Recommendations for array wiring

[Jrv8984]

Recommendations for best way to create my strings (9 panels per string, 2 strings per mppt - Sol-ark 12k)

Arrays are facing south, those trees are to west running south west south

 

[timselectric]

Whatever is easiest for you is fine.
I also have 2 strings in parallel. I done mine like the first picture. I ran a single negative to the far end and combined the negatives from the two strings there. And then combined the positives at the close end.

 

[Jrv8984]

Whatever is easiest for you is fine.
I also have 2 strings in parallel. I done mine like the first picture. I ran a single negative to the far end and combined the negatives from the two strings there. And then combined the positives at the close end.

I'm not combining my strings, they go directly to the Inverter. If i do it like the second picture, it will keep my wire runs closer to the same length.

 

[Jrv8984]

Or i could do it like this, don't really think there is a benefit to it though.

 

[chrisski]

Depending how the west trees shade the array when the sun sets, a little more production will happen with #2 or #3.

With those only one string will be shaded. Depending on the way the trees shadow, you could get some extra production later in the afternoon as the sun sets. Could also be insignificant, all depends on the shade.

In a few years, the one tree in front of the array behind the sheep, how tall do you expect that? Appears that could effect production more than the others.

 

[Jrv8984]

I'm either going to move that tree or cut it down, its too close to my fence, and absolutely will cause shading.

 

[Jrv8984]

I'm thinking #2 is going to give me the best production in the afternoon!

 

[timselectric]

I'm not combining my strings

2 strings per mppt

Maybe I misunderstood?

 

[timselectric]

Either way.
Do whatever keeps the wiring short, neat, and easy.

 

[Jrv8984]

Inverters have 2 inputs per mppt, thats where they get combined.

 

[timselectric]

Inverters have 2 inputs per mppt, thats where they get combined.

Seems like a waste of wire. But maybe you have future plans that require doing this.

 

[Jrv8984]

I would have had to up size my wire to #6 to keep the voltage drop down. #8 was getting to close to 3% V loss for my liking.

Unless I'm mistaken, sol-ark 12k pv inputs limit you to #10 wire.

 

[timselectric]

I would have had to up size my wire to #6 to keep the voltage drop down. #8 was getting to close to 3% V loss for my liking.

Unless I'm mistaken, sol-ark 12k pv inputs limit you to #10 wire.

That makes sense. I wasn't aware of the #10 limitations.

 

[chrisski]

I would have had to up size my wire to #6 to keep the voltage drop down. #8 was getting to close to 3% V loss for my liking.

Unless I'm mistaken, sol-ark 12k pv inputs limit you to #10 wire.

I wonder why some manufacturers do not allow bigger input into an SCC to account for longer runs to help with voltage loss. I had the same limit with my Victron SCCs.

 

[timselectric]

You can run the larger conductor for the distance. And then reduce it before connecting to the SCC. This is common in the electrical field. Either with a pin reducer. Or just connecting to a smaller conductor right before.