Solar Panel Fail?

[KR.]

Posting in case there might be an alternative explanation to my probable solar panel failure.
I mainly only use the van for one night at a time, as such I don't pay that much attention to my power setup other than a couple of glances at the Victron app to see how it's doing.
Given the strange phenomena of bright sunshine today I thought I'd see how my solar was performing.
It was flatlining, here's the history.






I've spent a few hours reading up on possible causes and trying to work out what's wrong. My guess is it failed 6 days ago as per history screenshots above, although the Vmax yesterday confuses me. I checked the panel plus/minus at the Victron but getting zero, also the case on checking the panel junction box.

I've had the panel 4 years. One more thing of relevance is the Victron MPPT is blinking blue LED only which points to fuses, PV panel, wiring but nothing visibly wrong there that I can see.
Thoughts?

 

[TallPaul_S]

Worth having a read through this thread

Need some help with Solar issue

Replaced my solar panel and ran new cables in using mc4 connections. At each stage I checked for volts all good at 20-22v all the way to the final crimped tail ends. However on plugging said ends into the Victron mppt the controller is not doing anything and showing no activity , charger is off...

www.t6forum.com

We went through the full gamut of possible issues and troubleshooting!

What does your MPPT show for voltage and amps coming into the charge controller?

Blinking blue on the Victron just means there's not enough PV to allow charging, which doesn't help really.

If you can disconnect the panel via the MC4 connectors or the input into the Victron, then test the open circuit voltage and the short circuit current, this will tell us if your panel is alive or dead.

Edit: just seen your last picture - that does look like dead panel.

 

[KR.]

It does look dead doesn't it. More money, sigh

 

[Dellmassive]

Try this test again with the panel disconnected from the victron mppt.

If you still get 0v then it's looking like the panel is open circuit/dead.

If you get voltage, around 18v odd then we can look more into it.

But the screen shots look like a failed panel.

 

[KR.]

You might be onto something there - MPPT disconnected.

 

[TallPaul_S]

Yes, so that's the open curtain voltage, only tested with nothing connected to the panel.

Test the Amps in the same way while it's disconnected.

Panel might be ok then? Have you checked the fuse in the MPPT? To the left of the inputs on the bottom (normally, depending what MPPT it is).

 

[KR.]

I've no meter to check amps (working away from home). Solar voltage down to 15v and the battery voltage up and down.


But battery sense monitor pretty stable, switched a few things on to see how it would affect solar draw.



Victron LED's were steady blue, then steady yellow, now back to steady blue - bulk/float/bulk.Victron app not showing any rise above 0W.
A couple of weird things going on...

 

[Dellmassive]

View attachment 240716

You might be onto something there - MPPT disconnected.

So either the panel is faulty and unable to deliver any amps to the mppt.... Dropping voltage to zero as the mppt loads the circuit.

Or the mppt has a short on the PV input... causing volt drop across the panel.


As above you can try a Amps test on the panel and see what you're get.

 

[KR.]

I checked again this morning with some, weak, sun on the panels. I've left fridge on while it's parked up at work and check what happens.

I also note this :


Those greyed out periods, what's happening there? My other thoughts are that
1. The battery is nearly always at a full charge, I'm not a heavy power user and have a DC-DC charger as well.
2. Yesterday was probably the warmest day of the year so far, the panel was hot, hard to keep my hand on it, it's fixed directly onto my poptop with no airgap that I can see.
3. Connections into the MPPT are untidy and I will get them crimped for a cleaner connection.
4. There are fuses in the system but on the battery end, but going by above all is okay in that regard.
5. It might be a 160W panel but I think the highest I've seen it is maybe 60W.
6. My clamp meter is at home but I'll check my 'normal' digimeter and try rechecking open cct current.

Thanks for all pointers so far!

 

[KR.]

Van hasn't moved, fridge still running but solar gone again. Frustrating.

 

[KR.]

 

[Dellmassive]

Looks like panel has failed.

Micro cracks on the busbars.

Sun heats up panel causing thermal expansion.

Got a mobile panel to test?

Or connect a small battery to the PV input to see if you get a response from the controller .

Ie

100w Renogy portable suitcase panel.?

 

[KR.]

Yes, it's pointing to failure when heated up. I've no other battery/panel to try on the PV input side, just a Noco powerpack.
Looks like it's some cheesewire, plastic scraping tool, WD40 and elbow grease followed by a new Renogy 200w flex panel and Sikaflex. I'm work, away on holiday then working again so time to order stuff before doing the work.

 

[TallPaul_S]

Yes, it's pointing to failure when heated up. I've no other battery/panel to try on the PV input side, just a Noco powerpack.
Looks like it's some cheesewire, plastic scraping tool, WD40 and elbow grease followed by a new Renogy 200w flex panel and Sikaflex. I'm work, away on holiday then working again so time to order stuff before doing the work.

If you go for another semi flexible panel, put down a wrap on the pop top first then put the panel on that, it'll make taking it off when it fails again easier! It seems to be when, not if a semi flexible panel fails!

 

[Dellmassive]

And pack out the ridge's, that's normally what causes the failures.

Top ridge bonded, but trough not, that causes uneven expansion of the panel,

And some sagging in the trough...

@Rids done a good job of building up the troughs using open cell plastic sheets cut down to size....

I remember him showing it on a thread somewhere.

 

[KR.]

I think wrapping is better than not wrapping but adds another layer of complexity (pardon the pun). I'm tempted to put a new panel on top of the old one. Not the best but it will still work. Won't it ...

 

[roadtripper]

I think wrapping is better than not wrapping but adds another layer of complexity (pardon the pun). I'm tempted to put a new panel on top of the old one. Not the best but it will still work. Won't it ...

I think the risk there is your new panel security at 70mph is depending on the bonding between the layers of your old panel.

And the other popular failure of the flexible panels is layer delamination...

 

[KR.]

Yes, I see what you mean. I've ordered a Renogy 200W panel and see how it goes when it arrives. It's getting the time to do things at the moment. FWIW Renogy 200W Flex panel going for £180 on the Renogy site v £210 on Amazon. See, now I feel like I've saved money

 

[meza]

Sorry @KR., Renogy 200W Flex panels are down to £163 inc vat & delivery with a voucher code currently!

VC9OFF

 

[Eclipse Custom Vans]

Looks like panel has failed.

Micro cracks on the busbars.

Sun heats up panel causing thermal expansion.

Got a mobile panel to test?

Or connect a small battery to the PV input to see if you get a response from the controller .

Ie

100w Renogy portable suitcase panel.?

Exactly this, weve had many failures with panels, hopefully the new technology is more robust.