RV.Net Open Roads Forum: Tech Issues: What gauge wire do I use

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > What gauge wire do I use

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 5  
Prev  |  Next
Sponsored By:
pauldub

North of Seattle

Senior Member

Joined: 11/01/2005

View Profile


Offline
Posted: 07/10/19 07:20pm Link  |  Quote  |  Print  |  Notify Moderator

The NEC requires that you use 10 AWG with a 30 amp breaker. This is a safety requirement so that the wire doesn't burn up before the breaker trips. The NEC also makes recommendations on how much voltage drop one might allow and it's never more than 5%. If you are unable to know what the load really is, I guess you just have to assume that it's going to be 30 amps and go with 6 AWG wire. If you determine what the load actually is, then you can determine if 8 AWG is big enough. Either way, the wire is probably going to cost more than you would like.

KD4UPL

Swoope, VA

Senior Member

Joined: 03/16/2008

View Profile



Good Sam RV Club Member

Offline
Posted: 07/10/19 07:30pm Link  |  Quote  |  Print  |  Notify Moderator

To meet code for 30 amps #10. Nobody really calculates voltage drop on interior residential circuits because they aren't long enough for it to matter.
The NEC RECOMMENDS that you don't exceed 5% total voltage drop from the service to the end device. They also RECOMMEND no more than 3% drop in a circuit or feeder. I have a Southwire voltage drop app on my phone, I use it just about every day. For your application: 200', 30 amps, 120v you would need #4 copper to be under 3% and #6 copper to be under 5%.

MFL

Midwest

Senior Member

Joined: 11/28/2012

View Profile



Good Sam RV Club Member

Offline
Posted: 07/10/19 07:48pm Link  |  Quote  |  Print  |  Notify Moderator

Agree ^^^^200 ft is a long ways, plus another 30 ft of shore power cord. I did same as you want, used 75 ft of #8, plus my shore power cord. With some lights, converter/charger, and 15K AC, my voltage drops to 112 on a hot day. In your case #6 would be minimum. It is harder to work with.

Jerry





MEXICOWANDERER

las peñas, michoacan, mexico

Senior Member

Joined: 06/01/2007

View Profile


Offline
Posted: 07/10/19 08:10pm Link  |  Quote  |  Print  |  Notify Moderator

Complicated? For sure. There are motor start amperage complications you don't want to deal with. They'll whack you with repairs costing hundreds of dollars.

The correct answer is 6 AWG for a 30 amp rig. Violate it at your own risk. Not appropriate to place a happy face here.

Campin LI

Long Island

Full Member

Joined: 02/09/2011

View Profile



Good Sam RV Club Member


Posted: 07/10/19 08:12pm Link  |  Quote  |  Print  |  Notify Moderator

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.

GordonThree

Northern Michigan

Senior Member

Joined: 05/19/2013

View Profile


Offline
Posted: 07/10/19 08:23pm Link  |  Quote  |  Print  |  Notify Moderator

Campin LI wrote:

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.


8 or 10 would be fine, but do it right, do it once... if you go with 6/3 (4 wires), you can technically upgrade to a 50 amp socket at the end of it, if you get a bigger trailer sometime down the road. or two 30 amp sockets, if you want to add a spot for a guest.

Even if you dont see a bigger rig in the future, the heavier the wire, the better everything will work at the end of it. If you want to run your rooftop air, the electric hot water and say microwave at the same time, the heavier the wire the better.


2013 KZ Sportsmen Classic 200, 20 ft TT
2017 Ram 2500 4x4, 6.4 HEMI, 4.10 / Auto

Campin LI

Long Island

Full Member

Joined: 02/09/2011

View Profile



Good Sam RV Club Member


Posted: 07/10/19 08:36pm Link  |  Quote  |  Print  |  Notify Moderator

GordonThree wrote:

Campin LI wrote:

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.


8 or 10 would be fine, but do it right, do it once... if you go with 6/3 (4 wires), you can technically upgrade to a 50 amp socket at the end of it, if you get a bigger trailer sometime down the road. or two 30 amp sockets, if you want to add a spot for a guest.

Even if you dont see a bigger rig in the future, the heavier the wire, the better everything will work at the end of it. If you want to run your rooftop air, the electric hot water and say microwave at the same time, the heavier the wire the better.


At the end of the day, I know you are right.

Thank you!

dieseltruckdriver

Black Hills of SD

Senior Member

Joined: 08/24/2005

View Profile


Offline
Posted: 07/10/19 09:00pm Link  |  Quote  |  Print  |  Notify Moderator

Campin LI wrote:

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.

I understand what you are saying about the expense. I only had a 100' run and went with 6 ga. just to avoid the voltage drop. Only buy wire once, and that way you don't regret not spending a little more later.


2000 F-250 7.3 Powerstroke
2018 Arctic Fox 27-5L


MEXICOWANDERER

las peñas, michoacan, mexico

Senior Member

Joined: 06/01/2007

View Profile


Offline
Posted: 07/10/19 10:48pm Link  |  Quote  |  Print  |  Notify Moderator

Campin LI wrote:

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.



[image]

Ka Chunk

Ka Chunk

Ka Chunk

Smoke

3 tons

CA.

Senior Member

Joined: 03/13/2009

View Profile


Offline
Posted: 07/10/19 11:31pm Link  |  Quote  |  Print  |  Notify Moderator

MEXICOWANDERER wrote:

Campin LI wrote:

OK, 6 guage it is and yes this is a lot more expensive than I imagined.

Before I spend this kind of money, what are the odds I would draw so much power that 6 is required. In other words, would normal everyday rv use require 6 gauge wire or would 8 be fine.

Thanks again.



[image]

Ka Chunk

Ka Chunk

Ka Chunk

Smoke


Indeed, air conditioner windings cost a heap...

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 5  
Prev  |  Next

Open Roads Forum  >  Tech Issues

 > What gauge wire do I use
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2019 CWI, Inc. © 2019 Good Sam Enterprises, LLC. All Rights Reserved. | Terms of Use | PRIVACY POLICY | YOUR PRIVACY RIGHTS