Reply
 
Thread Tools Search this Thread Display Modes
 
Old 03-17-2020, 03:59 PM   #61
Winnebago Master
 
powercat_ras's Avatar
 
Join Date: May 2015
Location: Manhattan, Kansas USA
Posts: 758
I'll try to make my point on why thousands of us are using 50 to 30 adapters on RVs and Travel Trailers without any known cases of there ever being a fire or persons being injured because of doing this more clearly ...

All of the normal loads that would be put behind the 50 to 30 amp adapter are limited to 30 amps by the 30 amp main breaker in a RV or Travel Trailer. That's all the non current limited dogbones should be used for is to feed things that are current limited to 30 amps by a breaker or fuse.

There is no way for a RV user to put a load between 30 and 50 amps on the portion of the circuit between the dogbone and the 30 amp main breaker, that would cause the RV cord to exceed it's 30 amp rated load.

If the part of the circuit ahead of the 30 amp breaker has a hard fault due to cord damage or abuse or a catastrophic automatic transfer switch contactor failure that would trip a 30 amp breaker it will also trip a 50 amp breaker.

All that said ...

I totally agree that no one should ever use a 50 to 30 adapter to feed a 30 amp cord fed multiple outlet breakout box on a job site UNLESS the breakout box has a 30 amp main fuse or breaker (most do not). A un-protected breakout box must be current limited to 30 amps so you don't overload the 30 amp cord and that's what the dogbones with overcurrent protection that Grainger sells are intended for.
__________________
Randy - Manhattan, Kansas
2015 Vista 27N
2016 Honda HR-V
powercat_ras is offline   Reply With Quote
Old 03-17-2020, 04:16 PM   #62
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by powercat_ras View Post
All of the normal loads that would be put behind the 50 to 30 amp adapter are limited to 30 amps by the 30 amp main breaker in a RV or Travel Trailer. That's all the non current limited dogbones should be used for is to feed things that are current limited to 30 amps by a breaker or fuse.
Shorts are not normal loads and you're assuming the breaker in the RV functions and that any short is behind the breaker. As I said before unless you have a situation where your 30 amp main breaker (assuming it has one) inside the RV is tripping (or is defective), it's unlikely a normal load would cause an issue.

In the context of houses I couldn't count how many times I've seen too large of a breaker installed for the wire gauge. None of those houses had caught fire. That doesn't mean the breaker should not have been installed and it should not be changed. And houses are generally wired much better than RVs.
Goodspike is offline   Reply With Quote
Old 03-17-2020, 04:16 PM   #63
Winnebago Camper
 
Join Date: Dec 2018
Location: NC
Posts: 26
Quote:
Originally Posted by Goodspike View Post
I'n not seeing why low voltage would be necessarily poor wiring as opposed to too much demand. I agree they could be different voltages. Interesting you mention this. I was reading the instructions on the 50 amp Hughes EPO unit and it checks for more wiring errors than the 30 amp unit.

It checks for neutral reversed on both legs, but also for a neutral missing. I assume the 30 amp connected by a 50 to 30 dog bone would catch any relevant wiring errors, but I'm still thinking that through.

Edit: Thinking about it further about the only thing I can see is the 50 could be wired incorrectly and the 30 correctly, or visa versa, so it should be tested whichever you connect to.
Testing is a good idea for both types of service but the 50amp has a higher potential for a serious condition, one that can and has caused fires.
eldermike is offline   Reply With Quote
Old 03-17-2020, 04:38 PM   #64
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Here's something that might work--just add plugs. I wonder how you could effectively test the load the thing trips at?

https://www.amazon.com/30-Amp-Inline.../dp/B07QPR94J7

And here's another one that is ridiculously cheap where you would need to change both plugs. Also not sure of the amperage rating. It's so cheap I'd be afraid of it.

https://www.northerntool.com/shop/to...B&gclsrc=aw.ds
Goodspike is offline   Reply With Quote
Old 03-17-2020, 04:59 PM   #65
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
I found this from another site. Apparently we all have a label near our power inlet which says:

Quote:
(D) Labeling at Electrical Entrance. Each recreational vehicle
shall have a safety label with the signal word WARNING in
minimum 6-mm (1
∕4-in.) high letters and body text in minimum
3-mm (1
∕8-in.) high letters on a contrasting background. The
safety label shall be affixed to the exterior skin, at or near the
point of entrance of the power-supply cord(s), and shall read,
using one of the following warnings, as appropriate:
WARNING
THIS CONNECTION IS FOR 110–125-VOLT AC,
60 HZ, ____ AMPERE SUPPLY.
or
THIS CONNECTION IS FOR 208Y/120-VOLT or 120/240-
VOLT AC, 3-POLE, 4-WIRE,
60 HZ, ______ AMPERE SUPPLY.
DO NOT EXCEED CIRCUIT RATING.
EXCEEDING THE CIRCUIT RATING MAY CAUSE A
FIRE AND RESULT IN DEATH OR SERIOUS INJURY.
The correct ampere rating shall be marked in the blank
space.
page 70-467 of this rendition of the electrical code.

https://www.tooltexas.org/wp-content...NEC-Code-2.pdf
Goodspike is offline   Reply With Quote
Old 03-18-2020, 02:22 PM   #66
Winnebago Owner
 
youracman's Avatar
 
Join Date: Sep 2011
Location: Denver, CO
Posts: 73
Quote:
Originally Posted by Goodspike View Post
Here's something that might work--just add plugs. I wonder how you could effectively test the load the thing trips at?

https://www.amazon.com/30-Amp-Inline.../dp/B07QPR94J7

And here's another one that is ridiculously cheap where you would need to change both plugs. Also not sure of the amperage rating. It's so cheap I'd be afraid of it.

https://www.northerntool.com/shop/to...B&gclsrc=aw.ds

After I "melted" my 30A plug (for the 2nd time) I started using my adapter and the 50A service when available at RV parks. It just seems like the 50A receptacles at the pedestal are less "worn/loose" at the older parks. Now I'm gonna add one more item to the "stuff" at the pedestal ...... the inline ckt brkr from the Amazon link in your post. Didn't know they existed. Thanks for posting, Goodspike. (Like I was running out of things to do this winter! lol)

Good times and safe travels to ya.
__________________
Ed Sievers, Denver, CO
07 WGO 31ft Class C; Toad: '16 Soul with 6-spd DIY
"Be the person you needed when you were younger"
youracman is offline   Reply With Quote
Old 03-18-2020, 02:32 PM   #67
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by youracman View Post
Thanks for posting, Goodspike. (Like I was running out of things to do this winter! lol)

Good times and safe travels to ya.
You're welcome, but part of the reason I looked into this so much was the lack of things to do due to Covid-19. Glad to hear you're managing to stay busy.

FWIW, I bought one of those too.
Goodspike is offline   Reply With Quote
Old 03-18-2020, 04:05 PM   #68
Winnebago Owner
 
Join Date: Sep 2006
Posts: 109
Note in that Amazon link above -> referring to an inline 30A circuit breaker with two pigtails coming out each side with no plugs or receptacles on the ends of the pigtails - that the product description of it down below the picture talks mostly about the company that offers it being able to build custom interface cables.

I'd recommend contacting that company before you order anything: Ask them to build one for you with the 30A breaker inline with ... a short pigtail of 50A rated cable coming out one side with a RV pedestal 50A plug on it ... and a short pigtail of 30A rated cable coming out the other side with a 30A receptacle on it to accept the 30A cable plug coming from your RV's shore cable.

Order the above from them all ready to use -> and hopefully quailty-constructed by folks who know what they're doing and who are fully aware of UL Certification-type requirements.
Phil G. is offline   Reply With Quote
Old 03-18-2020, 04:23 PM   #69
Winnebago Owner
 
youracman's Avatar
 
Join Date: Sep 2011
Location: Denver, CO
Posts: 73
Quote:
Originally Posted by Phil G. View Post
Note in that Amazon link above -> referring to an inline 30A circuit breaker with two pigtails coming out each side with no plugs or receptacles on the ends of the pigtails - that the product description of it down below the picture talks mostly about the company that offers it being able to build custom interface cables.

I'd recommend contacting that company before you order anything: Ask them to build one for you with the 30A breaker inline with ... a short pigtail of 50A rated cable coming out one side with a RV pedestal 50A plug on it ... and a short pigtail of 30A rated cable coming out the other side with a 30A receptacle on it to accept the 30A cable plug coming from your RV's shore cable.

Order the above from them all ready to use -> and hopefully quailty-constructed by folks who know what they're doing and who are fully aware of UL Certification-type requirements.
Good point, Phil. Wiring new plugs at the end of my power cable (replacements for the melted ones) was not a real "fun" task. I "think" I did a good job ................... but it ain't factory, for sure. I considered just ordering a whole new power cable so as to have a molded plug on the end, but the J-box in my rig was installed by super sadists, I am fairly certain. :^) Really tough access .... and I am 88.

Best, Ed S.
__________________
Ed Sievers, Denver, CO
07 WGO 31ft Class C; Toad: '16 Soul with 6-spd DIY
"Be the person you needed when you were younger"
youracman is offline   Reply With Quote
Old 03-18-2020, 05:05 PM   #70
Winnebago Owner
 
Join Date: Feb 2017
Posts: 62
I'm not sure why I read this whole thread but I did.
We have 50 amp power and some campgrounds have two sites sharing the same power, one 30 amp and one 50 amp. First come, first served.
Twice in the last 130000 miles I've been assigned a site that the other camper had a 30 amp service and dogboned into the 50 amp service.
Well, now I know why!!
__________________
2003 Journey DL Whidbey Island USA
dickb46 is offline   Reply With Quote
Old 03-18-2020, 05:50 PM   #71
Winnebago Owner
 
Join Date: Sep 2006
Posts: 109
Quote:
Originally Posted by youracman View Post
Good point, Phil. Wiring new plugs at the end of my power cable (replacements for the melted ones) was not a real "fun" task. I "think" I did a good job ................... but it ain't factory, for sure. I considered just ordering a whole new power cable so as to have a molded plug on the end, but the J-box in my rig was installed by super sadists, I am fairly certain. :^) Really tough access .... and I am 88.

Best, Ed S.
Ed ... glad I could be of some help.

P.S. 88 ... Wow! I sure hope I can still be RV'ing someway, somehow, when/if I reach that number. I'm 77 but did still manage to get through today's 3X-per-week exercises a few hours ago ... but uugggggh it's tough to get through them.
Phil G. is offline   Reply With Quote
Old 03-18-2020, 07:01 PM   #72
Winnebago Camper
 
Join Date: Dec 2013
Posts: 41
No difference.
09 harley is offline   Reply With Quote
Old 03-18-2020, 07:13 PM   #73
Winnebago Master
 
Join Date: Nov 2005
Posts: 1,173
A lost of stuff here however basically using the 50 amp dogbone to run a 30 amp coach can be more reliable because as they age and get used the 30 amp breaker and receptacle on the post will start to wear and loose capacity while the 50 amp breaker and receptacle even after they start to degrade will more often be able to provide the full 30 amps service that you need.

I have received on a number of occasions a Low Voltage Warning on the 30 amp socket however found that often the 50 amp socket with the dogbone in those situations did not trigger the low voltage warning, etc.

Anyways campground pedestal 30 amp breakers left out in the weather (the covers with the openings for plugging in really do not protect 100% from the weather) and being regularly switched on and off, do not always provide a full 30 amp service and are known for degrading over time.
__________________
Neil V
2001 Winnebago Adventurer WFG35U
NeilV is offline   Reply With Quote
Old 03-18-2020, 09:30 PM   #74
Lee & Sandy DeFord
 
Join Date: Nov 2019
Location: Billings, Montana
Posts: 4
I am a 40 year electrician {IBEW Local 532} The 30 amp breaker is sized to protect the 30 amp wire used in smaller campers. There is usually another 30 amp main disconnect in the camper but this is not guaranteed. {Cheap guano from china and a loosley regulated industry} You need to check. It is allways better to connect a 30 amp cord to the 30 amp outlet. Doing otherwise creates a fire risk though one in the circuit in the camper will provide protection. I have seen many Breakers fail to trip at their current rating. {Even new ones. only a few out of a hundred are tested by the manufacturer.}

Reliability is a function of the quality of the breakers not the size. If you dont have one in your camper i suggest an inline breaker or fuse of 30 amps Slow blow {inrush current} before you connect to a 50 amp breaker. Many campgrounds have old unreliable breakers. Better to rely on your own equipment for circuit protection. Personally i like the Q series of Square D.
Sandy D. is offline   Reply With Quote
Old 03-18-2020, 09:47 PM   #75
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by NeilV View Post
I have received on a number of occasions a Low Voltage Warning on the 30 amp socket however found that often the 50 amp socket with the dogbone in those situations did not trigger the low voltage warning, etc.
That's most likely because the dog bone was pulling off a different leg of the service than the 30 amp was wired to. A dog bone has to be wired to one or the other. To make matters worse, it's even possible the electrician wiring the place wired all the 30 amps into the same leg, and that would affect both people using the 30 and people really using the 50 (non-dog bone). Stated differently, it's likely that if you'd measured the voltage of both sides of the 50 amp service that one would have equaled the 30. And a differently wired dog bone would have had the same low voltage.
Goodspike is offline   Reply With Quote
Old 03-19-2020, 08:06 AM   #76
Winnebago Master
 
powercat_ras's Avatar
 
Join Date: May 2015
Location: Manhattan, Kansas USA
Posts: 758
You can get a 50A plug to two 30A socket adapter. One 30A socket is off 50A phase 1 and other is off 50A phase 2. You can read AC volts on each socket and plug your 30A into the socket has better power, if there's a difference. They sell for under $ 40.
__________________
Randy - Manhattan, Kansas
2015 Vista 27N
2016 Honda HR-V
powercat_ras is offline   Reply With Quote
Old 03-19-2020, 08:54 AM   #77
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by powercat_ras View Post
You can get a 50A plug to two 30A socket adapter. One 30A socket is off 50A phase 1 and other is off 50A phase 2. You can read AC volts on each socket and plug your 30A into the socket has better power, if there's a difference. They sell for under $ 40.
Not a bad idea, but at some point you get into the number of connections issue. Although really at only 30 amps off of 50 amp connections I'm not sure how big of an issue that is. And if you're not running AC it's probably not an issue at all.
Goodspike is offline   Reply With Quote
Old 03-19-2020, 09:01 AM   #78
Winnebago Camper
 
Join Date: Dec 2018
Location: NC
Posts: 26


I am a design engineer with 45 years experience in designing and bringing to market circuit breakers for DC power systems. I have several patents on circuits and actual breakers. I am retired now but consult on battery management system design for mass transit buses and helping to bring to market a new design that might one day be useful even in the RV industry if the cost can be brought down.

With that all said. I am afraid of power pedestals in campgrounds. I check them carefully before I plug in. I have found voltage differences many times and many times I have waited until the pedestal was opened and checked before I plugged in. I use a progressive industries surge protector and read the lights before I plug in. If the plugs look old or broken I check them with a meter. I check neutral to ground as my most important test. there should be zero reading from neutral to ground. A floating neutral will create a voltage difference between L1 and L2 under load. Notice I said under load. Testing without a load is a fools test but we have no choice because the actual load test will be our RV's. On 50 amp service a lose neutral could result in a voltage spike on L1 or L2, who knows which? So once plugged in I have a panel meter that shows me voltage on each leg. I accept some voltage drop on legs when the AC is running or some other load. But I will not accept any voltage increase based on any load.

Suggestion: Learn how this split phase power system works before you look for ways to improve your power. Understand your RV is not grounded, it's floating with your ground running through a plug and back to ground by connections inside the pedestal.
If you have a 30amp cord set plugged into a 50amp breaker make sure you have a working 30 amp main breaker inside the RV. The wire you are plugging in is not rated for 50 amps and it will fail at the connection points on one end or the other if it's overloaded for an extended period. As I posted before I don't like plugs they are poor connections but necessary ones. Plugs into plugs is just adding voltage drop and potential unplanned thermal events.

I enjoy this forum.
eldermike is offline   Reply With Quote
Old 03-19-2020, 09:22 AM   #79
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by eldermike View Post
Understand your RV is not grounded, it's floating with your ground running through a plug and back to ground by connections inside the pedestal.
Excellent point.

Quote:
If you have a 30amp cord set plugged into a 50amp breaker make sure you have a working 30 amp main breaker inside the RV.
That is also an excellent point. I haven't been to my RV since I thought about that. I'm pretty sure mine doesn't have a main breaker, but that's just from recollection. I seem to recall that NEC link I posted above didn't require it, but I was looking for something else at the time and haven't gone back to look.
Goodspike is offline   Reply With Quote
Old 03-19-2020, 09:42 AM   #80
Winnie-Wise
 
Join Date: Jan 2020
Posts: 291
Quote:
Originally Posted by eldermike View Post
Wow, that is good, although I'm not sure of the explanation at the end. But I can understand why that would be a huge issue given different circuits often share a common neutral on the way back to the breaker box. I'll pay more attention when I see open neutral in the future.

One other thing from that video. He said they try to design the house system to balance the loads between the legs. My comment earlier today was suggesting that whoever installed an RV park system might not have tried to balance the loads of the 30 amp circuits. I could see someone might have even put all the 30s on one leg just to be consistent in what they did.
Goodspike 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
I Got More Cooling & Better Heat From My Basement AC Doing This! imnprsd Electrical | Charging, Solar and Electronics 14 10-29-2019 02:19 AM
For Sale: 2007 Winnebago Vista 30b Solar & Many More Upgrades jimgior RV's and Tow Vehicles For Sale & Wanted 0 01-05-2019 08:14 PM
Full wall slide reliable? Mortgagehomes General Maintenance and Repair 7 07-26-2010 09:40 PM
Reliable Winny dealer needed wagonmaster2 Winnebago General Discussions 6 03-10-2010 09:38 PM
More confusion than ever about DTV converter box, with one more question GG1 Electrical | Charging, Solar and Electronics 81 10-16-2008 06:21 PM

» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Winnebago Industries or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 05:59 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×