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

Go Back   Keystone RV Forums > Keystone Tech Forums > Technical Corner
Click Here to Login

Reply
 
Thread Tools Display Modes
 
Old 09-15-2022, 09:59 AM   #61
flybouy
Site Team
 
Join Date: Oct 2011
Location: Joppa, MD
Posts: 10,780
Quote:
Originally Posted by Shedboy View Post
Auto-former won't do the job -


1. Autoformer output varies proportionally to input, as the input voltage varies, so does the output voltage. If the autoformer is set up when the line voltage is low a sudden rise in line voltage (all the other RVs leave the park) the autoformer will amplify the increased voltage to the remaining RV, an undesirable situation.

This incorrect, it will not overvoltage. If the line voltage is withing the paramaters it will simply pass it thru.

There may be some other name rather than "autoformer" for an ACTIVE device (a device that consumes energy) that would keep the output voltage constant but the energy (WATTS) in the system remains constant, (law of conservation of energy) e.i. the current (amps) would decrease.
Autoformer is a brand name.. The devicce is simply a boost transformer.
Off into the weeds - keep in mind that in AC circuits there is a forth attribute, POWER FACTOR, that is in play. Unlikely in this case but again, nothing can be done at the RV space other than alternative power source.

2. Correct Ohms Law for current is Amps (current) = Watts (power) / (divided by) E (voltage), I=W/E Ohms Law is a simple mathematical equation that can be written in several variants using middle school algebra. I try to keep things simple when your reader isn'tfamiliar with the subject.
3. Because the deficiency occurs for multiple RV spaces, the problem is likely to be upstream of any one RV pedestal.
4. Because the Park technician can't wait for the season to be over to repair the problem indicates the problem is in-between the utility company power lines and the pedestals (RV Park electrical distribution panels or possible ground loop). Nothing can repair the problem at the RV space other than employing an alternative power source - generator, solar panels or wind turbine.
5. Beware of a potential (unlikely) safety issue, the possibility of a ground loop condition associated with the neutral (green) wire. The neutral wire is always white. The ground is green on an insulated wire or bare wire on a solid wire installation. Measure the AC voltage between the RV frame and the pedestal metal utility box. It should be zero. A remedy to this possible condition would be to ground the RV frame to a metal RV Park water pipe using a battery jumper cable. This condition is unlikely because the problem seems to be associated with several RV spaces. Again, the problem seems to be upstream of the pedestals.
See my comments in red for some clarifications.
__________________
Marshall
2012 Laredo 303 TG
2010 F250 LT Super Cab, long bed, 4X4, 6.4 Turbo Diesel
flybouy is offline   Reply With Quote
Old 09-15-2022, 11:42 AM   #62
Shedboy
Member
 
Join Date: Oct 2020
Location: Colorado Springs
Posts: 30
Re: Autoformer:

Sorry for the confusion between Autoformer and Autotransformer,

Note the following:



1. Neither is a brand name.
2. As indicated "autoformer" is an active device (dissipates energy) and consists of several electrical components.

3. In this universe, the law of conservation of energy is unbroken.
4. The energy output of a closed system (autoformer) will ALWAYS be less that the input, exacerbating the RV Pedestal issue, not improving it.
5. The "auto" (Greek for "self") prefix refers to a single coil acting alone, not to any kind of automatic mechanism. (The nomenclature is self-contradictory, "auto" excludes all but one electrical component).

Autotransformer:

From Wikipedia, the free encyclopedia










Single-phase tapped autotransformer with an output voltage range of 40%–115% of input


An autotransformer is an electrical transformer with only one winding. The "auto" (Greek for "self") prefix refers to the single coil acting alone, not to any kind of automatic mechanism. In an autotransformer, portions of the same winding act as both the primary winding and secondary winding sides of the transformer. In contrast, an ordinary transformer has separate primary and secondary windings which have no metallic conducting path between them.
The autotransformer winding has at least three taps where electrical connections are made. Since part of the winding does "double duty", autotransformers have the advantages of often being smaller, lighter, and cheaper than typical dual-winding transformers, but the disadvantage of not providing electrical isolation between primary and secondary circuits. Other advantages of autotransformers include lower leakage reactance, lower losses, lower excitation current, and increased VA rating for a given size and mass.[1]





OHMS LAW:
1. A prior member posting misstated Ohms Law as


"OHM's law states a very simple equation. Amps=Vonts x Watts"


This is incorrect, I posted a graceful correction for this misstatement.
Technically, for this situation, the correct and simple equation is Amps = watts/impedance (I=P/Z).





2. The neutral wire is always white


Correct! or it is supposed to be always white. The ground loop defect condition referred to could include the white wire, the bare wire or the green wire (if there is one), all are subject to a ground loop conditions. A reversed white and green may cause a ground loop. However, since multiple pedestals are effected, any ground loop condition is probably upstream of the pedestals, possibly no earth ground at the distribution point? If the white wire is broken, the bare wire is trying to do the work, a dangerous condition.



Above assumes that the pedestals are a 4 wire system, not antiquated 3 wire system. Does each pedestal have its own earth ground? In either case, grounding the RV frame to an earth ground is a good safety practice if something isn't right the occupants are thereby protected. Stepping from an RV steel stair step onto the wet dirt can be an electrifying experience.
Shedboy is offline   Reply With Quote
Old 09-15-2022, 11:50 AM   #63
hawghauler
Senior Member
 
hawghauler's Avatar
 
Join Date: Apr 2022
Location: Middletown PA
Posts: 133
My on an 5500 burns 10 gallons of gasoline in a 25 HR period
If I paid for full hookups I'd expect a reimbrsement for fuel and wear and tear on my equipment
hawghauler is offline   Reply With Quote
Old 09-15-2022, 11:58 AM   #64
Shedboy
Member
 
Join Date: Oct 2020
Location: Colorado Springs
Posts: 30
Re Ohms LAw ;


The correct equation is
This is incorrect, I posted a graceful correction for this misstatement.
Technically, for this situation, the correct and simple equation is Amps = watts/impedance (I=P/Z).


CORRECTION Amps = sqr root (watts divided by impedance)



ignoring power factor
Shedboy is offline   Reply With Quote
Old 09-15-2022, 01:20 PM   #65
wiredgeorge
Senior Member
 
wiredgeorge's Avatar
 
Join Date: Nov 2017
Location: Mico, TX
Posts: 5,848
Am I going to have to pay for this education? I thought formula was what you used to be able to give to a baby but the country kinda ran out?
__________________
wiredgeorge Mico TX
2006 F350 CC 4WD 6.0L
2002 Keystone Cougar 278
2006 GL1800 Roadsmith Trike
wiredgeorge is offline   Reply With Quote
Old 09-15-2022, 02:03 PM   #66
Shedboy
Member
 
Join Date: Oct 2020
Location: Colorado Springs
Posts: 30
Reminisce Simpler Times

Yea - I still have a table lamp with 2 conductor cloth covered twisted pair wires and a 2 prong plug that will fit into a receptacle in either direction. Seems like RV's could benefit from an advancement in simplicity like "plug n play". (Trigonometry not required.)
Shedboy is offline   Reply With Quote
Old 09-15-2022, 02:39 PM   #67
sourdough
Site Team
 
Join Date: Feb 2014
Location: W. Texas
Posts: 15,512
Quote:
Originally Posted by Shedboy View Post
Re: Autoformer:

Sorry for the confusion between Autoformer and Autotransformer,

Note the following:



1. Neither is a brand name.

Just an fyi:

https://hughesautoformers.com/product/pwd50-epo/

Note upper left corner of website.
__________________
Danny & Susan wife of 55 years
2019 Ram 3500 Laramie CC SB 6.4 4x4 4.10
2020 Montana High Country 331RL
sourdough is offline   Reply With Quote
Old 09-15-2022, 03:28 PM   #68
wiredgeorge
Senior Member
 
wiredgeorge's Avatar
 
Join Date: Nov 2017
Location: Mico, TX
Posts: 5,848
Quote:
Originally Posted by sourdough View Post
Just an fyi:

https://hughesautoformers.com/product/pwd50-epo/

Note upper left corner of website.
What are you trying to point out for those of us that see nothing worth noting? They have a menu bar and pictures of their gizmo below.
__________________
wiredgeorge Mico TX
2006 F350 CC 4WD 6.0L
2002 Keystone Cougar 278
2006 GL1800 Roadsmith Trike
wiredgeorge is offline   Reply With Quote
Old 09-15-2022, 03:30 PM   #69
sourdough
Site Team
 
Join Date: Feb 2014
Location: W. Texas
Posts: 15,512
Quote:
Originally Posted by wiredgeorge View Post
What are you trying to point out for those of us that see nothing worth noting? They have a menu bar and pictures of their gizmo below.

I just noted that "Hughes AUTOFORMERS" is a brand name.
__________________
Danny & Susan wife of 55 years
2019 Ram 3500 Laramie CC SB 6.4 4x4 4.10
2020 Montana High Country 331RL
sourdough is offline   Reply With Quote
Old 09-15-2022, 03:48 PM   #70
Shedboy
Member
 
Join Date: Oct 2020
Location: Colorado Springs
Posts: 30
Brand Name?

Here are the top three most popular and well-rated autoformer brands that deliver a consistent and top-notch quality result. There are only a few of them, so picking the right one is essential.
  • Hughes Autoformers – founded by an RV enthusiast in 1995. Hughes, the founder, also experienced himself the low voltage and even fluctuating supply that can be provided by RV campsites. He also had to deal with damaged electrical devices, so he created his autotransformer, which eventually also helped thousands of other RVers. The results of his highly reliable autoformers are results of his first-hand experiences.
  • Southwire – this company has a wide array of electrical connections and devices used for transmission. They have various cords and connectors, including voltage regulators.
  • InnoTechRV – their single autoformer, the Power Master VC-50, is worth checking. It is a reliable combo of an auto-transformer and a surge protector"
Note:



1. Multiple manufacturers define their product as "autoformers". Hughs uses the terms "autoformer" and "autotransformer" interchangeably for the same product, technically incorrect, or is it?. No manufacturer designates either term with a copywrite symbol that indicates a BRAND or copywrite name.


2. More germane to the issue is the lack of mention of Ground Fault Interrupters (GFI). All modern RV pedestals have GFI's and ganged GFI's are used somewhere on the 220VAC distribution. One contributor explained how modern circuit breakers work, GFI's work on the ground/neutral wires. I'll bet that there isn't a GFI on the park grounds.
Shedboy is offline   Reply With Quote
Old 09-16-2022, 04:47 AM   #71
flybouy
Site Team
 
Join Date: Oct 2011
Location: Joppa, MD
Posts: 10,780
I sure hope this helped clear up the OP's issue. This de-railement went over a bridge into a canyon.
__________________
Marshall
2012 Laredo 303 TG
2010 F250 LT Super Cab, long bed, 4X4, 6.4 Turbo Diesel
flybouy is offline   Reply With Quote
Old 09-16-2022, 05:13 AM   #72
jasin1
Senior Member
 
jasin1's Avatar
 
Join Date: Aug 2020
Location: Upper Chesapeake Bay
Posts: 3,879
Quote:
Originally Posted by flybouy View Post
I sure hope this helped clear up the OP's issue. This de-railement went over a bridge into a canyon.
i’d suggest the op print out this thread in its entirety and show it to the campground manager….that should help to explain his problem
__________________
2020 Cougar 315 RLS
2020 Ram 3500 6.7HO 4.10 Dually Aisin
jasin1 is offline   Reply With Quote
Old 09-16-2022, 06:29 AM   #73
JRTJH
Site Team
 
JRTJH's Avatar
 
Join Date: Mar 2011
Location: Gaylord
Posts: 24,560
Quote:
Originally Posted by jasin1 View Post
i’d suggest the op print out this thread in its entirety and show it to the campground manager….that should help to explain his problem
And, if it doesn't, with all the "pages and pages of fodder" he can use the paper to start a campfire to have some light around the trailer until his generator recharges his battery and he can turn the lights back on......
__________________
John



2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS
JRTJH is offline   Reply With Quote
Old 09-22-2022, 01:08 PM   #74
Life-in-Him
Senior Member
 
Life-in-Him's Avatar
 
Join Date: Jun 2020
Location: Box Elder
Posts: 137
Quote:
Originally Posted by hlh1 View Post
For Giggles I tested the line again at 27 amps and received 108 volts ac.
Edit:
After entering the comments below agter comment #54, I see others posted similar comments & the OP said there was no 15/20 socket. Oh well, I guess age developes impatience or patience galore
Temp, or socket condition still stand.
We also use a Hughes Autoformer (30 amp) & a Hughes Power Watchdog which do control the input voltage & max current well.

Out of curiosity, have you measured the voltage on the pedestal 15/20 amp outlet under the same conditions showing that 108V?
Also do you have a digital thermometer? Does it read the socket or part of it higher than the socket mount?
Was the socket discolored when you plugged in?

All of these are signs of pedestal &/or maintenance issues.
Life-in-Him is offline   Reply With Quote
Old 09-26-2022, 11:51 AM   #75
Shedboy
Member
 
Join Date: Oct 2020
Location: Colorado Springs
Posts: 30
For Giggles Sequel

Agree w Flybouy - This is a shot-in-the-dark but the situation is potentially dangerous.



Many aerial power line neutral wires are coaxial, they have an aluminum center conductor inside of a braided steel sheath. The aluminum carries the electricity and the steel carries the physical weight of the cable. The neutral wire will always have current flowing while the branch wires will have discontinuous or variable current flow.



In beachfront areas the salt-air continuously bathes the aerial power lines feeding the facility. After many years the galvanic action between the steel and aluminum, enhanced by the salt (sodium chloride), will corrode the aluminum until nothing is left but the steel braid. The neutral wire will dissolve before the others because it is carrying electricity continuously.



The result is the conditions that you describe, called an unbalanced line, where all of the pedestals will be affected, some with higher voltage and some with lower voltage depending on which side of the remaining power line is feeding them, how many RV's are connected and the integrity of the RV's earth ground that is now carrying the electricity normally carried by the missing aluminum core wire via the pedestal white wire.



This is a dangerous condition. Sometimes the power line aluminum core wire is completely gone and only the remaining rusted steel braid remains, this condition is visible from the ground, you can see through the steel braid. Keep your RV tied to an earth ground!
Shedboy is offline   Reply With Quote
Reply

Tags
power

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
Forum Jump

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by the Keystone RV Company or any of its affiliates in any way. Keystone RV® is a registered trademark of the Keystone RV Company.


All times are GMT -8. The time now is 01:00 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.