# Feeder to detached barn, Cable selection



## kgroesch (Aug 24, 2008)

I have a small house in the country with a metal barn about 50 ft. away.  I want to run a feeder from the main panel of the house to the barn.  I plan to do the following:

1.  Come off a spare 30 Amp 220V break that was orginally for a water well pump we ended up not needing.
2.  Run feeder through PVC, 18" underground with the warning ribbon 12" above the conduit.
3.  Install a subpanel on the back of the barn. 
4.  Install a new ground rod at the new subpanel at the barn.
5.  The subpanel will have two 20 Amp breaks for 110V circuits for now.

My question is, can I run a 10/2 cable for the feeder or does it have to be a 10/3 cable?  My understanding is that a ground wire is not to be used between the two structures which is why I will install a new ground rod at the new subpanel.  Just wasn't sure if I can use the bare copper conductor in the 10/2 as the neutral for the 220V circuit.


----------



## triple D (Aug 26, 2008)

You must run a 10-3 w/grnd. It also must be rated for use in wet conditions, even though it is in a conduit. So romex style is not an option. Thhn will work if you dont want to spend on uf wire. The ground is required between all equipment and panels. Depending on your area, one rod may work, some require two 8ft apart. Keep your neutral wires on floating bar, not attached with grn. screw to panel. Put all grnds on a grnd bar attached to panel box. Other than that the only thing I can think of is 24" deep, unless your under concrete. Good luck, hope I am of help to you.....


----------



## kgroesch (Aug 26, 2008)

Thanks for the reply.  It all sounds reasonable except I had a question on the 24" deep statement.  Is this just your preference for added safety or am I misreading the code?  Table 300.5 in the NEC 2008 code states 18" for Nonmetallic Raceways Listed for Direct Burial Without Concrete Encasement or Other Approved Raceways.  It states 24" for direct burial of cables without conduit.


----------



## triple D (Aug 27, 2008)

People dig for me, I just tell them 24". That way I'm safe either way. Way to be handy with the code my friend, good luck....


----------

