Extension cord over 100 ft

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Cold in Edina

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May 25, 2014
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I have a 30 amp service RV (2000 sunnybrook, 28 ft) running from a 50 amp post.  If I use a 50 amp extension cord or two, then a 50 to 30 convert or plug, then one more 30 amp extension cord ..I can get a better view of the lake, but will I start a forest fire?
The trailer is to be parked for good, and we use it seasonally, for at most a week at a time.  the cord will lay on the ground through a slightly wooded area and be stored in between visits. 
 

Ned

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The 50A cord will be fine as you won't be drawing more than 30A through it.  As long as the 30A cord is of suitable size, it should be OK too, especially in the open air.
 
B

bucks2

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50 amp extension cords are expensive. You may be better off long term, with a piece of conventional wiring with the appropriate plugs on the ends. A single long wire is better than one with multiple plugs. Depending on the ground, you might even be able to bury it reasonably easily and make it semi-permanent.

125 feet of 8-3 romex is $159 at Home Depot (http://www.homedepot.com/s/8-3+romex?NCNI-5) plus ends (one 50 one 30) will be close to $200.

25 foot 50 amp extension cord w/plugs is $99.99 on Amazon. Three of these plus a 50 foot 30 amp is over $370. Plus the cost of the dogbone, so roughly $400 or twice the cost.

Here's the math on wire size. http://www.paigewire.com/pumpWireCalc.aspx  (120v, 125 feet, 5% loss, 30 amps)

Ken

 

Ned

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Since the trailer will be permanently installed, Ken's suggestion of a buried 50A feeder is an excellent idea.  I would put a 50A outlet at the trailer even though you're only 30A now because who knows what will come in the future.  However, that would cost more and require larger wires.  I would run PVC conduit for the buried run, but that's my preference.
 

Cold in Edina

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This is great info, I can put the trailer where I want! I had seen some wiring size and power drop calculators, but was not sure how to use them.  Thanks.  Bury it for safety? Or ?  And if I build my own am I safe?  What do I look out for, or do I take it to an electrician?
 

Cold in Edina

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I googled installing the plug and I CAN DO THIS.
So, I get a great view of the lake.
I save money
AND I am empowered!!!!

And I am unlikely to burn down the forest.

Thank you so much. This is a great forum. 
 
B

bucks2

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Burying is a site specific thing. IF the digging is easy then it's the best way. If it's hard you'll be tempted to not bury deep enough. If you have a friend with a bobcat and hoe, its easier still. Remember to use direct bury wire if you go that way. Use conduit if you don't use direct bury.

If you lay it on the ground, which is an easy way, be very careful if you need to mow grass, drive across, etc. Take good care of the wire and it'll take care of you.

I would be careful to use only the size plug on the trailer end that the wire is sized for. That is, if you use the 30 amp wire, only put a 30 amp female plug on that end. You'll be fine with a 50 amp plug on the male end of the wire because that extra terminal will be left unconnected, you'll only use a hot-neutral-ground wiring arrangement.

This ain't rocket surgery. But if you know a rocket surgeon it wouldn't hurt to get his help..........  ::)

Ken
 

HueyPilotVN

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Reading this post might help give you some insight to running your wire.

I am not saying anything about permits or local codes, just a little practical advice.

http://www.rvforum.net/SMF_forum/index.php?topic=66762.msg611714#msg611714

Good luck.
 

robertusa123

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100 feet is not far and you really don't need to worry about power loss.    I'd be more worryed about all the connections. That where the problems come from.    Either get a one piece 100 foot cord made up. Or have a hardwired outlet installed.  The worst part will be digging the trench
 

driftless shifter

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Rent a Ditch Witch, unless your land is real boney. Be aware that future digging may happen on your property. Make a map of your buried wire. Take triangulation measurements at every change of direction for the ditch. Use corners of the foundation to measure from, and note which corner is which. Post the map at the sewer clean out the water meter/wellpump and anywhere else underground utilities enter the basement. Not so much for you, you'll know where it is, but for the next owner and the guy he hires to put in irrigation, or a pool. It's a bad thing digging up electrical service you didn't know was there. Especially if its live. If you don't pull a permit and someone gets hurt ... I didn't pull a permit for a 220v 50amp panel in my shop. Permits are a pain in the not so liberal Commonwealth(another word for socialism) of MA., where you can't put a new roof on without 2 permits. One from the town gov't and one from the Hysterical..err.. Historical Commitee.

Bill
 

kjansen

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If you are Edina Mn and are in Minnesota, Drifter is on.  A ditch witch is the way to go.  It will only take an hour or so to dig.  I did the same thing and even tho I used under ground wire, I still put it in plastic conduit to help keep rodents from chewing on it.  By code dig the trench 18" deep, cover the wire with 12" of dirt and then put the red electrical plastic tape in the trench and fill in the remaining 6" of dirt. If some one starts digging they will hit the red tape first and then know that an electric wire is buried below it. 
 

Cold in Edina

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I think I will leave above ground and use a plug. Did I mention the power outlet is the neighbors? There is nothing built or installed on the property... No electric, no buildings, no sewage, no water....we haul tanks from nearby campgrounds.  I think using a plug and picking up each time we leave is the way to go.  We consider this a huge improvement over a generator. We will be situating it away from driveway and areas we use to avoid tripping or wear on wire. When we are there the dogs will keep the critters away, when we are gone we will pick it up and store it. Am I missing any problem with this? We are there maybe 6 or 7 weekends.  Again, thanks to all.
 
B

bucks2

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I think you're doing just fine with your planning. The rest of us all have different situations in mind and we like to cover all the bases. An above ground extension cord in the situation you described just now will work well.

ken
 

Ex-Calif

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Welcome aboard Bee but you are replying to an 8 year old message thread. No problem, we all do it occasionally.

He's either happily camping on his land or he burnt everything to the ground years ago - LOL...
 

Gary RV_Wizard

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I have seen several fires recently where they started when someone was using a 30 amp extension cord to connect to a 50 amp power source. The problem is that 30 amps is not enough to carry the load. The current will get so high that it will arc across and start a fire.
The size of the load (amps) is not determined by the amp capacity of the source, i.e. connecting a 30A load to a 50A source doesn't automatically overload either the cord or the device. Amps are pulled from the source by the load, not pushed by the source into the load. So yes you can overload a 30A cord by pulling excessive amps, but only if the load is greater than 30A.
 
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