8.7kW system coming Orange County, SoCal

[solarfrank]

You can't have more than 5250 W per string on Solar Edge Inverters , so if you like to use LG 300W you can have maximum 17 modules/string .

[s_man]

SolarEdge Site Designer

Thanks Frank for your input. I've just tried the software Site Designer from SolarEdge and it seems each roof that has a different orientation (South, West) has to use a different inverter. The SE10000 inverter allows 3 strings connected but all would have the same orientation. I know many of SolarEdge users has 2 different orientations. May I ask if you have the same case, do you have to have 1 inverter for each orientation or you could edit it someway? Thanks for your input!

[gvl]

SE 10k supports 2 strings. I suspect the difficulty maybe due to the shading of the panels due to roof pitch. There's a limit on the number of shaded panels in a string, once exceeded there will be no production on that string. If that is the case micros may be a better idea than 2 inverters.

Edit: you can have more than 2 strings per inverter, but they need to be connected in parallel using a combiner box as the inverter only has 2 pairs of DC terminals.

I've just looked through the installation guide, there's nothing about odd/even panel count restriction. All it says that strings can be of different lengths.

[gvl]

You can't have more than 5250 W per string on Solar Edge Inverters , so if you like to use LG 300W you can have maximum 17 modules/string .

Is this true? According to the specs the recommended max DC power for the 10kWh inverter is 12400W, and it is allowed to be oversized up to 135% depending on the average yearly temperature. Definitely more than 5250W per string.

[s_man]

SE 10k supports 2 strings. I suspect the difficulty maybe due to the shading of the panels due to roof pitch. There's a limit on the number of shaded panels in a string, once exceeded there will be no production on that string. If that is the case micros may be a better idea than 2 inverters.

Edit: you can have more than 2 strings per inverter, but they need to be connected in parallel using a combiner box as the inverter only has 2 pairs of DC terminals.

I've just looked through the installation guide, there's nothing about odd/even panel count restriction. All it says that strings can be of different lengths.

Thanks gvl for your input! I think the agent did not understand what the designer wanted to say. When I tried the Site Designer software from Solar Edge it seems the problem is whenever you try to make a system with different PV arrays that has different orientations then the software force you to choose 1 inverter for each of the PV arrays. So that's why I wondered if Solar Edge users here who has to set up with 2 different orientations has to use 2 inverters or not. The software does allow 3 strings (10,10,9) with same orientation connected to the 10kw inverter.

[gvl]

Thanks gvl for your input! I think the agent did not understand what the designer wanted to say. When I tried the Site Designer software from Solar Edge it seems the problem is whenever you try to make a system with different PV arrays that has different orientations then the software force you to choose 1 inverter for each of the PV arrays. So that's why I wondered if Solar Edge users here who has to set up with 2 different orientations has to use 2 inverters or not. The software does allow 3 strings (10,10,9) with same orientation connected to the 10kw inverter.

3 strings sounds familiar. My installer came with plans from the office to arrange the panels as 3 strings, but they quickly realized this was not going to work as the inverter only supports 2, so they wired the panels as 2 strings 15 each. I wonder if there is a bug in the Site Designer software or there is something I don't understand.

As for 2 inverters, if you determine it is a better approach, will this be extra $$$? I'd just go with micros if so. Also keep in mind if you plan to buy extended warranty for SE you will need to pay for each inverter separately, not much extra but still it is your money.

[solarfrank]

Solar Edge support max 5250 W/ string for systems larger than 10.5 KW you need to use 3 strings and combiner box.
SE said you can have minimum 8 modules same orientation on one string. You can have on one string modules in different orientation, in your case you can have 9 orientated E and 8 orientated W on the same string.

Regarding the software please read the disclaimer

You can SE technical support:

USA and Canada: 1 877 360 5292
Email: to support@solaredge.us.

[gvl]

I don't know if odd/even count of panels restriction per the installer is valid, but if not sounds like 1 inverter may work if s_man can fit 8 panels on the west side and have 2 strings with 16/13 panels.

Also I suspect the 5250 w/string limit is due to the input DC voltage restriction which is 500V for SE.

[solarfrank]

All the information are in Power Optimizer Specifications – P300 / P400 and 5250W it is for single phase inverter.

http://www.solaredge.us/files/pdfs/application_note_power-optimizer_P300_400_MAN-01-00173-1.0_Spec_na.pdf

[s_man]

Thanks gvl and Frank for your input! Yeah, the 5250w limit or 17 panels in my case is right. I've just called SolarEdge and they said it's just the Site Designer limitation that may not have options for different strings with different orientation for same inverter. They said I could do 2 strings with different orientations. So they suggested I use 9 panels of the West facing roof + 8 panels from the South facing roof into 1 string and 12 panels of the South facing roof in 1 string. They said I could use 3 strings but then I have to use a combiner box which cost more for me. I guest this installer really doesn't do much SolarEdge systems otherwise they may have seen this; that's what I was afraid of at first when then keep insisting on Enphase. Now I guess has to learn more about SolarEdge myself to make sure everything is right. Thanks all again for your information!

[gvl]

Here is another relevant document:

String Combiners in SolarEdge Systems

After reading it and assuming 8 panels will actually fit on the West side it looks like it is best to reduce the South-facing group to 21 panels, and wire them up into 2 strings 10/11 panels each, and have another string for the West facing section with 8 panels, and use a combiner box to tie them all together for a single-inverter scenario.

Edit: I guess with SE's blessing a combiner box isn't really necessary...

[OftheSeven]

Thanks gvl and Frank for your input! Yeah, the 5250w limit or 17 panels in my case is right. I've just called SolarEdge and they said it's just the Site Designer limitation that may not have options for different strings with different orientation for same inverter. They said I could do 2 strings with different orientations. So they suggested I use 9 panels of the West facing roof + 8 panels from the South facing roof into 1 string and 12 panels of the South facing roof in 1 string. They said I could use 3 strings but then I have to use a combiner box which cost more for me. I guest this installer really doesn't do much SolarEdge systems otherwise they may have seen this; that's what I was afraid of at first when then keep insisting on Enphase. Now I guess has to learn more about SolarEdge myself to make sure everything is right. Thanks all again for your information!

Any updates?

[s_man]

Any updates?

I have to contact them myself every 2 weeks to find out about what's going on. Now after almost 8 weeks, the salesman refer me to the guy who is in charge of the project and he told me he has like 10 other projects in line so mine may be another 4 weeks. Kind of disappointed because they originally promised me 4-6 weeks. Guess I won't have much of it for summer

[inmojo]

Hello! Could you please PM me Company B and C info? I'm in the Irvine area and am currently researching companies as well.

Thanks!

[LLtK]

s_man: I'm very interested in knowing the contractors B & C of your. Please PM me. Thank you.