Mike Marlow wrote:

Hey - you got it! Though 8 circuits would be crazy. You're looking at
maybe 2 circuits in your garage. Multiple switched runs, but all of them on
1 or 2 circuits.


Thank you for working your way through my previous post. I know I still
haven't mastered the jargon. "Switched" seems like an unlikely term for
what I think of as a "split". Hopefully we're talking about the same
thing. I've been saving "switching" for those things they put on the
walls!

To avoid "cycling the breakers", Lew advised running 12-3 from two 20
Amp breakers (it would not have occurred to me to do that).

I'm thinking of this lighting as a 4 by 4 grid (or so), with rows 4' apart:

L1 L2 L1 L2
L2 L1 L2 L1
L1 L2 L1 L2
L2 L1 L2 L1.

The 2 hots each split at the beginning of row 1, going down row 1 and
also to the beginning to row 2, similarly for common and ground, etc.

Intuitively, I'd use 12-3 romex to the first box in the attic, exiting
the box with 12-3 THHN for row 1 and row2 into the interior of the
garage. The longer I think about it, the more connections I want to
stuff into a junction box (but I have to consider the box capacity of
course).

It seems like a natural "4 (juntion) box" problem. I'm not yet sure
where to locate the other junction boxes after the first. I've
definitely made some progress in understanding this! 16 fixtures wired
in parallel Without a wad of wires! Cool! Beautiful even! : )

Bill