Despite the markings, still be careful when digging. Today at work a contractor broke a gas main - the markings were about 6-8 feet off!
In this case the owner doesn't get charged a cost recovery fee/repair fee from the gas company or Fire Department. If you cut the line and it was where it was supposed to be - you'll probably get charged. FYI.
OK, so I've got all my stuff together, got the trench ready, etc. Got a basic question for somebody in the know.
The run for this thing is right at 90 feet. It'll be a 30 amp single pole breaker in the panel inside the house, run thru conduit all the way to the pedistal next to the Airstream. SO, will the #10 TNNH be big enough to handle the full load without a lot of line drop? Seems a little long, but I'm pretty sure I've got runs at least that long inside the house for the 15 amp circuits to wall outlets and so on.
Jim
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To lodge all power in one party and to leave it there is to insure bad government. -- Mark Twain
Any chance the sewer line could break as well? While you have the big digger, it sure would be nice to put in a private dump station.
That is a VERY good point ! Think about it, you have guest over or you don't go anywhere for a while, you don't have to have that thought in the back of your head about what's going on in the "black tank".
Rick
__________________ "Better to have more then you need, then need more then you have because you don't have enough!" AIR #: 8129
Rats. I was affraid of that. The largest wire that the camper enclosure end is supposed to accept is #8. Will it hurt to trim it down at the connection points to about a # 8 size, or will that cause over heating under a full load?
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To lodge all power in one party and to leave it there is to insure bad government. -- Mark Twain
Let's not forget the wire cord length from the trailer to the outlet counts also. So oversize the underground run or get a short as possible cord to hook up. You'll also want an additional outlet out there for working. I'll also suggest you consider cable made for burial and wet locations. It will most likly be wet inside your conduit. Besides if you aren't using steal conduit you aren't really adding much in the way of protection.
I await to be corrected by the professionals.
Not enough information - but a strand or two short of a full bundle will not act as a fuse point unless things elsewhere are fubar and hot wire then would be a moot point. 8AWG comes in at 2.91% drop for your 90 feet but I would sure recommend the step up to 6AWG (1.81% drop) if you can swing it just to better handle surge currents when the whole grid is stressed on a hot day, etc..
Using a six-inch chunk of 8AWG to terminate into the fixture with an excellent crimped connection onto the 6AWG may not be elegant and may even be frowned on by the powers-that-be but the chances of having a terminal shatter a year later would cinch it for me.
With 8awg = 3.26mm & 6awg = 4.12mm that is a big jump in the stiffness of the conductor so perhaps the limit is strength of its construction dealing with exuberant electricians pushing excess wire in to get the cover closed.
Rats. I was affraid of that. The largest wire that the camper enclosure end is supposed to accept is #8. Will it hurt to trim it down at the connection points to about a # 8 size, or will that cause over heating under a full load?
my opinion:
don't trim the wire, do it right, you'll be ahead in the long run. extra power is better than less power. you'll smile every time you use it instead of wondering if it's going to go south.
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Ricky
give life. kidney & pancreas transplant 9/9/06
Ingrid - my unofficial '"World's Oldest Airstreamer"
January 1909 - October 2008 R.I.P.
1) Don’t screw around with a possible fire, or worse. Go with #6. I had about 100 feet lying around that a buddy gave when we wired his new wood shop back in June. I made another trip to Lowes and bought an additional 100 feet for the second run (hot, plus neutral). Another buddy is going to give me 100 feet of #12 for the ground back to the panel in the house.
2) I have about 20 feet of bare #10 that I got from who knows where, once upon a time. That will be tied to the ground lug inside the box next to the Airstream and will be buried in the trench going the opposite direction to the main line going into the house (I intentionally made the trench about 10 feet longer than it needed to be).
3) The largest wire that the weatherproof box that I bought to go next to the Airstream (outside, on the pedestal) is #8 (had to take a second look to be sure). I have some #6 lugs that will fit the screws on the outlet perfectly. So, I’ll crimp those babies on the wire and tie ‘em down.
Now, if I just had an entire day without interruptions to complete the dang thing. I hate pagers.
Does anybody see any chinks in my plan? Thanks to everybody for your help!
__________________
To lodge all power in one party and to leave it there is to insure bad government. -- Mark Twain
Sounds like the project is moving right along, such a neat idea too. I can tell you I have pondered putting in a hookup out at my moms more than once, its good to watch how you are doing it. Keep us posted.
Just a quick update to say “thanks” for all the tips and suggestions and let everybody know that I finally finished this project last weekend.
I wound up using 1” conduit to run this to the main distribution panel inside the house. That made pulling the wire much easier. I carefully re-measured the run length and it turns out I could have used #10 wire, but it was right on the edge of #6 or #10. Since I already had some #6 on hand, and because it’s always best to err on the side of caution with electricity, I used the #6. Also, I was able to speak to a licensed electrician just before I hooked all this up, I decided not to run an additional ground into the trench. He said that if I did that, I risked the new ground becoming the main ground (that is, the actual earth ground) for the entire house. In other words, make this a regular circuit out of the panel, don’t make it look like a new extension from the same (like a detached garage, for example).
I loaded the circuit up with about 25 amps inside the camper on Sunday night and had good results with the new circuit. The wire remained cool to the touch end to end (pedestal next to Airstream to the panel in the house). (I don’t recommend that you reach in a grab these wires, btw, unless you’re used to dealing with these sorts of things.) The one issue that did crop up was that the wire from the Airstream to the pedestal got a bit warm (not hot) only at the connection point to the pedestal. This wire has apparently gotten overheated in the past, so now I have to consider replacing it. Dang, more money to spend.
Speaking of money, this entire project cost about $150 direct out of pocket. I had the advantage of having about 2/3 of the wire needed already on hand, and the trencher expense is not figured into that number because I had to rent one anyway to replace the water main for the house.
Anyway, thanks for the tips everybody! Hope maybe this helps somebody down the road. One piece of advice that I can’t stress enough, if you’re going to try this on your own, it’s really not all that difficult. BUT, consult a licensed electrician or engineer first, take your time and overbuild the circuit. Safety is first priority.
Jim
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To lodge all power in one party and to leave it there is to insure bad government. -- Mark Twain