I have a shed which is a little less than 100 feet from my home breaker box. I currently am poor-manning it running a 100 foot extension cord out there. I have already purchased a branch electrical box and wired the shed. I am about to rent a trencher to trench for the electrical cable.
I would like to run 240v out there just in case I ever need it so I do not have to redo the job in the future. However, at this point I want 2x 20 amp circuits running out there for saws and things on one breaker & lights, tv, receiver etc on the other. I am going 20 amp vs 15 amp just to have some extra capability. If your opinion on this differs, I would like to know more.
So here is my main question. With a 3% voltage drop in mind, what wire do I need to run out there given the distance (100 ft) to obtain a max 20 amp 240v capability and/or 2x 20 amp 120v capability? Can I go with a smaller gauge electrical wire to achieve this or is 6/3 what I need to go with? I do realize that the most important part of the equation are the breakers installed on the home side. Those must be at or below whatever electrical cable I run out there. Would it be possible to run 1x 10AWG/3 UF-B electrical cable out there with 2x 20 amp breakers in the house?
The online electrical wire calculators are confusing me... I guess what I do not get on the 3 conductor cable is if the cable is capable of supporting 20 amp per hot wire or a total of 20 amp across all 3 conductors.
Is it reasonable to assume that a 100 foot 10AWG/3 Conductor wire is capable of carrying 2x 15 amp loads @ 120v or 1x 30 amp load @ 240v?
I do not plan on welding (due to wood shed/wood shed floor) or anything like that. I can also probably step down to two 120v 15 amp circuits as I can only operate a tool at once. i may want to install an a/c unit out there though at some point. probably 120v. the shed size is 12x20.
This install location is in east north Dallas. Lots of clay and rocks. If i can avoid digging an 18" ditch, I would definitely prefer it. I will not permit the install but do want to follow code and do so with the cheapest trenching method and electrical cable possible.