Thread Tools Search this Thread Display Modes
Old 06-27-2012, 08:18 PM   #1
2 Rivet Member
1970 31' Sovereign
Burnsville , North Carolina
Join Date: Dec 2011
Posts: 60
How do I wire AS for an RV hook-up that is 75' away?

Hello out there!
I am about to move my 1970 Sovereign to its more or less permanent parking spot. It's a 30amp system and we will not be using the air conditioner. The RV plug-in box is 75 feet away. I want to replace the old power cord which is only about 20 feet long. Any advise on what gauge wire i need to use to go 75 feet? Also, I have installed a new electric-only H20 heater and am planning on hooking it up to a switch inside the AS and then running a 75' cord to the RV plug-in. Same question here as far as wire gauge. Have any of you replaced the old breaker box in the AS to accommodate a separate circuit for your H20 heater?
Thanks in advance for any help you can give. I have done most of the rehab on this unit myself but don't know much about electricity.

CeloNC is offline   Reply With Quote
Old 06-27-2012, 08:31 PM   #2
Rivet Master
AIR-Quarius's Avatar
1970 27' Overlander
Espanola , Full Timer
Join Date: Jun 2007
Posts: 1,752
Images: 39
Send a message via Yahoo to AIR-Quarius Send a message via Skype™ to AIR-Quarius
The bigger the better!

AIR-Quarius is offline   Reply With Quote
Old 06-27-2012, 08:57 PM   #3
Rivet Master
HowieE's Avatar
1991 34' Excella
Princeton , New Jersey
Join Date: Aug 2003
Posts: 6,925
Images: 12
You can check with any electrical supply house on the size of the wire. If your heater is close to 20 amps would assume at least a #10 wire.

Keep in mind that the wire size will have to go all the way back to your panel in the house.
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles

HowieE is offline   Reply With Quote
Old 06-28-2012, 02:25 PM   #4
Wise Elder
Jammer's Avatar
2010 30' Classic
Vintage Kin Owner
South of the river , Minnesota
Join Date: Dec 2009
Posts: 4,129

10 gauge will work especially if you are not using the air conditioner. There will be some voltage drop when heavy loads are present.

I have a 6 gauge 60' cord that I sometimes use. Works great but it is heavy and awkward. I salvaged it from a silo unloader at a farm. To purchase a cable like that new would be prohibitively expensive with today's copper prices.

If you are parking permanently you're better off moving the power to a closer location and burying the wire. Then it only has to be done once. The flexible cable will only last a few years in the sun while buried type UF cable will last 50 years or more.
Jammer is offline   Reply With Quote
Old 06-28-2012, 02:33 PM   #5
3 Rivet Member
newsgauger's Avatar
1976 Argosy 28
Milton , Ontario
Join Date: Jul 2010
Posts: 144

Hi Bill,

Jammer is right on, by mentioning trenching in a new line.

You would not be happy of feel safe by running large gauge extention cord(s) along the ground. After all someone might mistakenly cut into the cable and electrocute themselves.

I'm all for burying it the 75'.

newsgauger is offline   Reply With Quote
Old 06-28-2012, 03:34 PM   #6
Rivet Master
68 TWind's Avatar
1968 24' Tradewind
Oxford, , Mississippi
Join Date: May 2009
Posts: 1,461
If you are sure you not going to move the trailer, I would suggest that you bury the proper size cable and hard wire it into the box on the trailer. If you don't want to do that you can buy a box like they use in campgrounds (Home Depot has them) and set it up close to the trailer. The cover will protect the plug from the elements.
Bruce & Rachel
68 Trade Wind
2001 Toyota Tundra
68 TWind is offline   Reply With Quote
Old 06-29-2012, 07:51 AM   #7
2 Rivet Member
1970 31' Sovereign
Burnsville , North Carolina
Join Date: Dec 2011
Posts: 60
As usual, the forum is very helpful. Thanks for that input. The problem I have with trenching is that I live in the mountains and am likely to run into solid rock. When our underground power was put in, they had to blast through several feet. So, that's why i am thinking of going above ground. The actual distance is closer to 75' and I am think of suspending the cable off the ground with some small poles and marking it well so no one will trip. Do you guys think 10 gauge is okay? Thanks. -Bill
CeloNC is offline   Reply With Quote
Old 06-29-2012, 08:41 AM   #8
Rivet Master
Currently Looking...
Gainesville , Florida
Join Date: Jul 2005
Posts: 6,801
Blog Entries: 2
Can you run the cable through plastic pipe to protect it? Jim
xrvr is offline   Reply With Quote
Old 07-01-2012, 09:43 AM   #9
4 Rivet Member
ddruker's Avatar
2000 27' Safari
Palo Alto , California
Join Date: Apr 2012
Posts: 261
Images: 1
I second the above recommendations- run the supply line to a location close to your trailer either through direct burial cable, or if that is impossible run through PVC conduit either below or above ground. Home depot has all the materials you need to do this and it's an easy project.

The key thing is you want to protect your supply cable from getting damaged - either from animal chewing, sun/weather, or any other accidental damage. You don't want to wake up to fried raccoon or dog one morning from them chewing through your cable.

Last - to your original question - three conductors of 10-gauge wire is absolutely adequate for a 30 amp circuit running 75 feet - you need hot, neutral and ground conductors, and for simplicity of discussion you should get 10 gauge for each of them. Assuming you run your cable in conduit, I would use 2 inch schedule 40 PVC conduit - underground is better, but above ground is ok.

You will experience an approximately 5 volt drop in voltage over 75 feet using 10 gauge conductors - which means it's probably ok to run your AC if you have adequate voltage where you are starting your run.
ddruker is offline   Reply With Quote
Old 07-02-2012, 02:42 PM   #10
2 Rivet Member
1970 31' Sovereign
Burnsville , North Carolina
Join Date: Dec 2011
Posts: 60
So, what about using 8gauge wire instead?
CeloNC is offline   Reply With Quote
Old 07-02-2012, 02:52 PM   #11
Rivet Master
TG Twinkie's Avatar
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 5,316
Images: 2
Blog Entries: 5
8 gauge will work.

Knowledge: "A gift to be shared. A treasure to receive."
TG Twinkie is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 10:38 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.