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Tom Horne[_2_]

wrote:
I went to Lowe's today and discovered that it might actually be a
break even proposition to install a sub-panel instead of running 6 new
circuits back to the main, since I'll avoid about 150 total feet (over
6 circuits) of 12/2 cable. However, I saw only 100Amp, 125Amp, and
200Amp panels for sale. I was thinking I could find a 60A panel. One
of the 100A panels came in a contractor pack with the ground bar, 4
20A breakers, and one 30A double breaker for real cheap. So my
question is whether I can just buy a 100A panel, and connect it to a
40A or 60A breaker in the main panel, thereby effectively limiting it
to 60A. If I buy a main lug panel, do I then just connect the #6 or
#4 wires (depending on the amperage I choose) to the main lugs on the
sub-panel? If I buy a main breaker panel, is it just the lower of the
two breaker amperages from the main or sub panel that determines the
rating of the sub-panel, or is that a no-no?

If I choose to just run 6 new circuits back to the main panel and
dispense with the sub altogether, can I run all 6 through one hole in
the studs, or would there be interference or some other bad result?
Do I need to drill multiple holes in the studs to make the run back to
the main panel?

Thanks

What you propose to do is perfectly acceptable practice. The larger
main breaker in the feeder supplied panel becomes a disconnect just as
if you had installed an enclosed switch that some manufactures offer in
a breaker style housing for use in isolating feeders from back feeds or
complying with double block and break safety requirements in some safe
work practices policies. You do have to do a calculation of the load to
be served to be sure that the over current protective device and the
feeder conductors are large enough to carry the calculated load. It is
perfectly acceptable to terminate the feeder conductors on the main lugs
of a main lug only (MLO) panel. The rating of the panel is determined
by it's listing and labeling. Using the panel at any amperage at or
below its listing is fine.

If you run all six cables through the same hole then you will exceed the
de-rated amperage of the cables conductors. Shooting from the hip I
believe you can get by with three two wire cables in the same hole. I
would just buy the four conductor plus ground two circuit cable to make
pulling easier and run each two circuit cable in it's own hole.
--
Tom Horne,

"This alternating current stuff is just a fad it is much too dangerous
for general use." Thomas Alva Edison