I'm purchasing a house with an attached garage, and will be adding a
subpanel for use as a shop. The garage is already insulated and
drywalled, so I'll be running conduit (most likely EMT).
The most-filled run will have three 20A 120V circuits for outlets wired
with #12, and 2 30A circuits for 240V wired with #10. (One 240V for the
dust collector, and one for everything else.)
I'm currently planning to run a single #10 ground wire (bare or green)
to ground everything on this run. I think this meets code, but I'd like
confirmation. (I'm in Canada so it's CEC rather than NEC, but I wanted
to get a general idea if I'm in the ballpark.)
Assuming the above is okay, I'll have 11 wires in that conduit. Given
that I'm allowed 11 #10 wires in a 3/4" conduit, does that sound like a
reasonable conduit fill? Max spacing between conduit openings will be
about 10 ft.
Since this is a one-man shop I'll only ever be using two tools at once,
maybe three if someone is helping. I'm working on the assumption that
my load diversity is enough that I can use the 70% ampacity derate for
10 conductors in a conduit. Is this reasonable, or do I have to go down
to the 50% derate? Should I go with two 1/2" conduits instead of a
Finally, what's the best way to pull this given that the various wires
are going to different places, and one of the 240V circuits is going
right to the end? Do I pull one section at a time with all the wires
for that section?