Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
Old 08-26-2013, 06:27 PM   #21
Senior Member
 
Witch Doctor's Avatar
 
Join Date: Feb 2012
Location: Clarksville Va.
Posts: 10,422
Quote:
Originally Posted by BarryD0706 View Post
We are talking about the case where there is some kind of short (eg, conduction path) somewhere between the 50-amp pedestal plug and the 30-amp breaker in your RV. So for example, you have a cord that plugs in at your RV (not permanently mounted) and something shorts across that cable plug at the RV end. It doesn't matter what's going on with the breaker in your RV. The only other breaker is 50 amps and the 30-amp cord will melt before that 50-amp breaker trips. Does that help?
If your unlikely exampled happened it wouldn't make any difference what size the wire is, it also would melt. By the time the so call cord would melt it would trip the 50 amp breaker anyway from shorting out.......That can also happen if you were plugged into a 30 amp outlet. If you melt the cord it makes no difference.If you get a short at the RV end you will trip that 50 amp breaker also.....
__________________
Coachmen M/H
Concord
2018 / 300 DSC

Witch Doctor is offline   Reply With Quote
Old 08-26-2013, 07:01 PM   #22
Senior Member
 
Join Date: Nov 2012
Location: X
Posts: 2,781
I didn't say direct short. Perhaps the RV loads are pulling 25 amps and that "conduction path" is pulling 20 amps. No beaker will trip.
BarryD0706 is offline   Reply With Quote
Old 08-26-2013, 07:04 PM   #23
Senior Member
 
Join Date: Apr 2011
Posts: 313
To the OP yes its fine. people do it every day. Do not be concerned reading all the what if stories. There is such a fraction of a chance of anything happening its not even worth the thought. IMO

To the other guys. 30' of #10 wire with a 50 amp draw is only a 2.57% voltage drop. Which is within recommended guidelines. Would I want to run this continuously? Not really, I would probably run a heavier gauge, but we are not running 50 amps thru this cord. we are only running 30. As mentioned the cord from the pedestal to the RV does have a potential to be damaged. However, we know it can handle the 50 amps. and at a 55amp load its 2.82% voltage drop (still withing recommended guidelines). Now the breaker should open at some point with this much load on it. Is the cord going to melt down? I say no. Now if you get into 50' of wire I would say we could be pushing the safety margin a bit, but then again I see this as such a small risk. I would see a catastrophic failure as more of a possibility and would trip the breaker rather quickly. Am I thinking wrong here?
Acableguy06 is offline   Reply With Quote
Old 08-26-2013, 07:22 PM   #24
Senior Member
 
Join Date: Apr 2011
Posts: 313
I'm going to interject a few more thoughts on the cord overload. How many of you plug a 16 or 14 ga extension cord into a 20 amp circuit? That's an overloaded cord. What about all the appliance or lamp fixtures you plug into the wall? Often a 18 or 16 ga. wire being plugged into a 15 or 20 amp circuit. Do you see where I am going here?
Acableguy06 is offline   Reply With Quote
Old 08-26-2013, 07:32 PM   #25
Senior Member
 
Join Date: Nov 2012
Location: X
Posts: 2,781
Quote:
Originally Posted by Acableguy06 View Post
I'm going to interject a few more thoughts on the cord overload. How many of you plug a 16 or 14 ga extension cord into a 20 amp circuit? That's an overloaded cord. What about all the appliance or lamp fixtures you plug into the wall? Often a 18 or 16 ga. wire being plugged into a 15 or 20 amp circuit. Do you see where I am going here?
Excellent point!
BarryD0706 is offline   Reply With Quote
Old 08-26-2013, 08:22 PM   #26
Denver, CO
 
garbonz's Avatar
 
Join Date: Jan 2013
Location: Denver, CO
Posts: 2,102
Quote:
Originally Posted by gljurczyk View Post
If your unlikely exampled happened it wouldn't make any difference what size the wire is, it also would melt. By the time the so call cord would melt it would trip the 50 amp breaker anyway from shorting out.......That can also happen if you were plugged into a 30 amp outlet. If you melt the cord it makes no difference.If you get a short at the RV end you will trip that 50 amp breaker also.....
X2. if you get a short enough to melt a 30 amp cord it gonna melt a 50 amp cord pretty soon. for normal situations the 30 amp main will prevent an overcurrent.

I wouldn't worry about, get a PI or Franks and an adapter and be happy.
__________________
2017 Fuse 23T
garbonz is offline   Reply With Quote
Old 08-26-2013, 08:59 PM   #27
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 23,269
I think this is the most likely scenario for a burned up cord with no (or late) breaker trip.

Corrosion at the wall socket of the camper.

A corroded, pitted connection can increase resistance (and thus current demand) at the socket that the 30 amp breaker inside the coach does not "see" (so it will not trip and end the high resistance short at the socket).

Temperature at the bad connection will increase at the wires until something gives (the wires, the socket, or the 50 amp breaker).
Attached Thumbnails
Click image for larger version

Name:	7-1-12007.jpg
Views:	84
Size:	19.6 KB
ID:	38714  
__________________
Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
Herk7769 is offline   Reply With Quote
Old 08-26-2013, 09:43 PM   #28
Senior Member
 
Join Date: Apr 2011
Posts: 313
Quote:
Originally Posted by herk7769 View Post
I think this is the most likely scenario for a burned up cord with no (or late) breaker trip.

Corrosion at the wall socket of the camper.

A corroded, pitted connection can increase resistance (and thus current demand) at the socket that the 30 amp breaker inside the coach does not "see" (so it will not trip and end the high resistance short at the socket).

Temperature at the bad connection will increase at the wires until something gives (the wires, the socket, or the 50 amp breaker).
Agree.
Acableguy06 is offline   Reply With Quote
Reply

Tags
50 amp, fema

Thread Tools
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

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 08:27 PM.