Grounding roof top solar array questions

[keaton85]

This will be an easy one for you guys, I've been reading and kinda going in circles.

Pertaining to EGC from the panels to the GTI, my installation is as follows:

10KW array --> #12 run via FMC inside home --> to GTI --> #6 run via conduit to 200A subpanel (#10 EGC for this run)

Now, i get the bare #6 on the roof for bonding, but some are saying never run the EGC inside the house raceway. so is it like this:

#6 bonding--> #6 outside of house to ground rod --> back up to GTI and then to subpanel?

Trying to wrap my head around the EGC for the panels so I can order the cable.

[Mike 134]

Following 2020 NEC in my location, #6 solid under the panels bonding the Iron ridge rails together. At the J box under the lowest panel transitioned everything to #10 THHN, DC wiring and grounding conductor. Ran 3/4" metal conduit (with the ground wire inside of it) to the inverter landing the grounding wire on the ground bar provided. Then continued the AC wiring and ground wire back to the house panel.

Have no idea why someone would say not to run the ground wire inside conduit but after working 38 years in the electrical trade feeding my family, I've seen a lot of handyman crap.

[MGE]

Lets start here.
EGC = Electrical Grounding Conductor?
GTI = Ya got me? Inverter?
FMC = Not a clue? MC cable? ? metal conduit?

Spell it out to make it easier for us old guys.

The bare #6 can run exposed on roof to bond framework, panels, as needed, Then connect internally to j-box with the wiring from your MSP (main service panel) like the way I did that?
Just remember you have to crimp your ground/bonding wire connection and no wire nuts for the ground wires anyway.

Eh what do I know. Turned out from apprenticeship back in 1984 IBEW #569.

[keaton85]

Equipment Ground Conductor
Grid-tie Inverter
Flexible Metal Conduit

[Mike 134]

Lets start here.


Eh what do I know. Turned out from apprenticeship back in 1984 IBEW #569.

IBEW 134 here 1981 bit older than you

[Mike 134]

This will be an easy one for you guys, I've been reading and kinda going in circles.

Pertaining to EGC from the panels to the GTI, my installation is as follows:

10KW array --> #12 run via FMC inside home --> to GTI --> #6 run via conduit to 200A subpanel (#10 EGC for this run)

Now, i get the bare #6 on the roof for bonding, but some are saying never run the EGC inside the house raceway. so is it like this:

#6 bonding--> #6 outside of house to ground rod --> back up to GTI and then to subpanel?

Trying to wrap my head around the EGC for the panels so I can order the cable.

Your inverter only puts out 16 amps on a 10KW system?

[keaton85]

Your inverter only puts out 16 amps on a 10KW system?

the #12s are from the array at around 11A at 400V, with a round trip distance of about 50ft.

the invert does 42A so that’s the #6 going to the panel.