Check these violations for me please

[Coppersmith]

I just looked at a solar installation and I saw what I think are several code violations. I would like to hear if you people agree.

(See drawing) It's a solar system with a large battery. The inverter has an emergency function where if the utility power is lost, a critical loads panel stays powered (from the battery). The critical loads were detached from the breakers in the main panels and connected to standard breakers in the critical panel. Circuits from both main panels were brought over into the one critical loads panel. Only the hots were brought over. The critical loads panel gets its neutral from the inverter (which is tied to the utility neutral). No neutrals from the main panels are being brought over.

Violation? - The circuit neutrals need to accompany the hots.
Violation? - The breakers in the critical loads panel need to be AFCI's (if required AFCI circuits) since the circuits were extended more than six feet.
Violation? - A ground wire needs to be in the conduits.

Also, one of the main panels has six hots going to the critical panel in a single conduit. If the neutrals are added, then this would be 12 CCC in a single conduit. IMHO, derating would be required unless these are broken into two conduits.

 

[jaggedben]

Agreed on your first two violations and on the derating if more than 24 inches. The conduits only need a ground wire if they do not qualify as EGCs themselves, although I think it is good practice to just always run one.

 

[pv_n00b]

To start, please never use "critical load panel". It's a backup load panel. Critical has a very specific definition you don't want to be tied to unless this is a hospital.
Typically the backup load panel will be fed by the inverter with two lines, a neutral, and a ground. The load circuits from the backup load panel go out as either two lines for 240V loads or a line and a neutral for 120V loads, and an EGC for either. It does not sound like that is happening here and it's not NEC compliant.
The AFCI requirements follow the NEC requirements for the circuits, it's not affected by the source being a backup load panel.
I'm not sure if there is a restriction in the NEC about using a panelboard as a pass-through for other conductors. I know in SWBDs you can't run conductors through a section if they don't land there without putting them in conduit.