Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
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 08-16-2010, 09:19 PM   #1
Senior Member
 
Wanabee FTer's Avatar
 
Gulf Streamers Club
Ford Super Duty Owner
Join Date: Jul 2010
Location: Golden Village Palms, CA
Posts: 1,988
Blog Entries: 12
Is my motor home wired for 30 amp or 50 amp service?

Can someone please explain to me how my 30 amp coach electrical system works. My 30 amp shore power line will allow front or rear a/c to operate on a selector switch, but when I plug my shore power line into the coaches receptacle, both a/c units will operate on the generator. I have a 5000 watt Onan genset. Doesn't that mean the coach is wired for 50 amp service?
__________________

__________________
John
'98 Gulf Stream Sunsport 325, 7.5L Banks Power Pack, Koni FSD's, Air Bags, ReadyBrute Elite,
2000 Honda Accord

Wanabee FTer 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 08-16-2010, 09:45 PM   #2
Senior Member
 
Dmiles's Avatar
 
Appalachian Campers
Forest River Owners Club
Ford Super Duty Owner
Join Date: May 2009
Location: Suffolk, VA
Posts: 473
Wannabe, if your shore power plug has 3 "blade" type connectors that are parallel to each other and a separate round ground connector, then that is a 50 amp plug, and you likely have an open circuit somewhere on one of the hot connections. It would most likely be a blown fuse or circuit breaker, but it could also be a broken wire, or even a bad connection in the plug.

A 30 amp plug will have 2 blade type connectors and one separate ground that will be round, but I would think it would be highly unlikely that you would have that on your coach.

Let me ask you....when you use your generator, do you have to plug your shore power plug into a receptacle that is in your coach? If not, then you have a transfer switch, and that could indeed also be where your problem is.

A 50 amp service is simply 2 separate 125 volt circuits, so this is why I suspect you have an open circuit, blown fuse or tripped breaker. Here is a link that will 'splain it a little better than I can, and after reading this you will definitely know what you are wired for, and should get you on the right track.

http://www.dasplace.net/RVWiring/wiring.html

Best of luck to you.
__________________

__________________
2011 Winnebago Vista 30W
Duane, Precy, 9 year old son Matt, and Abby, our American Eskimo.
Dmiles is offline   Reply With Quote
Old 08-16-2010, 09:51 PM   #3
Senior Member
 
Wanabee FTer's Avatar
 
Gulf Streamers Club
Ford Super Duty Owner
Join Date: Jul 2010
Location: Golden Village Palms, CA
Posts: 1,988
Blog Entries: 12
Sorry I may not have explained this properly. I have a 30 amp shore power line with no 50 amp line. I must plug my 30 amp shore line into my coaches 30 amp receptacle for the genset to work. So I am assuming my generator supplies 50 amps to be able to run both a/c units?
__________________
John
'98 Gulf Stream Sunsport 325, 7.5L Banks Power Pack, Koni FSD's, Air Bags, ReadyBrute Elite,
2000 Honda Accord

Wanabee FTer is offline   Reply With Quote
Old 08-16-2010, 09:59 PM   #4
Senior Member
 
Theberrys's Avatar


 
National RV Owners Club
Join Date: Jun 2009
Posts: 2,605
Your generator is 5000 Watts. Given the formula P=IV then 5000 Watts/120 Volts= 41.6 Amps. So your Generator can provide more Amps than your Shore Power Cable at 30 Amps. This doesn't mean you are wired for 50 Amps. 30 Amp service is a single Phase of AC, 50 Amp Service is two Phases of AC. So you are probably wired for a single Phase. It's just that your generator provides more current than the shore cable.

Dick
__________________
1999 Tradewinds 7372 Cat 3126
Albuquerque, NM
Theberrys is offline   Reply With Quote
Old 08-16-2010, 10:14 PM   #5
Registered User


 
Monaco Owners Club
Join Date: May 2009
Posts: 3,198
If you look close at your genny, you will see that it has 2 breakers. My 5500 has a 30 amp and a 20 amp breaker.

Your shore power (30 amps) can run either A/C, but not both. Your EMS (Electricity management system) knows this.
your genny CAN run both, 30 amp breaker to the coach and front AC, 20 amp breaker to the rear AC. Your EMS knows this too, and internally makes the proper connections automatically to make it happen.

On my 99 fleetwood, the EMS is pretty sophisticated, and it can run both A/C's on 30 amps, it just never starts both compressor at the same time
__________________
JimM68 is offline   Reply With Quote
Old 08-16-2010, 10:15 PM   #6
Senior Member
 
Theberrys's Avatar


 
National RV Owners Club
Join Date: Jun 2009
Posts: 2,605
Here is another way to tell. Look in your AC Breaker Box. If you don't find a Ganged 50 Amp Breaker then you'll probably find a Single 30 Amp Breaker or perhaps a Single 40 Amp Breaker. It should be on the left and labeled Main. Picture of the 50 Amp breaker attached.

Dick

BYW 30 AMP service is really that 30 AMP (Single Phase), but 50 AMP Service is really two 50 AMP lines providing a total of 100 AMPS (Two Phases).
Attached Thumbnails
Click image for larger version

Name:	50 Amp Breaker.jpg
Views:	101
Size:	216.3 KB
ID:	4998  
__________________
1999 Tradewinds 7372 Cat 3126
Albuquerque, NM
Theberrys is offline   Reply With Quote
Old 08-16-2010, 10:16 PM   #7
Registered User


 
Monaco Owners Club
Join Date: May 2009
Posts: 3,198
Quote:
Originally Posted by Theberrys View Post
Your generator is 5000 Watts. Given the formula P=IV then 5000 Watts/120 Volts= 41.6 Amps. So your Generator can provide more Amps than your Shore Power Cable at 30 Amps. This doesn't mean you are wired for 50 Amps. 30 Amp service is a single Phase of AC, 50 Amp Service is two Phases of AC. So you are probably wired for a single Phase. It's just that your generator provides more current than the shore cable.

Dick
Be careful with that one. 50 amp service is 2 fused circuits of 50 amps each.
Not nessesarily 2 phases. Going across the 2 hot leads on a 50 amp plug will often NOT produce 220 volts, but rather, zero volts.
__________________
JimM68 is offline   Reply With Quote
Old 08-16-2010, 10:29 PM   #8
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,065
A properly wired 50A service will always produce 220v across the two hots. But occasionally you will find one wired such that it does not. It may still provide two 50A hots, or it may be something less. I've also seen outlets wired to produce 220v, but at less than 50A - could be 40A or even 30A. Most people would never know the difference since pretty much everything would still work fine.
__________________
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 online now   Reply With Quote
Old 08-16-2010, 10:31 PM   #9
Senior Member
 
Theberrys's Avatar


 
National RV Owners Club
Join Date: Jun 2009
Posts: 2,605
The main breaker really tells the story. Properly wired 50 amp service is just like your house two phases.

Dick
__________________
1999 Tradewinds 7372 Cat 3126
Albuquerque, NM
Theberrys is offline   Reply With Quote
Old 08-16-2010, 10:31 PM   #10
Senior Member
 
Wanabee FTer's Avatar
 
Gulf Streamers Club
Ford Super Duty Owner
Join Date: Jul 2010
Location: Golden Village Palms, CA
Posts: 1,988
Blog Entries: 12
Thank you all for replying so quickly to my post. It sounds like my coach is wired only for 30 amp service, wishful thinking it could be easily converted to 50 amp to run both a/c's at the same time on shore power
__________________
John
'98 Gulf Stream Sunsport 325, 7.5L Banks Power Pack, Koni FSD's, Air Bags, ReadyBrute Elite,
2000 Honda Accord

Wanabee FTer is offline   Reply With Quote
Old 08-16-2010, 10:38 PM   #11
Senior Member
 
Dmiles's Avatar
 
Appalachian Campers
Forest River Owners Club
Ford Super Duty Owner
Join Date: May 2009
Location: Suffolk, VA
Posts: 473
Well by attempting to answer a question, I learned something! I just assumed any coach that had 2 ACs would be wired for 50 amp service, with one of the hot circuits feeding only the rear air. Since I've never owned a rig wit 2 ACs, I just assumed they were all wired the same.

I assume it's to keep costs down, that's the only reason I can think of that they would wire a rig so that both ACs can't run off shore power.
__________________
2011 Winnebago Vista 30W
Duane, Precy, 9 year old son Matt, and Abby, our American Eskimo.
Dmiles is offline   Reply With Quote
Old 08-16-2010, 10:44 PM   #12
Senior Member
 
Dmiles's Avatar
 
Appalachian Campers
Forest River Owners Club
Ford Super Duty Owner
Join Date: May 2009
Location: Suffolk, VA
Posts: 473
Quote:
Originally Posted by Wanabee FTer View Post
Thank you all for replying so quickly to my post. It sounds like my coach is wired only for 30 amp service, wishful thinking it could be easily converted to 50 amp to run both a/c's at the same time on shore power
Well it could be done, but sounds like it would be a bit of a project. Still seems strange to me that a manufacturer would do that. I do remember at the Rally in Louisville many big rigs running their generators, but I figured it was because only 30 amp service was available, so they had to fire up the gen to run that second air. It was sure hot enough for it! But again I never knew that they would wire a 2 AC rig for 30 amp.

Someone who knows more about 50 amd rigs since I have never owned one but who knows, maybe someday. Is this fairly common, or more rare to see rigs with 2 ACs wired for 30 amp, only to be able to run both with the generator?
__________________
2011 Winnebago Vista 30W
Duane, Precy, 9 year old son Matt, and Abby, our American Eskimo.
Dmiles is offline   Reply With Quote
Old 08-17-2010, 07:44 AM   #13
Senior Member
 
Join Date: Jul 2010
Location: Wenatchee, WA.
Posts: 297
Send a message via Yahoo to frederick w
Hi
On my Onan 5500, I have a 30 amp breaker and a 20 amp breaker with two Roof A/c.
Does this mean I have a 50 amp service on my
2000 Flair?

Thanks
Fred Rubio from Pasco, WA.
__________________
frederick w is offline   Reply With Quote
Old 08-17-2010, 08:12 AM   #14
Senior Member
 
Join Date: Nov 2006
Location: Chalreston, S.C.
Posts: 288
Quote:
Originally Posted by frederick w View Post
Hi
On my Onan 5500, I have a 30 amp breaker and a 20 amp breaker with two Roof A/c.
Does this mean I have a 50 amp service on my
2000 Flair?

Thanks
Fred Rubio from Pasco, WA.
I thought we settled this, the answer is no. If you have a 30 amp incoming power cord you have a 30amp motorhome that CANNNOT run two air conditioners at the same time. You will have a selector switch to choose which AC to run or a load shedding system like Intellitec that will allow the two air conditioners to run alternately. One compressor will stop and the other will start up, but never together. In most motorhomes generators are sized in wattage to be able to run both AC's at the same time. A lot o people have done a work around where they have wired their rear A/C to a separate 20amp cable so they can plug in their rear air conditioner using the 20 amp (household) outlet found on the campground's power pedestal.
__________________

__________________
buck62 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
Sightseer 35J- 2 A/Cs on 30 amp service? Lincoln4 Winnebago Industries Owner's Forum 14 09-27-2013 11:52 AM
Two A/C units on a 30 amp service. Hurricaner Damon 20 05-18-2009 01:31 PM
Redlands Truck and RV Awarded Top Customer Service Award DriVer RV Industry Press 0 03-21-2009 01:08 PM
Power Line One Panel Limits One Leg 50 Amp circuit to 30 Amps SteveG Winnebago Industries Owner's Forum 17 03-05-2008 05:43 PM
A question about 30/50 amp service Dmax Newmar Owner's Forum 6 09-27-2007 08:12 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:09 PM.


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