Solar Panels poor performance

lisawarninger

I have a brand new 2024 Tab 400 Boondock with the lithium upgrade. 

There should be 620 watts of solar panels on the roof… and indeed there are 2 solar panels mounted up there. However the output of those panels in full sun is rarely over 100watts. My PMax average is probably right around 80 watts. 

I park east to west in full sun so if the sun is out… it’s hitting the panels directly. 

I have a portable 100 watt panel I use to power a portable fridge and it often outperforms these panels. I am getting power from them, so they are both working, they just don’t work very well. 

If you have the package with these upgrades what has your PMax been? 

Have you added extra portable panels with the solar port? How did that change your PMax. 

rfuss928

What is your battery state of charge?

pthomas745

"Lithium Upgrade" with: 4 lithiums?  2 lithiums?  We can get quite confused by what battery setup you might have.

We have also seen plenty of Victron setups that are very wrong, mostly because they are set to charge AGM batteries, not lithium.  You should try to check the battery settings on the SmartController and make sure you have a proper charging profile for lithiums.

And, as rfuss928 said: if your batteries are mostly charged, your solar input would not need to be the maximum that that big panel set might be able to put out.

B0atguy

The 2024 packages can be a little confusing , even for the dealers . 
Having 2 solar panels, 620w on a 2024 400 would make you think it has the "Lithium Package" upgrade ........wrong . Having the 2nd solar panel just means that it has the "Black Canyon" package . The "Lithium" package is different , and you might have the lithium package with or without the 2nd solar panel (Black Canyon Package) . Why on earth NuCamp would NOT install the 2nd solar panel with the lithium package upgrade is a mystery . Only the Black Canyon gets the 2nd solar panel. 

Now you may also have the lithium package along with the black canyon package , or the dealer / sales person misunderstood that having 1 lithium battleborn battery (standard on 2024 400 ), meant it has "lithium package" . 

The "Lithium" option package is an approx $8,000.  upgrade so look in your sales contract to see if it does have the Lithium package upgrade . It already has the Black Canyon upgrade since you have a 2nd solar panel on a 400 . 

Here is an easier way to find out if you have the "Lithium" package . 
Make sure your 400 is unplugged from shore power . Does the microwave or A/C work ? 
If they do , you have the Lithium upgrade package , if not you probably dont . 

Also Solar charging can be a bit confusing as well . If your battery is fully charged (or almost) , it wont appear that the solar panels are charging at much watts .........because they dont need too. Its all in the settings on the Victron solar controller . 

Hope that helps ..........need some more info on if you actually have the Lithium package . 

ckjs

lisawarninger said:

I have a brand new 2024 Tab 400 Boondock with the lithium said:

…

There should be 620 watts of solar panels on the roof... My PMax average is probably right around 80 watts. 

I park east to west in full sun so if the sun is out… it’s hitting the panels directly. 

I have a portable 100 watt panel I use to power a portable fridge and it often outperforms these panels. …

That does seem a bit low, but solar panels only provide their rated power when they are pointed just right: lying in a flat plane perpendicular to the sun. Panels on a curved roof will never hit their peak power, nor will ones angled off-axis.

When placing portable panels, it is likely that you’re positioning them optimally, even without thinking too much about it.

My “330W” rooftop front & rear panels peak about 210 watts, on a midsummer noon. The low sun angle these days gets about half that. However over a full day I typically get 500-800 watt hours, with the front panel generating more when the sun is directly facing it, vice versa for the rear. 

Horigan

I would also check the power rating of the Victron solar charge controller.  They may have installed a lower wattage version than the panels can provide.  First, as mentioned above, I would confirm the controller has the correct battery settings and the battery is sufficiently discharged to require bulk charging.

lisawarninger

Hi Everyone! Just to clarify: I have a brand new 2024 Tab 400 with the Black Canyon Boondock and the Lithium Upgrade. 

So that means that it arrived from the factory with:
- 2 320 watt solar panels on the roof
- 4 100Ah 12-volt Battle Born lithium batteries 
- 3,000-watt Victron MultiPlus inverter charger
- Victron Smart shunt
- external solar port

and yes, I paid for all of it, and I knew exactly what I was purchasing and I unscrewed the boards on the bed to verify that all the batteries are there and the inverter and the smart shunt. 

I also understand that solar panels rarely get what they are rated for, especially if they’re curved and facing different directions, which I why I specifically orient my camper for the solar panels to receive maximum sun through the course of the day. 

I would think with 610 watts I’d get a higher Pmax, it seems low to me. So I wanted to see what others are getting with this same setup. 

My batteries are currently down to 30% so it should be charging as much as possible. If my batteries were fully charged, then of course the panels can’t add to a fully charged battery. 

I had to look up how to set up my settings inside the Victron app, because NuCamp didn’t include instructions on that. I’m fairly certain it’s set up correctly. 

More than anything I’m wondering what other people with this setup are experiencing and if external solar panels are helpful to be getting more charge into the batteries.

I’m in literal ideal conditions full sun at noon and I’m only getting 89 watts. 

lisawarninger

lisawarninger

Here’s the settings in Victron, hopefully the pictures come through in order… it just seems to me, that in full sun at noon, 620watts of solar panels should perform in the 400watt range  

do we know what the power rating of the solar charge controller nucamp installs is? Their setup is fairly sophisticated, so it would be strange if they somehow missed that step and we can’t actually use more than 200watts of solar.

pthomas745

@lisawarninger Thank you for the confirmations.  We often get confused by the "lithium packages". 

Your Victron solar controller type is listed in the "My Devices" screen shot: it is a 50 amp solar controller, which is proper for 620 watts of panels. Your settings are correct for lithiums, etc.

There are two separate readouts in your screen shots, ten minutes apart.

The first "Status" screen of the SmartSolar (at 12:35) does show only 89 watts, which, yes, would be quite low.

The "MyDevices" screen shot, taken 10 minutes later, (12:45)shows the SmartSolar putting out 174 watts.  This could be a passing cloud, etc., to make up for the differences. 

Is anything running in the trailer when the screen shots were taken.

In general, yes...if the sun is solid and the trailer pointed the "right" way, even 174 watts seems low.  In perfect lab conditions, a 100 watt solar panel "might" put out 8 amps. 

Grumpy_G

A couple of observations from the last screen shot:
The battery voltage at the shunt shows 13.21V. The ubiquitous LiFePo4 voltage charts put that at ~70% charge, not 30%. Has the shunt been properly "calibrated", a.k.a. set to 100% with known full batteries ? 
Also, the solar controller shows a battery voltage of 13.62V which is higher than the 13.21V the shunt and inverter are registering. Does the controller show its target voltage or actual voltage ? If there is a bad/high resistance connection between the controller and the batteries it will limit the current. 

Marceline

lisawarninger said:

Hi Everyone! Just to clarify: I have a brand new 2024 Tab 400 with the Black Canyon Boondock and the Lithium Upgrade. 

So that means that it arrived from the factory with:
- 2 320 watt solar panels on the roof
- 4 100Ah 12-volt Battle Born lithium batteries 
- 3,000-watt Victron MultiPlus inverter charger
- Victron Smart shunt
- external solar port

and yes, I paid for all of it, and I knew exactly what I was purchasing and I unscrewed the boards on the bed to verify that all the batteries are there and the inverter and the smart shunt. 

I also understand that solar panels rarely get what they are rated for, especially if they’re curved and facing different directions, which I why I specifically orient my camper for the solar panels to receive maximum sun through the course of the day. 

I would think with 610 watts I’d get a higher Pmax, it seems low to me. So I wanted to see what others are getting with this same setup. 

My batteries are currently down to 30% so it should be charging as much as possible. If my batteries were fully charged, then of course the panels can’t add to a fully charged battery. 

I had to look up how to set up my settings inside the Victron app, because NuCamp didn’t include instructions on that. I’m fairly certain it’s set up correctly. 

More than anything I’m wondering what other people with this setup are experiencing and if external solar panels are helpful to be getting more charge into the batteries.

I’m in literal ideal conditions full sun at noon and I’m only getting 89 watts. 

The output does seem low.

Can you click on the "History" and "Trends" tabs and post screenshots. 

I'm wondering if a) one of the panels isn't wired in correctly or 2) you don't actually have 2 320w panels up there.

One thing you might try: 

When the trailer is in full, midday sun, try disconnecting each panel separately. You could do this by pulling the fuse to each panel (one at a time), or if this isn't possible, you could just throw a heavy blanket over one panel and then the other. If the output changes when you "disconnect" one panel or the other, it would indicate that panel isn't wired correctly.

B0atguy

It is not a "rare" occurance to have a solar panel wired .........improperly or loose, bad connection , disconnected from NuCamp . There have been quite a few NuCamp fails on poor wiring on the solar panels, or even wired backwards . Our 2019 320 had such a bad solar wiring connection from the factory, that the panel barely out out any voltage . 
Check wiring and or panels . A blanket over a single panel 1 at a time is a good idea and an easy/quick way to check them each (while in full sun)  . 

 I think the panel input voltage is particularly low,  if in full sun . Those panels should be in the 22-24 volt range  . The controller would control the output, but panel input should be fairly consistent at 22-24 in full sun . The panels should be wired in parallel . Perhaps a bad connction point at that junction. 

Our 2024 does not have the Black Canyon Package, but does have the Lithium upgrade . WE have a single 310 panel on the roof, and we see 200+ watts of charge consistently (wish we had the 2nd 310 panel ) !