Go Back   iRV2 Forums > MOTORHOME FORUMS > Toads and Motorhome Related Towing
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-10-2012, 04:07 PM   #1
Senior Member
 
Join Date: Mar 2011
Posts: 133
Ground for dolly

I just added a 12 awg wire for the feed from the brake controller to the trailer plug (Winnebago/Workhorse did not include it until after mine was built).
Although a single axle brake system would normally be ok with 14 awg, I thought it best to go up a gauge due to the length of the run. My dolly has two grounds to its 7 pin plug, a 14 awg for lights and a 12 for brakes, (both to the same pin).
The motorhome ground is 14 awg. As the ground from the rear of the motorhome to wherever carries any and all current going to and from the dolly (lights and brakes) should I add a second or heavier wire to the frame from the plug?
__________________

__________________
Bill
Peddler is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-17-2012, 06:23 PM   #2
Senior Member


 
Join Date: Apr 2012
Posts: 1,495
Current flow uses the complete circuit. The wire gauge must be sized appropriatly for both sides of the circuit.

Actually if one has several positive wire leads from the RV with 14 ga wire going to different components on the towed vehicle and the single ground back to the RV is only 14ga then the entire system is using a single 14 ga circuit for the return path. A chain is only as strong as the weakest link and the single 14 ga ground wire is that weak link in this scenario, and if the combined current in all of the 14ga exceeds the capacity of the return path, expect trouble. One needs to know the current requirement for each leg of the circuit and the length of the wire and size accordingly. Of course all circuits need to be fused appropriatly based on wire size of the weakest link.

Hope this helps. Many people forget about appropriate sizing the ground return wire. Mechanical connections between the RV and towed vehicle should never be factored in electrical grounding requirements.
__________________

__________________
Libero is offline   Reply With Quote
Old 05-19-2012, 08:23 AM   #3
Senior Member
 
Join Date: Nov 2005
Posts: 3,336
Quote:
Originally Posted by Peddler View Post
I just added a 12 awg wire for the feed from the brake controller to the trailer plug (Winnebago/Workhorse did not include it until after mine was built).
Although a single axle brake system would normally be ok with 14 awg, I thought it best to go up a gauge due to the length of the run. My dolly has two grounds to its 7 pin plug, a 14 awg for lights and a 12 for brakes, (both to the same pin).
The motorhome ground is 14 awg. As the ground from the rear of the motorhome to wherever carries any and all current going to and from the dolly (lights and brakes) should I add a second or heavier wire to the frame from the plug?
I think if you look a little deeper you'll find the wires were installed on the incomplete chassis. Winnebago did not extend them from the frame to the trailer socket at the rear of the coach.

When the incomplete chassis comes to the body builder the wires for the trailer hitch are folded back and taped inside the main wiring harness on the left frame rail. Winnebago installs the socket at the rear of the coach and extends the wires from the main harness. For some reason they generally extended only the wires for the tail lights and brake lights. The ground, power for electric brakes and power for interior trailer lighting and battery charging are left taped in the harness.

I ran into the same problem on our 01 Ford chassis. When I asked why they only extended some of the wires they didn't have a good answer. At the time they were expecting the customer and the dealer to have a conversation as to whether the customer was planning on pulling a trailer or dolly with electric brakes or internal lighting. The dealer was supposed to extend the necessary wires to the hitch socket.

I think they had so many customers that did the same thing you've done they finally decided to extend all the wires.
__________________
Hikerdogs
2013 Adventurer 32H
Hikerdogs is offline   Reply With Quote
Old 05-19-2012, 08:26 PM   #4
Senior Member
 
Join Date: Mar 2011
Posts: 133
They only put the brake wire on the Ford chassis, Workhorse included it (folded up like Ford's) in 2006 or 2007. I looked at 2007 wiring drawings and they also changed the plug to 7 pin and, more important to my question, changed the ground wire to 12 AWG. Controller mfg says 14 is ok for single axle brakes but I think they are only talking about the feed wire and are not considering the added other loads for the ground. I will add a 12 awg ground wire to a frame connection and tap the existing tail light ground to it.

Thanks to both of you for your responce.
__________________
Bill
Peddler is offline   Reply With Quote
Reply

Tags
dolly



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


» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:31 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.