240v wire to barn size?

[dieselcrawler]

At 200' +/-, voltage drop calculations come into play. The 100a mobile home cable you ordered should be adequate at the distance and derated to the smaller breaker you plan to use. Be sure to bury it 18"+ deep, and put 'Caution Buried Electric' red warning tape over the buried line, about 6" below the surface.

As you may know, resist the urge to drop a water line in the same ditch, or phone line. Both should be seperated by 16"+ from the electric lines. Phone line for signal interference reasons, water for the obvious reason that water and electric dont mix well! But you can get away with one 18" wide ditch, with electric on one side, and water and phone on the other...

 

[Fuddy1952]

Today we decided to put the panel box just inside the door I'll be using. That will be less than the 200', about 130 ft. from garage box, so even less v-drop.
Maybe I should go with a larger breaker (60-70 amp?). Then another main in horse barn box, then three 20 amp ones should be enough.
As big as 2 gauge is, can I fit wire into breaker?

 

[3Ts]

With that aluminum wire be sure you use an anti-oxidant (such as Noalox or Ox-guard) on all the connections.

And I vote for the use of conduit - even if you use direct burial cable.

And I also vote for running it as a 240v out to the shop and splitting it there. You'll need 240v @ 50a for all the welders I know of. (Note: I've run some 50a welders on 30a circuits, but you have to be careful of loads) and plan for future expansion - it's much cheaper now than later.

 

[SJay]

If you want internet access add a cat 6 cable. I have a separate modem in my pole barn just for Pandora Radio. Very nice to have a hard line to your barn. Just a though.

 

[PILOON]

# 8 copper or #6 alu should handle most of what you'll want.
Perhaps even #10 copper will suffice (8 4 alu)
4 strand. red black white and neutral is the way to go.
Conduit is good advice as probably cheaper than direct bury cable but go bigger than the wire as in future you can also insert more leads. (plastic conduit is cheap).
Conduit can be as simple as black PVC piping, eg 2" black PVC.
Just be sure the ends are above ground so as no water may enter.
If PVC (or) also add a pull cord for any future use. (who knows, computer cables, audio etc)

 

[Fallon]

Go bigger on the amperage (and appropriate wire gauge). than you think you could need. Double is good. Put it in conduit & dump in extra conduit. Conduit is cheap, wire less so, but digging trenches is expensive. Overkill wiring & extra conduit means never having to dig it again (an next time avoid the first wires & conduit.

It's also easy to but a small main breaker or more branch breakers in a big box. I got a free 30? Slot breaker box for a couple bucks full of breakers from somebody remodeling. Love having all those spare slots for every new project out in the barn. No spare room on the house panel, which is an issue for some extra circuits I want to install.

 

[JeffInCO]

I ran about 150 feet of 2-2-2-4 direct bury last summer. A few tips -- especially if you're having it inspected:

1) The National Electric Code requires direct-bury wire to be down 24 inches. Wire in conduit is allowed to be 18 inches.

2) For any portion that is exposed above-ground (and I think below the surface down to the bury depth of 24 inches), code requires that the cable be in conduit. If that conduit is PVC, any portion of the conduit that is "exposed to physical damage" is supposed to be SCH80. My understanding is that some inspectors consider any above ground conduit to be "exposed to physical damage". Others do not. I used SCH80 for the above ground portion to avoid any argument with the inspector on this topic.

3) I would not put the whole run in conduit. If the whole thing is in conduit, the code limits you to 360 degrees of bends along the entire run, and you can't use any old pipe that you have laying around (it needs to be listed for the intended use). Trust me -- you don't want to pull 120 feet of 2-2-2-4 aluminum through 360 degrees of bends anyway. It's very stiff cable!

4) For any portion that is in PVC conduit (including the part above ground at each end of the run), in order to not exceed NEC conduit fill limits, your 2-2-2-4 needs to be in 1-1/4" or larger PVC.

I'm not an electrician, but having done a similar project myself (with a permit and inspections), I had to take the above into consideration. There are certainly other requirements in addition to the above, so please don't take my list as comprehensive.

Good luck!

Jeff

 

[Tractor Seabee]

Whatever you do put it in conduit, if you live long enough you will be glad you did whenever you have trouble if not your boys or whoever comes along behind you will appreciate it.

Service entrance cable is a bear to pull through conduit; actually all aluminum cable is harder to pull (see the fill charts). Eliminate bends with use of handholes. Always go over on conduit size, some years later you may want to increase the ampacity.

Ron

 

[Tractor Seabee]

With that aluminum wire be sure you use an anti-oxidant (such as Noalox or Ox-guard) on all the connections.

And I vote for the use of conduit - even if you use direct burial cable.

And I also vote for running it as a 240v out to the shop and splitting it there. You'll need 240v @ 50a for all the welders I know of. (Note: I've run some 50a welders on 30a circuits, but you have to be careful of loads) and plan for future expansion - it's much cheaper now than later.

Check the code; I believe you have to down rate the cable due to heat dissipation. If you are using conduit it is a waste of $ to use cable also. Use THHN/TWHN single conductors. Buy all white and color the ends black, red, white, and green. Buying rolls is a lot cheaper than cut colored lengths.


Ron

 

[3Ts]

Check the code; I believe you have to down rate the cable due to heat dissipation. If you are using conduit it is a waste of $ to use cable also. Use THHN/TWHN single conductors. Buy all white and color the ends black, red, white, and green. Buying rolls is a lot cheaper than cut colored lengths.

This is true. I suppose I should have mentioned derating, it's required for any more than 3 conductors in a conduit length of more than 2 feet. And individual wires (like THHN/TWHN) are expected. Typically romex or SE (service entrance) cable is not put in conduit due to heating issues. And don't bundle all the romex together when running thru the walls, they need to dissipate heat also.

Also, larger conduit makes it easier to pull cables. But, unless you really really have to, don't go bigger than 2-1/2" on conduit, the residential boxes do not accomodate more than 2-1/2" and adapters are really expensive for the larger sizes.

Typically, I try to do no more than 1/2 full on the conduit fill charts.