I have a pole barn about 180 feet from my breaker box in my house. I want to run electric to the barn to run a compressor and misc. tools, maybe a small welder. I need to run it from the house because it will be much more expensive to have another line run from the pole, new meeter, etc. I get a VERY good price break 8 months of the year for having an all electric home. If I put a new meeter on the barn, I would have to pay a much higher rate and at least $15 a month in admin charges.
That said, I have a Wadsworth breaker box in the house which has one open slot. I am looking for someplace to steal one more slot so I can put in a double pole 60AMP breaker. That will be my supply for the barn.
Now the questions [img]/forums/images/icons/wink.gif[/img]
Question 1: In the barn, do I need a "main lug" or a "main breaker" breaker box. My understanding is that the "main lug" box doesn't have a main breaker in it and would rely on the 60AMP breaker in the house to act as the main for the barn. I'm thinking I would want a main breaker in the barn, maybe for code compliance, but also for when the breaker does pop, I can reset it right there without a trip to the house [img]/forums/images/icons/wink.gif[/img] I just don't remember seeing a 60A main breaker box the last time I was at the box stores, I'll look again.
Question 2: After some research, I was thinking the wire size should be 4AWG copper to reduce voltage drop to a minimum and to carry the 50 amps. Does this sound right? Also, if that's the right size, what do I look for exactly, is it 3 or 4 seperate wires, all in one, etc? Is copper the best choice for this?
Question 3: Do I need to run it in any kind of conduit? Or just bury it? How deep?
Thanks for any help!!! I have been trying to figure this out from reading other stuff on and off line. Just when I think I know what I need, I find something else that makes me second guess myself. [img]/forums/images/icons/confused.gif[/img]
There are a lot of people on this board who are a lot more qualified to answer your questions that I am.
However, until they answer your questions, I will give it my best shot.
You should have a main breaker box in the pole barn.
You mention 60 amp and 50 amp, which is it? If you are going for a 50 amp #4 would be the correct size. If it is going to be 60 amp you would need #3. This would be for 240 volt. You would need four wire copper.
To bury the wire, it would have to be the type suitable for ground burial. Conduit would not be required.
The burial depth would have to be a minimum of 18 inches.
Your local code may vary so this should be checked for compliance.
Had the exact situation myself. Pole is on South side of house, about 30 feet from south-facing wall. Cable enters house underground into crawlspace and up to load center which is fairly centrally located in the house. The pole has a 200 amp main breaker on the meter panel. House has 200 amp breaker on the load center. Wire from pole to load center, as I recall is 1/0 aluminum.
I spliced at the connection in my house panel using grundy clamps and connecting just below the set screws for the load center bus bars. I ran the wire back down from the panel, through the crawlspace to the North side of the house toward my workshop. I used 2/2/4 aluminum wire which is rated for outdoor use, but in my case, I trenched to 18" and ran the wire in 1" PVC conduit.
In the workshop, I used a 100 amp load center, obviously with a 100 amp main breaker. I never did check the ampacity tables on the 2/2/4 aluminum to see if it had a 100 amp rating, but rather took the building supply vendor's word for it. I run a rather large single phase 220v welder (rated at up to 72 amps input current at rated max power). I'll never use that much current, but my outfit is wired safely and functionally. We don't have code in this county, so safe and functional works for me. Some places have strange requirements on ground wires, sub panels, and such when feeding detached buildings.
If code is an issue with you OR if you don't fully understand what you're doing, make sure you get help from a qualified electrician. It'd be a bummer if you burnt the place down.
Thanks Dave! I meant to say 60A breaker. I found one online yesterday and ordered it. Wadsworth breakers are somewhat hard to find at local stores.
So #3 copper it is, but I'm still confused as to what to ask for. Will it be one cable with 4 connectors, or will it be for seperate wires?
Also, do you know if the #3 wire will fit into the 60A breaker? I remember looking at a couple of breakers the other day and I don't remember them having a BIG connector...
Thanks again for the help. I'll definately check the local codes to be sure, good point.
Thanks Dave (other Dave) [img]/forums/images/icons/smile.gif[/img]
I'm kind of curious... if I understand you right, you connected the feed for your subpanel directly to the bus in the main panel, without a breaker? [img]/forums/images/icons/confused.gif[/img] I didn't know that was an option, also not sure what a grundy clamp is? Any pointers for more info on these?
So, does it connect before or after the main breaker? If this is an option for my project, it might actually work better for me, especially since I am going to have to work hard at finding another open slot... I'll have to dig into this a little more.
A couple of months ago I had a similar situation: I had to power my new barn 850 feet from my meter. After some discussions with helpful people at ID Electric, a local electric supply store, I decided to rent a trencher and burry a #2 (Stevens) aluminum wire in the trench. No conduit. The cable connects a 60 AMP breaker at the pole and a panel with 3 20 AMP breakers (for now) at the barn. Works like a champ.
What you will need is a cable that comes with four wires in it. One should be black, one red, one white and the ground. As far as fitting the breaker I could not tell you if it will or not.
I haven't seen too many breakers that fit into a residential 200 amp box that could handle #3 wire. Make sure the breaker you have purchased can handle #3.
If I needed 60amps I would install another box off the main feed that was more like a junction box with a large main type breaker...
As I said I just did it. I used 3 wires, one black (live 1), red (live 2) and green striped smaller wire (ground), this will give you 220V. You can tape 110V or 220V from it.
I bought 60A breaker for 220V (dual switch) at HD, fitted nicely into the main 200A panel and connected the big 2AWG live wires with no problem even though the 2AWG aluminum wire is about the thickest you can get.
[img]/forums/images/icons/tongue.gif[/img] I'm going to step in and tell you what Inspector 507 would probably say if he posted to this thread. [img]/forums/images/icons/tongue.gif[/img] THE PROBLEM here is that the house panel is NOT A DISTRIBUTION PANEL. That is to say that the lugs that are available to plug a breaker into were never intended to take that kind of load off the bus in one whack. The household-grade panels like to have three 20-AMP breakers hooked to three lugs rather than one 60 AMP breaker hooked to one lug (one lug per leg). [img]/forums/images/icons/tongue.gif[/img] I just could not tell you how many "hot spots" my Infrared Camera has revealed; hot spots that were caused by "bootlegging" a heavily-loaded branch circuit off of what was basically a residential-grade panel. [img]/forums/images/icons/frown.gif[/img] If you can figure out a way of taking current off that panel by attaching to the main bus and then going to a 60 AMP disconnect, you'll be beter off. [img]/forums/images/icons/smile.gif[/img] I just cannot for the life of me remember what a Wadsworth breaker has for a bus connection. Some styles of bus connections will let you get away with murder, and some will just burn down at the least amount of abuse. If your breakers are held on by a screw, that would be very good, and it's the only way you would be able to get by with taking a large feed like that off that panel. [img]/forums/images/icons/tongue.gif[/img] LUCKILY, shops don't normally have a high sustained load; it's just those pesky air compressors that seem to do such a good job of burning down marginal power supply systems. [img]/forums/images/icons/crazy.gif[/img]
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