Solar install turning out really bad - looking for some help/advice please.

[Ian S]

That is exactly why they cannot allow it. Any change to the components invalidates the testing done for UL listing. So SolarEdge could conceivably tell you that it is OK to change the terminal block as long as you deface the UL listing mark and remove the SolarEdge name from the assembly. Which would not make the inspector happy.

Exactly right. Once a component or system has been UL listed, you can't change it without going through the testing again. Maybe Solaredge could help educate the inspectors. After all, it's in their interest not to have their systems misunderstood by the powers that be.

[HX_Guy]

That is exactly why they cannot allow it. Any change to the components invalidates the testing done for UL listing. So SolarEdge could conceivably tell you that it is OK to change the terminal block as long as you deface the UL listing mark and remove the SolarEdge name from the assembly. Which would not make the inspector happy.

In practicality though really, what in the world could the different terminal block do that's unsafe? I mean you could probably use a freaking Polaris wire connector block in there and it would be safe. The inspector doesn't know that the terminal block was swapped out, and it would match the permit without having to go through the whole hassle of resubmitting it.

[inetdog]

... why it would be an issue to use a different terminal block aside that it wasn't tested by SolarEdge.

That is exactly why they cannot allow it. Any change to the components invalidates the testing done for UL listing. So SolarEdge could conceivably tell you that it is OK to change the terminal block as long as you deface the UL listing mark and remove the SolarEdge name from the assembly. Which would not make the inspector happy.

[HX_Guy]

What a cluster &^%$! So I called the city to ask them what the procedure is if we need to make revision to the permit. $150 fee, resubmit new pages for only the pages that have changes, and 5 day turn around time...not too bad overall. That's the good news.

The bad news is that the city people are idiots and they don't understand how this SolarEdge system works, which is why the permit shows #2 wire. With a traditional system, once you take into account what the array amperage would be, and calculate for the 125% safety and then the temperature derate factor (.85 here), I guess a #2 wire would be necessary. That is only if you were to count each wire as "hot", which in a ungrounded system they are, but that's addressed in the next point. SolarEdge isn't a traditional system and the conductors will never have more than 34.5A running through them...the city for some reason doesn't understand or believe that.

So that means if we redo the permit, we need to also educate the city on how this system works, or appeal their decision until we get to someone who does understand.

Ok...so then stick to the permit right? Problem there again is that the inverter input will only accept #6 wire and SolarEdge is saying you absolutely cannot change out the terminal blocks as the whole assembly is UL listed in the configuration it came in. AWESOME! Honestly I'm not even sure how much that would come into play...there is no reason I can think of (but maybe some else can?) why it would be an issue to use a different terminal block aside that it wasn't tested by SolarEdge.

[HX_Guy]

I'll check on the permit when I get back home to see what the temp used in the design is.

[SunEagle]

There will be a temperature correction for anything more than 30 deg, which is too low of a temp for an attic in AZ. The design temps used in the permit originally are probably still good choices, but if I recall correctly, even with those corrections 2 AWG is overkill. If HX_Guy can post the design temps from his permit, it will save digging through the threads and getting a magnifying glass out to figure it out.

Edit: And yes, although I think I would be capable of installing my own system, I think the money spent hiring an good installer is worth it.

Yeah the #2 is overkill and now requires modifications to the termination points at the inverter as well as pulling that wire through the attic. Seems like a lot of work to satisfy an "over" design.

[sensij]

The conduit runs out the bottom of the combiner box, then down into the attic so shouldn't need to derate the wires.

There will be a temperature correction for anything more than 30 deg, which is too low of a temp for an attic in AZ. The design temps used in the permit originally are probably still good choices, but if I recall correctly, even with those corrections 2 AWG is overkill. If HX_Guy can post the design temps from his permit, it will save digging through the threads and getting a magnifying glass out to figure it out.

Edit: And yes, although I think I would be capable of installing my own system, I think the money spent hiring an good installer is worth it.

[SunEagle]

These wires are going into conduit that is on top of the roof?
I think they are - which means you have to derate the current capacity.
And how much you derate depends on temp - which depends on how far off roof surface the conduit is. And also what the design temp is for your location.

The conduit runs out the bottom of the combiner box, then down into the attic so shouldn't need to derate the wires.

[Living Large]

I have been watching this thread and the others from HX_Guy since the beginning. I'm a do it yourself kind of guy. I've built additions, all phases of construction, roofing, garages, sheds, hardwood flooring, installed complete kitchens, installed furnaces, wiring and plumbing for entire house, etc... After watching this story unfold, I will say hiring competent solar installer to do the solar install was the best $10,000 I ever spent. Hopefully HX_Guy can put this all behind him soon.

I haven't installed a system yet, but everything else you said I agree with. Everyone could see this #2 vs #6 thing coming, since he mentioned the discrepancy. It's a darned shame. I hate to say this, I learned a lot though his problems. Hang in there, HX_Guy - you're almost there.

EDITWell, I did not do some of those things. Kitchen install and entire house plumbing. I'm glad I called a professional for my plumbing, because I had no clue about venting guidelines, test procedures, etc.

[HX_Guy]

These are actually thru the attic, not on the roof. Do they still need to be derated?

[foo1bar]

Definitely do not need #2, that's way overkill (good for 115A @ 75º C). The inverter will never "request" more than 34.5A per SolarEdge, even with the NEC 125% rule, that's 43.13A. 6AWG wire is good to 65A @ 75ºC.

These wires are going into conduit that is on top of the roof?
I think they are - which means you have to derate the current capacity.
And how much you derate depends on temp - which depends on how far off roof surface the conduit is. And also what the design temp is for your location.

[SunEagle]

I have been watching this thread and the others from HX_Guy since the beginning. I'm a do it yourself kind of guy. I've built additions, all phases of construction, roofing, garages, sheds, hardwood flooring, installed complete kitchens, installed furnaces, wiring and plumbing for entire house, etc... After watching this story unfold, I will say hiring competent solar installer to do the solar install was the best $10,000 I ever spent. Hopefully HX_Guy can put this all behind him soon.

I agree with you. Sometimes it is worth spending your hard earned money on a proficient Contractor then saving a few bucks.

I also believe that HX_Guy has done an outstanding job fixing the issues left by his Installer and will end up with a class act solar installation.

[Mb190e]

I have been watching this thread and the others from HX_Guy since the beginning. I'm a do it yourself kind of guy. I've built additions, all phases of construction, roofing, garages, sheds, hardwood flooring, installed complete kitchens, installed furnaces, wiring and plumbing for entire house, etc... After watching this story unfold, I will say hiring competent solar installer to do the solar install was the best $10,000 I ever spent. Hopefully HX_Guy can put this all behind him soon.

[HX_Guy]

OK. I wasn't sure of the wire size for the green ground wire & red DC wire. Just wanted to make sure you didn't have to replace that conduit in your attic.

They are both #10 THWN-2 wire.

[SunEagle]

According to the conduit fill calculator I used, it comes out to 31% conduit fill, which I believe is fine per NEC. Plus it's what the permit says.

OK. I wasn't sure of the wire size for the green ground wire & red DC wire. Just wanted to make sure you didn't have to replace that conduit in your attic.