This is why I like to use high quality DC circuit breakers instead of just a switch

Hi I have read a lot of the replys to the video, I hane not seen it mentioned that there are two cables going through the plastic gland, I can not uncerstand why, as it would be so easy to use a second gland,

First issue is that the isolator is installed on the roof of all places. Best way is to just run cables down to a DC combiner DB downstairs, then install the isolator down there with a DC rated breaker, fuses, surge arrestors. Never install the isolator on the roof…

Check fuses and Iso to make sure they're rated for your voltage. Lots of fuses say 20amp etc but then 200volts. Noark are 450v max. On a sunny day you can soon go past this voltage but still be under the 20amps. This trips sparky's up when only working with 240v.

Brilliant video, thanks man. This is very dangerous indeed. These things are unsafe in common. There is no way to keep those boxes dry, they should be installed INSIDE and not under cover of a panel!

Apparently it is NOT recommended to use external DC isolators in the UK after recent house fires anymore, I believe the newer inverters have them built in. That one your showing looks to have had water ingress. Cheers.

I have all wires seperated in individual waterproof boxes for plus and minus that are installed under the roof so they cant even touch each other and then have a disconnect switch in a dry secure area where its the only point they come together. I dont even need to climb up for anything

Its funny how NZ rules say NO roof top isolator, But the Aus rules say yes

Great video. Subscribed… look forward to more videos

Good info.

Will be doing a ground mount but the disconnects will be on wood posts. Might be a good idea to put fire proof material under them. The indoor parts will be on cement board.

I am guessing the higher the string voltage the higher the chance of arcing ??? I have a few small systems as I love playing with solar (very addictive hobby) and I live off grid out in the Wheatbelt. My 48 volt system runs a panel voltage of 110 volts open circuit and my 24 volt system runs a panel voltage of 87 VOC. I am running the same disconnect switches you show in this video. I often wonder how I would go in the event of a component failure and DC arcing at 110 volts Vs the higher voltages the grid tie systems work at ?? Would be interesting in hearing your thoughts. Loving you vids 👍

Thanks Jason, I'm a Firie in FNQ and been to many a DC isolator fire. I think the legislation has changed (in QLD anyway) in that a rooftop isolator is now an option rather than a requirement. I'd like to remove mine at some stage, am hopefully getting additional panels to support off grid EV charging shortly so hope to get rid of it then :)

See I’ve been having people ask me why I don’t mount my solar panels on my roof. Well for one you can’t tell if it’s on fire till it’s too late unless someone sees it in time to inform you. In my opinion it’s a fire hazard being that they are mounted on top of flammable materials such as shingles with tar that burns very hot once ignited along with the wood underneath. So that’s my reason for not mounting solar panels on top of my roof. In my opinion panels should have individual fuses/breakers to prevent such occurrences

I only have one roof to isolator. The other strings don't. I will get rid of that one. I need to remove panels anyway as there is an insulation failure. Don't need an isolator on the roof anymore

Roof grid-tie voltages are high and the roof is high, it is indeed dangerous and best left to professionals, but smaller lower volt solar systems built closer to the ground or on RVs can be managed by amatuers that pay attention to what they are doing and get quality components such as MC4 connectors all from the same manufacturer so they match. (MC4 is a weather proof rating, not a size) On the ground all you need is an MC4 to un- plug for power isolation. Ironic that a safety feature like a solar panel isolator would be the weak spot that causes problems.

They should made it mandatory to install that in a firebox like the lithium batteries on the 787 wouldnt had that much on to the system.

I have had that happen to me on a 1000v 25kw system that thing went up in flame like a Christians tree

Does the polarity depend on the LOAD side? I.E. does the polarity depend on the direction of the load ?

Begs the question, why no dc circuit breakers in a supposedly professional install?

roof top solar isolators should be checked every two years as a isolator will create to much resistance when water entry and weather conditions. they should not be on the roof they should be under cover, the government rules need to change roof top isolators are dangerous and great more problems then there worth

THIS IS ELECTRICITY! There are tons of DIY solar panel videos on youtube making people think this is so easy--not to mention one slip and fall can kill a person or disable them for life. DIY will definitely invalidate any roof warranty, and homeowner's insurance can drop the owner.

I had 24 solar panels catch fire on the roof of my shed yesterday lucky it didn’t Burn my shed to the ground and everything inside it

These are the consequences of keep buying and promoting cheap switches that aren´t suitable to withstand thermal requirements on roof top application. Even CEC knows about this situation and problem was not related to breaking capacity but thermal capacity, nevertheless market keep buying the same switch technology of blade contacts that can´t guarantee contact pressure, thus overheating then fire.

I have been researching this and have found that this is a very common problem world wide. It seems that more often the switch is to blame than installation error. DC voltage is much more prone to arching than AC. I am skeptical about using them all together. Thank you for this public announcement.

My brother... had you ever heard of such thing named tarp? :)) You can use one or two to shut down the solar panels. One laminated hdpe tarp enough to cover the entire array should be way less that $100. Hooks above and some counterweights below. Stop whining about diyers and handymen when you (propose to) unplug mc4 connectors on a potentially loaded array.

why not use a DC circuit breaker instead of an isolator

Weird that you would do a video, blame someone else for setting it up wrong that then not show us how you set it up correctly and instead tell us to get a solar person to do it. Fail!

A isolator is not rated to break current First switch the load off No current flow, isolate A circuit breaker rated to break current at a certain voltage is a different story

DC ISOLATOR SWITHC UP THERE?!? IN BETWEEN THE SOLAR PANELS?!? WHAT THE FLUCK!

An electrician knows more about connecting electrical cables better than a solar guy who only knows how to install solar panels in a straight line. You are blaming the installer and not the quality of the equipment and you don't know what is the cause of the fire.