Extension cords

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BernieD

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I've always heard that the longer your extension cord run is the thicker should be the wire. I have a 25' 50 amp land line cord attached to the coach. I have 2 extension cords about 25-30' each. One a 50 amp, the other a 30 amp. I also have converter plugs that will let me go straight from 50 to 30 to 20 amp. Ok, so if all I need to use is one extension cord, should it be the 50 or it doesn't matter ???
 

BernieD

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Carl Lundquist said:
All other things being equal, use the heaviest cord you can to cut down on line losses.

Carl

That's why I asked, the 50 amp cord is the heaviest, weighing probably 3 times as much as the 30 amp cord :D
 

Karl

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Bernie,

HERE is a handy chart and calculator to determine voltage drop and percentages for different wire sizes. If using multiple extensions cords, remember to add the individual voltage drops together to get the total. As you can see, the percentage voltage drop for a given wire size is 10 times as much at 12V as it is for the same wire at 120 V; a big concern when running low voltage loads. Keep 'em short, keep 'em big. ;)
 

John From Detroit

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One thing to remember about 50 amp cord is that not only does it have more Copper in each wire so that it can carry more power

It has 4 wires as opposed to 3 in the 30 amp cord
 

Gary RV_Wizard

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If you are ultimately plugging to a 20A source, it doesn't matter. Any of those cables will easily carry 20A. If plugging to a 30A source, the 50A cable has a tiny advantage over the 30A, but significant only at the full 30A load.  If plugging to a 50A source, then the 50A cable is the oly choice, both for amps and 4 wire vs 3.
 

BernieD

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RV Roamer said:
If you are ultimately plugging to a 20A source, it doesn't matter. Any of those cables will easily carry 20A. If plugging to a 30A source, the 50A cable has a tiny advantage over the 30A, but significant only at the full 30A load.  If plugging to a 50A source, then the 50A cable is the oly choice, both for amps and 4 wire vs 3.

Gary

That was kind of my feeling about it. When I am plugging into a 20A outlet at home, do I really have to schlep out that big, heavy 50A cord, when the 30A cord will be about the same :-\
 

Shayne

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Bernie  When I've done this I used a 10 Gauge extention  cord also plugged into a receptacle with 10 gauge wire running to it.  Most places only have 12 gauge but mine was designed that way.  Also I always tried to keep it to 25 foot.  But that's just me on the side of caution.
 

Pat

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I have a 30 amp, built-in cord that's probably 25' long.  If I have to run an extension cord, I'm interpreting this topic as saying that I should use a 50amp extension cord plus an adapter to my 30amp built-in cord? 

Then I'd like to ask this.  I don't like the built-in cord, because it's difficult to get it in and out of the space in which it's crammed for storage.  I just push or pull it through an opening, and apparently the cord crumples up into a box when stored.  When it's cold, it's difficult to manipulate.  So, I asked the manufacturer to remove the 25' cord and just put in a pigtail that sticks out a bit, and I'd always carry and use an extension.  Their legal department told them they could not do that, because it's dangerous to use an extension cord.  Does that sound correct?  They made up and gave me a short pigtail, but they refused to install it.  Told me I'd have to hire somebody else to do it.  Since the connection is barely reachable without disassembling the kitchen cabinets and counter and sink, couldn't somebody just cut off the last 20 feet or so and wire a plug to the built-in cord?  Then all I'd have is a foot or two to cram back into the storage box, and I could use a 50amp extension cord plus adapter per this thread.  No?

--pat
 

Jim Godward

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Pat,

No.  First of all a 30 amp cord will be adequate for you since you already have the 30 amp cord and service.

If you are really serious about always using a detachable cord, have an electrician install a Boat outlet and have the mating connector installed on the cable that will be removed.  If you go to Boater's World at Jansen Beach, they can show you what I am talking about and can probably recommend someone to install them.  There are lots of boat shops in the area.  Or you can wait till late March when we get there and maybe I can help resolve the issue for you.  VBG

They are not cheap but they are safe and will do what you want done.  If you look around the RV park you may also see them as some RVs already use them.  I have thought about changing my MH to them but need to either get serious or forget it!  BG
 

Mike Goad

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Their legal department told them they could not do that, because it's dangerous to use an extension cord.  Does that sound correct?  They made up and gave me a short pigtail, but they refused to install it.  Told me I'd have to hire somebody else to do it.

It's not that it's necessarily dangerous.  It appears to me they're not willing to take the chance of a legal liability, just in case.
 

John From Detroit

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Some general musings on wire sizes.

Normally when they rate wire, they think in terms of a 100' run, How big a wire will it take to carry the load 100' without dropping too much voltage, There are other factors as well but this is a common one.

RV Cords tend to be heavy enough for a 100' run 

That said, it never hurts to use a size or two larger.  SMALLER does hurt, they have a name for a too small wire---- FUSE

I've used some long cords on occasion w/o issue
 

Jeff

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Another great thing about QZ. My extension cords will not reach!!! ;D ;D ;D
 
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