On Mon, 26 Jan 2004 09:04:52 -0600, Peter De Smidt wrote:

I'm trying to turn my 1-car, 70 year old garage into a workshop. At the
moment, it has two 15 amp lines run through 1/2 metal conduit. The wire is
14 ga, and there are two hots, one neutral and a ground. I'd like to
increase this a bit. I was thinking of putting in a sub-panel. I'd like
to be able to run the new wires in the same conduit, as it's a little too
frozen here at the moment for me to dig a new trench. My idea was to
replace the 14 ga wires with 10 ga. According to my sources, a 1/2 metal
conduit will take 5 - 10 ga wires, and so 4 should be no problem. My
understanding was that if the run was under 35 ft, that each of the 10 ga.
hot wires would support 30 amps, and hence that I should hook each hot
wire to a 30 amp breaker in the main box. The salesman in the Menards
electrical section told me that this wasn't right. The four wire system
would only support 30 amps. Any comments?

-Peter De Smidt

The fact you are posting here would seem to indicate that you are unsure
of wiring and buiding codes. Your best and safest bet is to contact your
local building or electrical inspector to ask for their recommendations.
Other than having to pull a permit, the advice should cost you nothing.
In our community, a homeowner can do his/her own wiring as long as it is
done up to code.

Another choice is to pay an electrician as a consultant with the
understanding you will do the grunt work.

Trusting the advice given in newsgroups is always iffy. There is much
good advice here but how do you know which is good and which is not?

Bad wiring can cause fire as well as physical harm. Unless you are
absolutely sure and comfortable with wiring and electricity, seek the
right advice. 'Tis but a very small price to pay for contentment.