"zxcvbob" wrote in message
...
rchtravel wrote:
I have a barn that needs power and requires a wire run of about 75-80
feet (actual run length from box to box, not just the distance from
house to barn). What I would like to do is run direct bury, #2
aluminum (4 wire) from a 100 amp breaker in the house sub-panel,
underground to another 100 amp sub-panel in the barn. The electrician
I hired 2 years ago said that doing so would not be a problem as long
as the 2nd sub panel in the barn was properly grounded. I would like
other opinions or advice on this please.

Why 100 amp instead of 60 amp in the barn you ask? Why not, besides I
already have a Square D 100 amp panel I bought that was much cheaper
than 60 amp panels I looked at, not to mention the expandability 100
amps offers. In the barn I plan to run lights, 20 amp power outlets,
an air compressor (220), small arch welder (220), gas furnace, and
typical power tools such as a table saw, drill press, etc...

Of course, if my "plans" aren't safe, than I would certainly change
whatever was needed to be considered safe. That's why I'm asking for
feedback from this group. In hind-sight, I really wish I would have
bought a new 200 amp panel when I remodeled the house. Ah...if only I
knew everything....lol


Run the 100A subpanel feeder off a 60A or 70A breaker; it will be plenty
of
capacity for what you are doing, the breaker will be a lot cheaper, and
the
feeder conductors can be a lot smaller and cheaper.

-bob

I agree with this and would recommend taking it off the first panel or
whichever panel makes the wires long enough to reach either panel should you
upgrade one of them to 200A. Main reason being do you have any more neutral
lugs that can take a #2 wire? Do you have proper bending space for a #2
wire? Those big neutral lugs tend to disappear quickly. If you only have #4
holes, then a 60A feeder would be good with aluminum wire.

Its OK to feed a 100A panel with a 60A feeder.

--
Mark
Kent, WA