PV cables & grounds

[Gotshocked!]

I think I know the answers but I do not know, so if there's anyone out there that does and is willing to share their knowledge, thank you!

1. The wire that came connected to the solar panels is 12 awg. I'm using 10 awg to run panels to the inverter. From the inverter, it would be 10, then 12, then 10 then 12 then 10, the two 12's are the 2 rows of panels and the three 10's are the run to, the run from and the run in between the two rows of panels.

Can I use 10 awg wire to connect two halves of 1 string, right in the middle? I don't see why not.


2. My mini solar field ground is the original meter ground rod at the meter.

With 2 rows of panels and starting at the meter ground rod, should I take the 6 awg ground wire, hit all the panels and bring it back to the ground rod or dead end it at the last panel? I believe I should dead end it as I might be creating a ground loop if I bring it back.

 

[pvgirl]

1.Most likely ok, I can't say more without knowing panel specs/model and how they are wired(series/parallel), number wires in conduit, max ambient temperature.

2. Ground only needs to run one way, ground all the panels and mounts, and run with the PV wires back to inverter and connect to buildings ground system where convenient, doesn't need to be a the ground rod. 6AWG ground wire is only needed where the wire is exposed, can be reduced to smaller wire when in conduit.

 

[Jim in Florida]

Not enough information, wire size will depend on amperage and the panels will need bonding through your inverter that should be bonded back to your home ground through your main panel.

 

[Gotshocked!]

The 10 awg is more than sufficient for the strings. I'm wondering if it would be an issue to go from 10 to 12 then back to 10, then 12 again and finally 10 one last time. That's 5 transitions which is weird but the 10 is more than sufficient and the 12 is what's on the panel and I cannot change that. I suppose the only time this would be an issue would be if I installed something smaller than 12.

 

[pvgirl]

The 10 awg is more than sufficient for the strings. I'm wondering if it would be an issue to go from 10 to 12 then back to 10, then 12 again and finally 10 one last time. That's 5 transitions which is weird but the 10 is more than sufficient and the 12 is what's on the panel and I cannot change that. I suppose the only time this would be an issue would be if I installed something smaller than 12.

Going from 10 to 12 and back isn't an issue as long as the 12 AWG sections can handle the current.

 

[zanydroid]

I’m not sure #12 leads on the solar panels guarantees that you would be allowed to connect with #12 elsewhere. Depends on if the solar panels are required to follow the same wire gauge rules.

For Hoymiles microinverters each trunk tap is only sized to carry the current of one micro while the trunk is #10, so obviously special rules apply in that case

 

[Gotshocked!]

I get it. The 10 is good enough to carry power to and from, so it's good for the in-between as well. Thank you all, esp pvgirl.