8400w Grid Tie System - Kit or piece it together?

[Mike90250]

Please check out Leapfrog / Skip wiring vs plain Daisy-Chain wire

http://solarprofessional.com/articles/design-installation/cost-saving-pv-source-circuit-wiring-method

[Mr4btTahoe]

Please check out Leapfrog / Skip wiring vs plain Daisy-Chain wire
http://solarprofessional.com/article...-wiring-method

Looks complicating... really isn't though and would save a good bit on wiring. Thanks!

[foo1bar]

I was thinking that the cables on the panels themselves wouldn't be long enough to go panel to panel... so that makes sense.

They are often long enough you can do "skip wiring" or "leapfrog wiring" when wiring a row of panels laid out portrait orientation.

Doing that style usually means less length in the "home run" wires

give me the potential to add an SB3.0 down the road if I need more juice... and still be within the 10k and under regulations.

7.7 + 3.0 is more than 10.

[littleharbor]

Thanks bud! Greatly appreciate the input.


As far as wire runs.. the longest run will be ~55' (from the far end of the array back to the inverter. I'll be sure to run everything in conduit post array.


Thanks again!

You may be able to incorporate leapfrog wiring to shorten your home run to the inverter. Don't think this will work with landscape orientation. I don't recall your layout.
Leapfrog wiring of series wired panels.jpg

[DanS26]

OP....You are a true DIY'er.....Good luck but I don't think you will need it.

[ButchDeal]

Looks like I'll be over voltage in the cold months. The inverter I want to go with has the ability to run 3 strings... so I could just wire them up as 3 strings of 8 couldn't I?

Would make wire routing on the rack a bit more complicated, but would keep me within specs.

After toying with solardesigntool.com the SB7.0 seems to be a better fit when using 3 strings of 8 panels which would save me a bit of cost... and give me the potential to add an SB3.0 down the road if I need more juice... and still be within the 10k and under regulations.

That would be over 10kw. Yu would be better off installing something like the SolarEdge SE10000 inverter. Yu can easily add modules to the solaredge system especially pv modules that do not match because you can no longer get onesie match.

[Mr4btTahoe]

They are often long enough you can do "skip wiring" or "leapfrog wiring" when wiring a row of panels laid out portrait orientation.

Doing that style usually means less length in the "home run" wires



7.7 + 3.0 is more than 10.

7.0 + 3.0 is 10. However, I re-read their cut off and it says below 10k.. 10k+ and its a hassle.

I'd have to go with something like a 2.8kw inverter which I'm not sure if anyone makes a grid-tie that small.

I'll do "skip" wiring more then likely.

As far as going with the SolarEdge, they look to make great stuff but it would put me over budget I think. I'll look into it a bit.

[Mr4btTahoe]

Well... looks like I've got somewhat of a plan in mind and the list about buttoned up. I'll turn this more into a project thread when I start ordering parts hopefully at the end of the month.

Dropping a couple trees this weekend to get the shade off the roof of the shop. Closing on our other house hopefully in the next week or 2 and then it is game on!

Thanks for the help guys. I'll post up with plenty of pictures as this progresses.

[littleharbor]

Best of luck to you. looking forward to the photos.

[ImInPhxAZ]

Solaredge has a 6800 and a 3000 inverter in the hdwave series. You don't have to use the optimizers.

[ButchDeal]

Solaredge has a 6800 and a 3000 inverter in the hdwave series.

OP is in US I believe. Which means that SolarEdge has HDWave models of 3kW, 3.8kW, 5kW, 6kW, 7.6kW and 10kW..... Not 6.8kW

It would be far smarter to install the SE10000H than two separate inverters

https://www.solaredge.com/sites/default/files/se-hd-wave-single-phase-inverter-datasheet-na.pdf

You don't have to use the optimizers.

you DO need to install the optimizers with SolarEdge.

[DanS26]

IMHO two matched inverters are better than one large inverter. Why?........because you now can compare on an hourly, daily, monthly basis the production of each inverter against each other. You will know immediately if there is a problem in any panel or inverter by comparing outputs in real time.

This is true even if you have different orientations for each array and inverter since you will over time know and calculate the production differences between inverters.

This is not theory but real world experience talking.

[ButchDeal]

IMHO two matched inverters are better than one large inverter. Why?........because you now can compare on an hourly, daily, monthly basis the production of each inverter against each other. You will know immediately if there is a problem in any panel or inverter by comparing outputs in real time.

This is true even if you have different orientations for each array and inverter since you will over time know and calculate the production differences between inverters.

This is not theory but real world experience talking.

Yes but if you have an optimized system like SolarEdge you can compare ever pv module voltage, amps, production to others and to past results
plus you get more production from single inverter with multiple azimuths optimized then separate inverters as you can get to running voltage more easily on poor light conditions.

[DanS26]

Yes but if you have an optimized system like SolarEdge you can compare ever pv module voltage, amps, production to others and to past results
plus you get more production from single inverter with multiple azimuths optimized then separate inverters as you can get to running voltage more easily on poor light conditions.

Yes but if you have a problem in that particular inverter (unless it is catastrophic) you will not know it maybe for months or years. The panel output reporting could look normal but actual inverter output could be abnormal without anyway of knowing.

[ButchDeal]

Yes but if you have a problem in that particular inverter (unless it is catastrophic) you will not know it maybe for months or years. The panel output reporting could look normal but actual inverter output could be abnormal without anyway of knowing.

Except there is inverter output reporting as well. Would be easy to tell from all the automated reports that the optimizers do not equate to inverter input or output.