Go Back   iRV2 Forums > RV SYSTEMS AND TECHNOLOGIES FORUMS > RV Systems & Appliances
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 10-14-2006, 08:58 PM   #1
Junior Member
 
Join Date: Nov 2001
Location: Tucson, AZ
Posts: 8
My 5er is wired for 30 amp service. Some RV sites have both a 30 and a 50amp connection in the same box. Will there be less voltage drop in the trailer if I hook up to the 50 with an adaptor cord, when say using around 25 amps.
__________________

__________________
Tom from Tucson 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 10-14-2006, 08:58 PM   #2
Junior Member
 
Join Date: Nov 2001
Location: Tucson, AZ
Posts: 8
My 5er is wired for 30 amp service. Some RV sites have both a 30 and a 50amp connection in the same box. Will there be less voltage drop in the trailer if I hook up to the 50 with an adaptor cord, when say using around 25 amps.
__________________

__________________
Tom from Tucson is offline   Reply With Quote
Old 10-15-2006, 03:23 AM   #3
Community Moderator
 
RV Wizard's Avatar


 
Country Coach Owners Club
Appalachian Campers
Gulf Streamers Club
Join Date: Mar 2000
Location: Chattanooga, Tn.
Posts: 12,062
Tom, the voltage will be the same on either the 30 amp or the 50 amp with an adapter. Unless there is something wrong with the 30 amp circuit I don't see any advantage to using the 50 amp.
__________________
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7
RV Wizard is offline   Reply With Quote
Old 10-15-2006, 04:12 AM   #4
Senior Member
 
Join Date: Nov 2005
Posts: 3,191
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by RV Wizard:
Tom, the voltage will be the same on either the 30 amp or the 50 amp with an adapter. Unless there is something wrong with the 30 amp circuit I don't see any advantage to using the 50 amp. </div></BLOCKQUOTE>

Mike,

You are right, unless there is something wrong with the 30 amp circuit you shouldn't need to.

When I drove up the East Coast and through the Appalations to Ottawa during the brownouts that afflicted the East this past July, at about half the campgrounds I stayed the 30 amp would not hold during the brownouts. A dogbone to the 50 amp was the only way I could get by with my 30 amp coach. I have since purchased a Hughs Autoformer to get the voltage back up to spec also.

I guess you could say that on my July trip there was something wrong with the 30 amp circuits 50% of the time.

I had to run out and purchase a 50 to 30 amp dogbone at an inflated price at that time. I would advise anyone with a 30 amp coach to get a dogbone at their leisure so they can take advantage of the best price available and not wait until they absolutely need it. Then if and when they encounter a problem with the 30 amp they will be equipped to change over to the 50 if it is available before have to go site hopping. Site hopping is not much fun during a late night stop over with a Class A and I suppose it would be even less fun with a Fifth Wheel.

Kind regards,
__________________
Neil V
2001 Winnebago Adventurer WFG35U
NeilV is offline   Reply With Quote
Old 10-15-2006, 07:11 AM   #5
Moderator Emeritus
 
TXiceman's Avatar


 
Vintage RV Owners Club
Texas Boomers Club
Oklahoma Boomers Club
Ford Super Duty Owner
Join Date: Aug 2000
Location: Full Time, TX Home Base
Posts: 17,150
Blog Entries: 21
My trailer is a 30 amp rig, but I carry a 50/30 adapter with me. Mostly use the 30 amp plug, but on occassiona I will find that I have a bit higher voltage on the 50 amp side. It depends on how thw campground is wired and which side has the most load. Where we are now, I gt abot 3 to 4 volts on the 50 amp adapter in the summer when the voltage tends to run a bit lower. It keeps me running in extreme conditions.

Ken
__________________
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Standard Schnauzer and one small Timneh African Gray Parrot
TXiceman is offline   Reply With Quote
Old 10-15-2006, 01:36 PM   #6
Senior Member
 
Horsepowerfan's Avatar
 
Workhorse Chassis Owner
Join Date: Sep 2003
Location: Weare, NH, USA
Posts: 239
At the risk of sounding ignorant, I was under the impression that a 50 amp 4-prong outlet provided 240 volts. I thought that if I plugged my 30 amp/120 volt coach into a 50 amp receptacle using an adapter I could possibly overload the electrical system.

I hope I'm wrong about this because it would certainly be convenient to be able to plug into 50 amps with an adapter in a pinch or even to get cleaner power.

Does the 30 to 50 amp dogbone adapter step the voltage down to 120 in some way? What am I missing here? Could someone please explain?

Thank you!
__________________
Jim & Linda
'03 Winnebago Adventurer 35U (W22)
'06 Saturn Vue Toad
Horsepowerfan is offline   Reply With Quote
Old 10-15-2006, 01:46 PM   #7
Senior Member
 
DavidMc's Avatar
 
Join Date: Dec 2002
Location: On-The-Road
Posts: 134
Jim,
Although you will normally find that across the two "hot" legs the voltage is 240-volts, when you use a 50-to-30 connector you only are using one of those two legs.

A 50-amp connection has four prongs as you noted:
1. 120-volt hot left
2. 120-volt hot right
3. Neutral
4. Safety Ground

A 30-amp connection has three prongs:
1. 120-volt hot (could be either "left" or "right" - does not matter)
2. Neutral
3. Safety Ground

The adapter uses only one of the 120-volt hot leads (ignoring, ie not connecting, the other hot lead) plus the Neutral and Safety Ground.

Inside a 50-amp RV it is essentially like inside a house where some circuits are on one "leg" and some on the other -- both working against the neutral for 120-volts at the outlet. (Of course, in a house, an electric range/oven, household water-heater, or furnace will take advantage of the 240-volts that are possible).
__________________
David

My signature used to include a link to my personal web-site - - - however:
DavidMc is offline   Reply With Quote
Old 10-15-2006, 01:56 PM   #8
Senior Member
 
Horsepowerfan's Avatar
 
Workhorse Chassis Owner
Join Date: Sep 2003
Location: Weare, NH, USA
Posts: 239
Thank you, David, for the quick reply! I'm so thankful for the sharing of information I find on this website! I'm constantly learning new things.

A trip to the store for an adapter is now at the top of my "to do" list!
__________________
Jim & Linda
'03 Winnebago Adventurer 35U (W22)
'06 Saturn Vue Toad
Horsepowerfan is offline   Reply With Quote
Old 10-15-2006, 02:25 PM   #9
Senior Member
 
Horsepowerfan's Avatar
 
Workhorse Chassis Owner
Join Date: Sep 2003
Location: Weare, NH, USA
Posts: 239
Sorry, I just thought of another question. This pertains more to coaches that don't have an energy management system like ours does (which limits the power consumption to 30 amps), but I thought it may be important to others as it may be a safety issue.

If a coach's electrical system is only rated for 30 amps but is plugged into a 50 amp outlet using an adapter, is it conceivable that the 30 amp electrical system could draw up to 50 amps without the 50 amp pedestal circuit breaker tripping? If this is the case, could the electrical cord, transfer switch, and breaker or fuse panel inside the coach be subjected to excessive current (amps)? I may be being overly cautious here, as these adapters seem to be popular, but I just want to make sure there is no fire hazard.

Thanks, again, and I don't want to scare anyone!
__________________
Jim & Linda
'03 Winnebago Adventurer 35U (W22)
'06 Saturn Vue Toad
Horsepowerfan is offline   Reply With Quote
Old 10-15-2006, 02:45 PM   #10
Senior Member
 
DavidMc's Avatar
 
Join Date: Dec 2002
Location: On-The-Road
Posts: 134
Jim,
There is one area of risk, albeit very slight.

The coach/trailer/RV has a circuit breaker panel inside it with a "main" breaker that should be at the limit point for the coach's design (ie: either 30 or 50 amp).

Breakers 'officially' protect the wiring and connected devices that are "down stream" from them -- that is towards the user, away from the power source.

So, in theory, a 30-amp RV plugged into a 50-amp pedestal could burn up the cord from the pedestal to the RV's ciruit-breaker panel. However that would require the cord itself to draw current after the RV's internal breaker trips.

I do not worry about this when I plug in my 40-amp (yes: forty) RV cord with 50-amp style plug into a 50-amp pedestal. The internal breakers are for 40-amps (both legs), most cords in good repair will handle more than their official rating for a reasonable period of time. So far, I have not been able to trip a 30-amp breaker on a good pedestal, and I have never tripped the trailer's internal main breakers.
__________________
David

My signature used to include a link to my personal web-site - - - however:
DavidMc is offline   Reply With Quote
Old 10-15-2006, 03:01 PM   #11
Senior Member
 
Horsepowerfan's Avatar
 
Workhorse Chassis Owner
Join Date: Sep 2003
Location: Weare, NH, USA
Posts: 239
OOOHHHH! Now I get it! (The wife was right - she said to me "What about the breakers inside the coach?" - Need to learn to listen to her! )

Thanks very much for clearing that up for me.

By the way, in case you noticed, the wife has also been streamlining our signature line - that's why it's been changing each time we post!
__________________
Jim & Linda
'03 Winnebago Adventurer 35U (W22)
'06 Saturn Vue Toad
Horsepowerfan is offline   Reply With Quote
Old 10-17-2006, 06:41 AM   #12
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,085
on a properly wired power pole, the 50A outlet will be on an entirely different circuit (and power source) than the 30A outlet. Thus it may be less (or more) loaded than the 30A and so may show greater or lesser voltage. In older campgrounds, it is not unusual for the 30A wiring to be old and stretched to its limits while the 50A wiring is new and geared toward more up-to-date power demaqnds.

So yes, if you are experiencing low voltage or other problems on the 30A outlet, it's worth checking the 50A outlet for better supply.

With a 50-&gt;30 adapter, you are using only 30% of the 50A outlets maximum rated capacity. If the 50A circuit is not being too badly loaded down by neighboring rigs, chances are you will have good solid power available.

In a poorly wired park, all bets are off. All you can do is try it and see if it is any better.
__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is offline   Reply With Quote
Old 10-21-2006, 02:30 PM   #13
Senior Member
 
Join Date: Feb 2002
Location: Aguanga, CA, USA
Posts: 238
I'm not sure of this, so someone please correct me if I'm wrong. But doesn't a 50 amp service just give a total of 50 amps in the two legs, i.e., 25 amps in each. Thus aren't you actually limited to 25 amps when using a 50 to 30 amp adapter?
__________________
jspande is offline   Reply With Quote
Old 10-21-2006, 03:58 PM   #14
Administrator in Memoriam
 
Hitchhiker's Avatar


 
Appalachian Campers
Join Date: Jan 2000
Location: Buladean, NC
Posts: 8,127
Each leg of a properly wired 50 amp RV circuit will be capable of providing a full 50 amps to each leg of the RV for a total of 100 amps. You'll notice your breakers on the RV's service entrance panel are each 50 amps and are mechanically banded together. (If one trips electrically the other gets tripped mechanically).

In actual use, it'd be rare to attain the total 100 amps of these two circuits because of load imbalance.
__________________

__________________
'11 GMC Acadia SLT AWD
'11 GMC Sierra 1500 4x4 Extended Cab
Hitchhiker is offline   Reply With Quote
Reply



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


Similar Threads
Thread Thread Starter Forum Replies Last Post
how to run both a/c's on 30amp shore power ? Brady704 Winnebago Industries Owner's Forum 8 08-20-2008 08:39 AM
30amp or 50amp?? Greybeard Winnebago Industries Owner's Forum 12 07-15-2008 09:57 AM
30amp to 50amp adapter Logthumper Gear and Product Discussions 5 02-21-2008 04:05 PM
30amp or 50amp?? RV Systems & Appliances 12 12-31-1969 07:00 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 05:10 AM.


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