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You're kidding about having electrical experience, right? After reading your post, I recommend you call an electrician.
Edited 9/30/2002 11:33:13 PM ET by allaround
You are kidding about your response right? Its not rocket science, its just about getting the right information. You dont personally know me, so please dont assume what my experience level is. Anyone have any real information?
Edited 10/1/2002 10:56:27 AM ET by drptop70ss
I'll try to provide a start without passing judgement...
First, there's some issues with your plans:
1. if you're putting 200A in the barn, what is your current service drop to the house sized for?? Add your house's service to the 200A, and that's what size drop you need to the meter box. So, if your house is 100A, your barn 200A, your drop into the main meter box needs to be size for 300A. I can't recall off the top of my head the wire size needed for this (250MCM Cu, I believe). Also... is your current meter box big enough to handle the physical size of these conductors? (Not only to allow space to route the wire, but lug size). A 300A meter box isn't your average sized meter box...
2. Probably more importantly, you need a means of safety disconnect at the meter or inside the house, to feed the barn. So, you now need a meter box sized for 300A conductors, but also a 200A main disconnect for the barn, at or close to the meter. (Otherwise, one wrong dig with the backhoe, and you've got a ton of fault current flowing... until that 200A cable acts as a fuse or you knock out the power to your neighborhood...)
3. Once you get passed that....
To make the run from your house meter to the barn, you'd need at least 2/0 Cu or 4/0 Al cable to support 200A. This cable size does not take into account voltage drop for whatever distance you need to travel. I don't have by code book with me to do the calcs...
Using type USE would be the easiest route since it's meant for direct burial (SE and SEU are not for direct burial!). I'd go that route instead of conduit (except for under the porch...) However, you'd need to check the code for burial requirements. 2' will most likely be required, unless you meet the other stipulations that would allow a trench not as deep. Oh, if in conduit the whole run you don't need 2' depth. Again, refer to NEC...
4. No phone lines/CATV lines with electric lines in conduit. Must be separate!
5. Don't forget GEC requirements. My area, you'd need to have your two hot, neutral, as well as GEC pulled between the disconnect and the panel in the barn, then the panel in the barn needs to be tied to two ground rods at the barn (6' or more apart). GEC for 200A = #4 CU...
6. Conduit above ground... Well... Make it sch 80 PVC or rigid, and make sure it won't get hit by anything... Even then, refer to inspector's demands...
Get yourself some good books (Code Check for Electrical definitely helps as an overview)... and do get an inspection done...
If you have as much aptitude for electrical work as you have for concrete, you're probably gonna end up dead at some point during this installation. Let me be the first to jump on allaround's bandwagon and urge you to hire an electrician.
You're right in the fact that it's not rocket science, but it's not DIY work either. You got a wife? Kids? Lots of life insurance? You're even more clearly over your head here that you were in the concrete slab posts, where the worst that could have happened is the concrete sets up around your feet and someone has to hammer you out. Electrical mistakes make dead men.
I guess the only positive thing I can say is if you end up dead, no one here will know which person's advice helped kill you!
We're just trying to protect you from yourself.
Eric
Hi Dave, My advise to you is to call in a qualified electrician. The reason I say this is you are putting electrical to a barn - therefor I assume you are on a farm or acreage. The first thing that comes to mind is, Do you have enough power comming from the power pole to service your 100 amp house and 200 amp barn? Although this sounds silly, where I grew up it was a problem. Transformers needed to be changed and overhead wire needed to be updated. The wire from the power pole to your house may also have to be updated to carry the new load. Why do you think you need 200 amps? What if you install a 200 amp service just to find out you need 300 or 400 amps? The electrician can help with all these potential problems.
I am not an electrician, but I do not beleive that the electrical code would allow you to run from the existing power meter to the barn. The reason I say this is your house is currently hooked to it. I beleive the perferred way would be to run from your house pannel to a sub-panel in the barn....which would be a problem as you have 100 amp service in your house.
Do the right thing, call in an electrician. Try to save money somewhere else.
Peter
Ah forget it, removed my post with the rest of the info. Thanks to all who had given me information in the past, I appreciate it, and thank you Burpinboy for the response, very good info. This site is full of good info but it always seems any time a question is asked you have to deal with a bunch of certain guys who just take away the fun of the whole thing. Some of you are very helpful and some just need to get over themselves. I wont bother with anymore questions, so have fun making fun of the HD shoppers and guys with vinyl siding :)
Dave
Edited 10/1/2002 6:06:48 PM ET by drptop70ss
Edited 10/1/2002 6:15:23 PM ET by drptop70ss
"This site is full of good info but it always seems any time a question is asked you have to deal with a bunch of certain guys who just take away the fun of the whole thing."
The fun of the whole thing? Fun? Electrical wiring? At one level, it might be fun, but it's dangerous, too.
electrical is not hard. A DIYer can do it easy. Only thing you need to know is do it exactly like code says, no other way. But the easy way is get the Taunton book " wiring a house" yellow and white cover by a guy name Cauldwell
electrical is not hard. A DIYer can do it easy. Only thing you need to know is do it exactly like code says, no other way.
Well, can you think of the reason I see screwed up electrical work every day? It's that "exactly like the code says" that sems to get them - a lot of folks don't even seenm to realize there is a code or any sort of rules.
Many of them can't even get the polarity right.
I got some like replys to a post I put up here. Just let it go. Do consider their advice on the pro however. My wife is down one cousin because of a bad electrical installation. He actually _was_ a licensed electrician and got killed doing work in the basement of some folks for whom he was wiring an addition. This was a trained, educated, and qualified union electrician. He died because someone had 'jack legged' the wiring before and he had a 'hidden' hot from what I understand. He's dead. Don't join him. He left two sons and a wife. His oldest graduates highschool this year. He never even got to go to any of his little league games.
I do electrical work myself, but I know where my limits happen to fall. (install outlets, run service to new outlets, new lights etc) At the least, try get a qualified electrician to come out and review what you are planning to install. It may just be the best insurance you ever buy. You may not find one that will do a consult on it. In that case, hire the sub-panel only. You don't have to hire the whole job, but at least get a code std service installed.
My electrician is willing to come by at the beginning or end of the day and chat with me at $52/hr. The initial consult took an hour and a half, and I wasn't charged for it, but they did charge $2400 for additional work, so I guess it was a profitable sales call. I see nothing wrong in getting a few bids on either part or all of the job. In the end, you might find that they suggest 100A service and an installation that is cheaper than what you were planning to do. remember, they have been at it awhile and have seen everything.
> someone had 'jack legged' the wiring before and he had a 'hidden' hot
You find the damndest things in old wiring that's been messed with. A friend of mine bought a 101 year old house, and found that the shield of the coax for the TV was hot. The best thing for this is one of those proximity sensors. They're about the size of those "Sharpie" felt tip pens, maybe $15. When the tip gets within half an inch of a hot, even if the wire is insulated, it lights up.
-- J.S.
I call the proximity sensor "the bleep." I use it on everything I'm doing. It is interesting in knob and tube houses how it will register a cold wire as hot. Usually getting up on a chair and away from wires in the floor will provide enough shielding, but better a false positive than a false negative. Sears had the GB model bundled with a nice set of stipper-cutters on closeout for $4.47 I bought all they had and now my friends all have one as well, so they can continue to be my friends.