Why did this LG solar panel burn like this.

[@cods41]

Great video. I didn't think shading could have that much impact.

[@joondalupelectricalservice3201]

Yep sure does, I have learnt the hard way from my own installs years ago!

[@martinwinlow]

Another very good reason to use microinverters, then!

[@SmartEnergyLab]

I agree with you that shading has cause the problem, however, it shouldn't have been a problem if the bypass diodes were functioning. I guess they have failed in this panel and thus any shading will turn that part of the module into a load for the rest of the array, thus overheating the cells. It would be interesting to open up the junction box and test the bypass diodes if you can access them.

[@joondalupelectricalservice3201]

Hi Glenn Yes my understanding is the bipass diodes will only cope so long before failing. Whats your take on the middle section of the panels not suffering as much damage. I do have the panels still and will check the diodes for function.

[@SmartEnergyLab]

@@joondalupelectricalservice3201 Yes, some panel manufacturers state that they're not warranted for shade. I guess they're saying that the bypass diodes are not continuously rated. The reason only the shaded bottom right corner is badly effected is because that's where the shade was. A solar cell is a current source proportional to irradiance. If all of the array is in full sun and a few cells are shaded they will be reverse biased and act as a load, not a current source.

[@ltvtech]

Agree the effect of shading and even bird droppings is under estimated. Great video. Optimizer even better, Intelligent optimizer with shutdown like you have said. Thanks for your great videos

[@traceychrystal837]

Im learning so much through your videos, and I love your humour 🤓 🤪😂

[@junkerzn7312]

Normally the open-circuit voltage of a panel is maintained even in shade, and no reverse voltage or current would occur when the strings are paralleled and one string is partially shaded. It's contribution would drop to zero but that is all that should happen. The correct solution is to put each string on its own MPPT. Paralleling strings is really old-school.. . modern inverters have multiple MPPTs and nobody should be paralleling strings any more. Other solutions include having blocking diodes installed in the combiner box. And each string should also be individually fused anyway (the panels specify the fuse value required to avoid damage). If it was done right, the fuse should have blown. But again, the real solution in modern times is simply to not parallel strings at all and give each one its own MPPT. Then no blocking diodes are needed, no optimizers are needed, and everything is forward-biased regardless of the shading situation.

[@AndyM...]

Another great video Jason, I remember a year or so ago I went up on the roof to check my panels, at the time there was a bit of shading from the top of the ladder on to one of the panels, I put my hand on the shaded portion to see how much cooler the panel was, and it actually burnt my hand and left a mark for a week or so. I won't do that again. For larger scale shading do the bypass diodes compensate to some degree ?

[@joondalupelectricalservice3201]

Thats interesting to hear thanks Andy. Yes bipass diodes will partially help but they cant keep it up forever.

[@keything8487]

hello everyone ! thank you for the video. i am about to embark on my first personal home install journey. i would like to ask, how much shading was involved? were those panels in shade consistently, or 1-3 hours a day as the sun moved across the sky? also i was under the impression that a shaded panel would only bring down the other panels voltage of the string its on. would it help this issue, if the effected (shaded) panels were on their own mppt within the same inverter?

[@pariandangel]

What happens next? Is the panel still covered under warranty? Would this just keep becoming a rinse and repeat issue every few months even with a replacement panel until the trees are gone?

[@joondalupelectricalservice3201]

Hi, no not covered under warranty as they weren’t installed correctly. Tigo optimisers could be installed to avoid future panel failures.

[@alanblyde8502]

Interesting info, we’ve got 6 LG 335 watt panels on a tracker (no shading) I’ve seen them pumping out 2450 watts on a cool sunny day, shame they not making them anymore

[@joondalupelectricalservice3201]

It is a shame, good product that LG supported well unlike many other companies

[@Ale55andr082]

those shadows....

[@solargoat]

I thought you really couldn’t get reverse bias when you have bypass diodes… that’s crazy… maybe a tigo power optimizer?

[@solargoat]

Also this is my favorite YT channel. Would love to see more stuff

[@junkerzn7312]

Bypass diodes don't protect against reverse bias. The bypass diode is bypassing the cells in the forward direction. If reverse bias occurs, the bypass diode will block current going through itself, but will not prevent current from flowing in reverse through the cells. i.e. the bypass diode is in parallel with the cells. Bypass diodes allow a partially shaded panel to be bypassed at full current in the forward direction and for the string to continue to produce. Reverse bias only occurs if the partially shaded string is at a lower voltage than the fully operating string... but that normally doesn't happen because even shaded panels will sit at their open-circuit voltage with no current flowing through them. Actual blocking diodes are required at the combiner box to prevent reverse bias. But in modern times, the correct solution is to not parallel the strings at all and instead give each string its own MPPT. Then even the partially shaded string can do full production on all the non-shaded panels and the partially shaded panel would simply be in bypass.

[@NukeFPV]

Fark...... No wonder they stopped putting them up on your roof !! lol

[@cancerman3954]

So improper installation? I am going to install 6 340 watt panels should I wire them 3 in parallel and 3 in series?

[@safetyfirst1484]

Do 2 sets of 3 panels in series feeding into 2 separate MPPT's depending on the voltage and current ratings of your MPPT's.

[@margarita8442]

would use enphase micro inverters

[@aandscrawfoski]

Hi Jason, great real life video with no fake editing. Would a micro inverter system not have this problem? My System i wish to build - 4 x 570w solar panels connected to a Micro inverter 2800w 20v - 60v DC in and the output is 230v at 8 amps 50hz . The output from the micros(230v) go to a programable current switch mode battery charger - 230v input - 48v output across 4x 12v 200amp hour Carbon lead batts (48v).(fixed Controlled Current) The Micros are programable with current sensing. The Micros, to avoid issues would have Surge and RCBO 10 Amps Type B protection very close to inverter on the panel at the 230v output side. Micro input from the 4 panels would have 4 separate inline Fuses or 4 pole DC MCB(local panel Isolation) with their own surge protection on the DC side. Home power would come from High frequency sun ark mppt inverter units connected to the Battery 48v (non interference system as Switch Mode charger from Micros to Batts is galvanic and offers isolation as do the galvanic Micros). Note Money is not a problem only the high DC. All IEC approved gear NZ/AUS standard. Its against my religion to use high voltage DC due to the risk factor (hail , water , Mechanical insulation breakdown and the Idiot factor). Thanks Mate. Andrew NZ

[@joondalupelectricalservice3201]

Hey mate Yes micro’s on each panel would have the same immunity from the affect of shading 👍🏻

[@aandscrawfoski]

@@joondalupelectricalservice3201 Thanks for that.

[@aandscrawfoski]

@@joondalupelectricalservice3201 My brother is in Queensland, Would this system suggested be an acceptable solution on a MEN system using a compliant installer ? Thanks mate.

[@joondalupelectricalservice3201]

@@aandscrawfoski if its grid connect then the products used need to be approved and listed on the Clean Energy Council approved products list.

[@aandscrawfoski]

Hi Jason, It's off grid.. I will build one in kiwi land and test it first. We use redundancy systems in the telco world, so if he has any issues with micros , he could add an ACS to control micro to genny change over . Thanks mate. .

[@shyguykm]

Solar Optimizers per panel would help

[@joondalupelectricalservice3201]

They have since been installed 👍🏻

[@Cptnbond]

Such a bad installation, no distance around the panels to walk.