have one Battle Born 100 amp/hr lithium battery connected to the Victron Smartshunt and of course to the Victron MPPT charger. The Smartshunt Status pane of the Victron app has consistently shown a decreasing battery voltage, dropping from around 13.6v when last fully charged 11 days ago when we returned to today's 13.2v. The Smartsolar Status pane has generally continued to show zero watts and zero volts generated over the last 10 days, although the History page of the Smartsolar pane shows that there has been some PV generation, for instance 10Wh today, zero yesterday, 10Wh the day before (see attached screen shots), even though the Status pane typically shows zero watts and zero volts at that moment when I launch the app. I agree that if the battery were fully charged, the PV readout would show little or no charging activity but the battery has not been fully charged. I haven't had it connected to shore power since we returned from the trip.

If you look at the screen shots you'll see that 11 days ago, October 1, we had normal solar charging which included 56 minutes of float time and 15 minutes of absorption time along with 4hr 20min of bulk time. This was the day that we visited the vineyard and I found the disconnected wire. Every day after that shows varying Wh and volts generated but starting 10 days ago the app shows no float or absorption periods, just bulk periods. this is why I'm concerned that perhaps the disconnected wire triggered some malfunction in the solar charging function.

11 days ago was normal - float, absorption and bulk periods indicated by 3 segment column


Here's 11 days ago expanded to show values of the 3 segments


10 days ago - only bulk time shown, continuing through today


Today

pthomas745

The Victron solar controller and the App can go a bit haywire if the battery is not connected properly. Have you tried your meter on the battery itself and checked the status?

I would also check the fuse RFuss pointed to.  It is "supposed" to be a reverse polarity protection fuse.  If the loose wire you found on the circuit breaker managed to short itself out on something, that protection fuse may be blown. 

The way the solar controller is connected to the battery is also important. If the controller lost contact with the battery during the time the wire was loose, and then while you were checking the other fuses, these controllers have been known to get "lost".  The controllers receive power from the solar panels and the battery.  The proper way to connect the controller is to connect the battery wiring to the controller first...allow the controller to "read" the battery state of charge, and then connect the solar panels to the controller.

You could: check that fuse on the solar controller.  See if that is good. It is a 20 amp.

If it is good: pull the fuse at the solar controller coming in from the solar panels.  It is on the positive solar wire next to the controller.

Pull the fuse from the positive wire that runs from the solar controller to the battery.  ( I believe this will be at the battery distribution block or close to it).  Let the controller totally shut down.  Reconnect the fuse for the battery to the solar controller.  Watch the Victron and see that it senses the battery state of charge.  Then connect the solar panel fuse at the controller.

This is the section from the Victron Controller manual that explains this. (Pages 13-14. You can skip the parts about the "DC loads" and the "VE Direct Port."

https://www.victronenergy.com/upload/documents/Manual_SmartSolar_MPPT_75-10_up_to_100-20/29694-MPPT_solar_charger_manual-pdf-en.pdf#UUID-f5e2207d-d1de-00d2-9bcc-90f24eca4fb4

Bill&Suze

rfuss928 said:

Did you check this fuse?  It is kind of hidden by the wiring and hard to see from above.  A small mirror may help...

@rf@rfuss928, it may be that your diagram showing the fuse location is for an older controller? Mine is quite different on the underside. I think that now the MPPT controller has an external 30amp fuse. I've taken several screen shots that hopefully show this.

Bottom of unit, wiring only - red & white on the left to battery, green & white on right go to PV terminals


The 2 green wires go to a 30 amp fuse which doesn't look blown

Grumpy_G

 Your solar controller is a different model with higher current rating, the picture showing the fuse location is for the lower power models. Pull the fuse out of the holder and check with your multimeter in ohm/resistance setting. Do the same with the fuse near the breaker. "Doesn't look blown" can be misleading. 

pthomas745

@Bill&Suze the fuse I was discussing in my earlier post about the fuse from the solar panels to the controller is the fuse there in your photo.

Thanks for pointing out the difference in your "newer" solar controller.  Either: Victron built the "reverse polarity" function onto the board for the controller (which is normal on different companies controllers), or...who knows.  But, obviously, yours is a newer model.

Bill&Suze

Grumpy_G said:

 Your solar controller is a different model with higher current rating, the picture showing the fuse location is for the lower power models. Pull the fuse out of the holder and check with your multimeter in ohm/resistance setting. Do the same with the fuse near the breaker. "Doesn't look blown" can be misleading. 

@Grumpy_G, I did as you suggested, pulled both fuses and also the 30 amp at the battery. All three test good. I set the multimeter resistance setting to 20K, checked that it is reading correctly at a value of one, crossed the leads and saw a value of zero, then tested each fuse. All showed 0.00 indicating that they are still good.

@pthomas745, I have done several iterations of your suggestion to remove all power from the controller/charger by removing all fuses - the 30 amp at the battery, the 30 amp at the controller shown in my photo, and the 30 amp on the wire that became disconnected. It is this fuse that appears to totally shut down the controller. Then I installed the battery fuse first and looked for recognition by the controller but at each iteration that I've done, the Victron Connect app shows nothing coming to life in the Smartsolar portion of the window. It's as if there's no device to recognize the battery. The Smartshunt portion displays normally.

Next step was to install the fuse at the controller but still nothing displayed for the Smartsolar portion. Finally I installed the fuse at the disconnected wire and then the Smartsolar readout appeared, but still without any indication of solar activity. The History page for today shows no bar graph, 0Wh for yield, 0W for P max and .2v for V max. It's as if the panels are not generating power - or the controller can't recognize it.

I've had the camper parked in the sun all morning and have been running the roof fan and several lights to put a load on the battery, trying to drain it down from the full charge it got last night on shore power, but if past history when I let the battery drain to 72% SOC is any indication and solar never showed signs of life, I can't help wondering if the controller needs to be replaced. I mentioned earlier that I tested voltage at the fuse holder on the disconnected wire and saw 10v by touching each contact in the holder with multimeter leads. I was in the shade then two days ago. Also, when I reinsert the fuse there's generally a bit of sparking which would seem to indicate that there is power coming from the panels. Maybe time to order a new controller? What do you think?

Grumpy_G

While electronics do fail it is fairly rare, especially with devices that are designed for rough operating conditions. I've seen this so often on automotive forums where somebody concludes the PCM is bad just to be back a week later after replacing the expensive part and the problem still isn't fixed. 
If you measured voltage across the contacts in the fuse holder near the breaker it does not yield any useful information. 
To make sure the panels are ok try the following: Remove the fuse for the panels near the solar controller, then measure voltage between the - terminal at the controller and the contact in the fuse holder that goes towards the panels. In sunlight you should see close to 25V. 

Bill&Suze

Grumpy_G said:

While electronics do fail it is fairly rare, especially with devices that are designed for rough operating conditions. I've seen this so often on automotive forums where somebody concludes the PCM is bad just to be back a week later after replacing the expensive part and the problem still isn't fixed. 
If you measured voltage across the contacts in the fuse holder near the breaker it does not yield any useful information. 
To make sure the panels are ok try the following: Remove the fuse for the panels near the solar controller, then measure voltage between the - terminal at the controller and the contact in the fuse holder that goes towards the panels. In sunlight you should see close to 25V. 

Thank you for sticking with this issue, I'd be flailing around without someone's help.

Just did it and saw 17.3v with panels shaded. That jibes with what the app shows for today's max voltage, but there's still no Wh yield being recorded. Any other tests you can think of to verify controller state of health?

elbolillo

Does your install have a Smart Shunt installed?

Bill&Suze

elbolillo said:

Does your install have a Smart Shunt installed?

Hi @elbolillo, yes, a smart shunt was installed by nuCamp and provides battery data.

Grumpy_G

The Victron solar chargers have a quirk where the solar panel voltage needs to be 5V higher than the battery voltage before they start charging. Once it starts charging the difference can be as small as 1V. So with 13.22V on the battery side the panels need to put out at least 18.22V to begin charging. 

Bill&Suze

Grumpy_G said:

The Victron solar chargers have a quirk where the solar panel voltage needs to be 5V higher than the battery voltage before they start charging. Once it starts charging the difference can be as small as 1V. So with 13.22V on the battery side the panels need to put out at least 18.22V to begin charging. 

Yes, you are correct. I remember @pthomas745 mentioning that in several threads and regarding my issue also I think. What is telling, though, is that on several days following the day I repaired the disconnected wire there was sufficient voltage generated to successfully charge the battery but its SOC slowly and continuously  dropped. Take a look above where I attached screen shots of the SmartSolar history graphs. At the "11 days ago" column there was enough voltage generated to charge the battery and enable it to enter absorption and then float modes. Starting with "10 days ago" and every day since the graphs show no absorption or float modes occurring. In spite of sufficient voltage indicated on many of those days, the fact of the matter is that the battery SOC continued to drop from 100% when we returned on 10/3 to 72% yesterday, 10/11. Some graphs may indicate some bulk mode activity but never absorption or float, and the SmartSolar page of the app consistently shows real time wattage generation as zero. Prior to 10/1 I would see varying values for instant wattage, even early morning or at sunset but since then it's invariably zero.

Marceline

Bill&Suze said:

We were on a trip two weeks ago and had stopped at a Finger Lakes winery on a sunny day. When we returned to our car I checked the Victron Connect app and saw that there were zero watts of solar reported being produced, even though we had parked in full sun. I checked the SMP disconnect and saw that a wire had pulled out of its eyelet connector and figured that fixing the issue would be easy - simply get the wire crimped back into its connector. But it wasn't so.

....

If anyone has some insight into what's going I'd appreciate hearing your thoughts.

I don't know how NuCamp wires their solar systems, but...

I wired my own system for a portable panel with the same kind of breaker roughly based on this wiring diagram from Sunpowered Yachts.

https://www.sunpoweredyachts.com/product-page/2x-100-watt-bundle

I have a breaker resembling yours between the solar controller and the battery, and I have just one positive line to the solar panel, and one positive line to the controller. I deviated slightly from the Sunpowered drawing by adding a blade fuse on the line between the SAE port for my external solar panel and the controller.

I'm not sure where your two positive lines on the top (right) side of the breaker are going. Why do you have a fused line going to the breaker (the breaker itself is a fuse)? Have you traced all three pos lines to see where they're going?

pthomas745

@Bill&Suze to separate out which component is not working, you could detach the solar cable input from the panels and test their voltage separately.  If the panels are putting out their proper voltage (around 20V or so) and the controller isn't reacting to that, then the controller would be suspect.

I know this is a pain to diagnose.  The Victrons are nice, but when I've broken controllers before (I have a Hall of Fame of them) they at least had a simple display that just quit functioning.  The Victron's silly blinking lights will probably work even if the board inside is fried!

Bill&Suze

Thanks @pthomas745, I think that what you've suggested trying is what @Grumpy_G also suggested yesterday. He said "To make sure the panels are ok try the following: Remove the fuse for the panels near the solar controller, then measure voltage between the - terminal at the controller and the contact in the fuse holder that goes towards the panels. In sunlight you should see close to 25V." I took this to mean the minus terminal of the PV connections and the hot side of the fuse holder. Yesterday I measured 17.3V from shaded panels. I repeated the measurement today and saw just under 14V but today is much cloudier than yesterday. At any rate, the panels appear to be delivering voltage to the controller but it is apparently not then charging the battery. I've been suspecting that the controller is kaput for several days and am just about ready to buy a replacement but have held off, waiting to see if forum members can add further insight into why the battery isn't being charged. I've appreciated your input all along. Can you expand on your comment about a Hall of Fame of broken controllers? What events led to needing to replace them?

rfuss928

This is the correct manual for the Victron Smart Solar 100/30 & 100/50.  I think this is the type unit in the Black Canyon.  Section 8 is a thorough troubleshooting guide.
https://www.victronenergy.com/upload/documents/Manual_SmartSolar_MPPT_100-30__100-50/29694-MPPT_solar_charger_manual-pdf-en.pdf

Bill&Suze

rfuss928 said:

This is the correct manual for the Victron Smart Solar 100/30 & 100/50.  I think this is the type unit in the Black Canyon.  Section 8 is a thorough troubleshooting guide.
https://www.victronenergy.com/upload/documents/Manual_SmartSolar_MPPT_100-30__100-50/29694-MPPT_solar_charger_manual-pdf-en.pdf

Thanks @r@rfuss928, I skimmed through troubleshooting. There's a lot to try to digest.

rfuss928

That controller has many more features and user controls compared to the lower power Victron MPPT controllers common in most of our T@Bs.  Lots of "automatic" settings and control options not present on the 75/10 thru 100/20 models.
Good luck...

Bill&Suze

The issue of solar panels not charging the battery has apparently been solved. I threw in the towel, admitted defeat in trying to solve on my own and returned the camper to the dealer. It took a day for their technician to determine that the two panels on the roof have failed. He plugged in a panel the dealer has and the battery began charging. I have my fingers crossed that this is indeed the problem but it is certainly believable, since every day that I checked the PV connections at the controller with a multimeter there was consistently little to no voltage indicated. The problem started October 1 but I let it drag on, trying to diagnose myself and even getting Victron involved when I suspected the controller to have failed. Dealer says probably three weeks to process the warranty with nuCamp and wait for shipment of new panels that the dealer will install. I want to get the camper back and covered so I'm hoping that serious snow holds off until later in December!

pthomas745

@Bill&Suze you did everything you could.  Replacing the roof panels is a big job, so checking every possible thing was the way to go.

Bill&Suze

Thanks @pthomas745, I appreciate that.