> I'm running some electrical cable from one buildeing to another and I
> need to go underground for about 30 feet. I'm going to run 3 lines of
> 12/2, unless there's something better, but I'm not sure how best to
> run it. I laied some conduit for some Cat5 cables that I needed to
> span the same section, because I figured I might be adding additional
> lines in the future and wanted easy access. I don't think I'll have
> the same requirements for the electrical, and I've heard that I don't
> want to run the electrical in with the Cat5 becuase of interference.
I've already purchsed the UF cable, didn't notice it at the time I
> bought it, but I've got it now. So, my question is, should I direct
> bury the cable or run it through some conduit. I don't have money to
> burn, but I want to do this correctly. Just for reference, I live in
> rural central Illinois, if that makes any difference.
> Nate Baxley
If you want a job that complies with the US NEC you can not run multiple
branch circuits to an outbuilding. In other words your electric supply
should be in a single branch circuit or feeder unless you run emergency
power, or you have two or more types of power with different voltage
characteristics which is very rare in homes.
The code requires that each building be supplied by only one feeder or
branch circuit and that there be a disconnecting means for each
building. If you run only one branch circuit the disconnecting means
can take the form of a snap (toggle) switch or set of snap switches.
The set of snap switches is three or four way switching rather than
multiple single pole switches on separate branch circuits. If your
loads can be served by two circuits then you can run a multiwire branch
circuit and use a double pole snap switch as the disconnecting means.
If you have a separate emergency power panel then you can run a third
circuit from that to get the three you want.
If you do install more than one branch circuit you need to build a
grounding electrode system for the outbuilding. That system will
consist of a minimum of two driven rods if there are no other grounding
electrodes such as a concrete encased electrode. The Grounding
Electrode System will have to be connected to the Equipment Grounding
Conductor (EGC) that is run with the circuits supplying the outbuilding.
If you want to allow for future change of use and loads then you will
run an 1&1/2" nonmetallic conduit between the house and the garage.
Install a six slot sub panel; minimum; in the garage, Install a back
fed double pole breaker that is fitted with a tie down kit in the garage
panel to use as the required building disconnecting means. Install a
separate Equipment Grounding buss bar in that panel. Remove the bonding
screw or strap that connects the insulated neutral buss to the garage
panel's cabinet. Run the Grounding Electrode Conductor from the
grounding electrode system of the garage to the equipment grounding buss
of the garage panel. You now have breaker slots to supply your three
branch circuits and you still have one open slot for a future 120 volt
load. If you want to allow for 240 volt loads then you will want to
install an eight or more slot panel so you will have more spare slots.
The supply to your garage sub panel will take the form of a three wire
plus ground feeder that you will size to carry your present loads and
leave some ampacity for additional loads.
I hope this answers your question. If you need more information just ask.