Yesterday I had a question, and the only answer I got I couldn't understand what the gentleman meant. Of course, I don't know much, if any, about electricity, and I need to buy the supplies for a friend to install it... I'm bringing power to my workshop in my backyard, about 90 feet or so from the main panel. I plan to have two circuits that will operate a cooler, and the other one any of the power tools I have in the shop. The most powerful of such tool is only 18 amps, and any tool will be operated one at the time... My friens said to hook a 30 amp with two hot wires (#10) on the main box, and bring such a wire to the subpanel in the workshop... There, we can have two 20 amp circuits, using #12 wire... The question is... Is that right?. Would anyone have other ideas?. Thanks a lot for any suggestions.

What he was saying was to use #6 wire, if you can afford it, not #12. While #6 may be a bit large, but #12 is definitely too small for a loaded 20 amp circuit running 90 feet. Esp if a motor tries to start. #12 will produce 6.9 volts dropped, more than the recommended 5%.

I will suggest #10-3 UF cable, direct bury it in a 24" deep trench. Or use #10 THWN in 1" PVC conduit, then the trench can be 18" deep.

Be sure to use 4 wires, 2 hots, black and red work, 1 white neutral, and 1 green equipment ground.
I do like the #6 suggestion thou, it will offer future expansion, and never have voltage dropped problems.

To Tkrussell... Thanks a lot!. Your answer was very clear!!