Good Sam Club Open Roads Forum: Please confirm what I think I already know
Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Please confirm what I think I already know

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 6  
Prev  |  Next
barchetta1

SC

Full Member

Joined: 09/11/2016

View Profile


Offline
Posted: 06/19/19 12:25pm Link  |  Quote  |  Print  |  Notify Moderator

pianotuna wrote:

Hi,

I use my autoformer a lot. My comfort zone is 107 volts and up. Strictly speaking, an autoformer is not an isolation device. It is a single wind transformer with more than one tap. In my case, it has 3 layers of boost (110, 100, 90) and one of buck (135).

The Sola Basic is "fast enough" to boost in less than 1/3 of a second when the roof air cycles on.

Thanks to Mex it has state of the art surge protection.

Here is a link that may assist you by comparing cost of electric vs propane:

http://www.maxmcarter.com/fuels/fuelscalc.html

I do have a modest solar panel system.


sorry I missed this post and stand corrected.. I assumed it was an isolation transformer.. come to think about it, that transformer would have to be ginormous isolate 30 amps.

I guess my dilemma as I mentioned earlier is do I spend the money on a 30 amp surge suppressor or one with v regulation built-in.

thanks for the link, headed there tonight!

I assume your solar panel setup is for when you have no shore power. I do have a panel with a modest 12v battery built in. But thats only really good enough for a charge of my cell phone and maybe part of my laptop. its made for hunting camera's.

I cant decide on the autoformer.. on the one had if my ac goes out I will wonder if voltage did it and beat myself up, on the other Im currently paying a premium for a premium campground that is safe and offers good utils and clean grounds with a no idiots tenant policy. One complaint and you are out.

Is this the Sola you have?

[image]
[image]

* This post was edited 06/19/19 12:39pm by barchetta1 *

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile





Offline
Posted: 06/19/19 02:20pm Link  |  Quote  |  Print  |  Notify Moderator

As I said in my previous post which you must have missed:

You cannot use more than 24 amps on a 30 amp feed for any length of time. You simply can't get away with it. The 30 amp breaker in the pedestal or your main feed should trip if they're doing their jobs.

Beyond them tripping, your cord connectors will have heated up at that point and sooner or later, you'll blacken the blades and melt the cord caps and ruin the socket on the pedestal.

YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.

The more boost your autoformer provides, the more amps that will be drawn. You can't get more than 24 amps for any length of time! Bypassing the 30 amp RV breaker by adding a 20 amp breaker is only going to ensure the pedestal breaker trips.


Don Ford
2004 Safari Trek 31SBD (F53/V10 20,500GVW)
'09 HHR 2LT or '97 Aerostar MiniVan (Remco driveshaft disconnect) for Towed vehicles
BlueOx Aventa II Towbar - ReadyBrake Inertia Brake System


barchetta1

SC

Full Member

Joined: 09/11/2016

View Profile


Offline
Posted: 06/19/19 02:46pm Link  |  Quote  |  Print  |  Notify Moderator

DFord wrote:

As I said in my previous post which you must have missed:

You cannot use more than 24 amps on a 30 amp feed for any length of time. You simply can't get away with it. The 30 amp breaker in the pedestal or your main feed should trip if they're doing their jobs.

Beyond them tripping, your cord connectors will have heated up at that point and sooner or later, you'll blacken the blades and melt the cord caps and ruin the socket on the pedestal.

YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.

The more boost your autoformer provides, the more amps that will be drawn. You can't get more than 24 amps for any length of time! Bypassing the 30 amp RV breaker by adding a 20 amp breaker is only going to ensure the pedestal breaker trips.


It would seem you misread my posts or I wasnt clear. Either way sorry you are so upset.

Bumpyroad

Virginia

Senior Member

Joined: 12/01/2005

View Profile


Offline
Posted: 06/19/19 04:12pm Link  |  Quote  |  Print  |  Notify Moderator

barchetta1 wrote:

Bumpyroad wrote:

Yesterday was running air, water heater and micro. 30amp main blew.

of course it did.
bumpy


Why do you say of course? RV should be designed for full load? Are you being sarcastic? Sorry can't tell.
.


to quote a post
"YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.
bumpy





barchetta1

SC

Full Member

Joined: 09/11/2016

View Profile


Offline
Posted: 06/19/19 04:15pm Link  |  Quote  |  Print  |  Notify Moderator

Bumpyroad wrote:

barchetta1 wrote:

Bumpyroad wrote:

Yesterday was running air, water heater and micro. 30amp main blew.

of course it did.
bumpy


Why do you say of course? RV should be designed for full load? Are you being sarcastic? Sorry can't tell.
.


to quote a post
"YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.
bumpy


Again, sorry you are so upset. Have a great day.

Gdetrailer

PA

Senior Member

Joined: 01/05/2007

View Profile



Posted: 06/19/19 05:04pm Link  |  Quote  |  Print  |  Notify Moderator

DFord wrote:

As I said in my previous post which you must have missed:

You cannot use more than 24 amps on a 30 amp feed for any length of time. You simply can't get away with it. The 30 amp breaker in the pedestal or your main feed should trip if they're doing their jobs.

Beyond them tripping, your cord connectors will have heated up at that point and sooner or later, you'll blacken the blades and melt the cord caps and ruin the socket on the pedestal.

YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.

The more boost your autoformer provides, the more amps that will be drawn. You can't get more than 24 amps for any length of time! Bypassing the 30 amp RV breaker by adding a 20 amp breaker is only going to ensure the pedestal breaker trips.


Wrong on many levels.

First of all, you CAN "use" ALL 30A of a 30A circuit breaker, the trick is it is for a SHORT TIME. You conveniently omitted the TIME FACTOR.

Circuit breakers are rated at 80% on a "continuous" basis and continuous in the electrical world is a circuit loaded to capacity for 3 hrs or more.

In reality, a 30A breaker must be able to sustain a 100% RATING INDEFINITELY, HOWEVER, NEC dictates 80% FOR APPLICATION!

Why the difference?

HEAT, yep, heating of the circuit (wires, switches, breakers) comes into play.

Heating takes TIME, so in reality, it IS possible to run a 30A load for a SHORT TIME on a 30A circuit without tripping the breaker.

OP must have a single pole "combo" breaker with 30A AND 20A breakers, combo breakers tend to false trip if both circuits on the SAME breaker are heavily loaded for LONG periods of time.

The fix for that is to use full size SINGLE CIRCUIT breakers or if box accepts two SEPARATE 1/2 size breakers or if that is not possible MOVE a lesser amperage circuit to the combo breaker (IE, change 30A/20A single to a 30A/15A single then move a 15A circuit to that breaker).

I am not a fan of those combo breakers but sometimes you do not have a choice and I have used them in those cases.

HERE is a good "primer" on CB sizing..

You do make a good point, the OP DOES need to learn to "manage" HEAVY loads. OP must learn to manually shed loads when a lot of heavy loads are needing to be used at one time.

As far as those "autoformers" goes, yes, you could use one, however due to power loses you basically are trading off one issue for another.

A 30A 120V RV gets you a max of 3600W to work with, using an autoformer to BOOST low INPUT voltage from the campground will result in a slight loss of available USABLE wattage so in reality you might only get say maybe 3400W (28A) in your RV and start tripping the campgrounds 30A breaker depending on how much the autoformer has to boost the voltage.

Power management will be critical, sometimes difficult to get used to if you are coming from a 100A or higher 240/120 service entrance life of a real home.

Personally, before dumping tons of money down the drain for an autoformer, perhaps take a hard look at what you feel are fragile..

Most electrical devices ARE designed to operate as low as 108V and not sustain damage.. If you are in a campground that is continually having brownouts of 107V or lower then it is time to MOVE ON..

Campgrounds I have been in the lowest voltage I have seen on my monitor has been 111V with an average of 119V in the summer in a park with 1800 campsites.. Heck I have seen worse voltages at a cousins home we visit in the summer time..

pianotuna

Regina, SK, Canada

Senior Member

Joined: 12/18/2004

View Profile


Offline
Posted: 06/19/19 05:50pm Link  |  Quote  |  Print  |  Notify Moderator

Hi,

Yes that is the same unit I own and love.

It is not often that 30 amps will power 3 heavy draw items.

Some of us get around that by having auxiliary shore power cords. I have the OEM 30, a 20, and a 15 amp. I use a patch board approach using plugs, so I can return the RV to OEM wiring in seconds.

I do have an inverter/charger that allows load support--so I can draw more than 30 amps for a while. BTW load support is NOT voltage support--hence I have the autoformer.

barchetta1 wrote:


sorry I missed this post and stand corrected.. I assumed it was an isolation transformer.. come to think about it, that transformer would have to be ginormous isolate 30 amps.

I guess my dilemma as I mentioned earlier is do I spend the money on a 30 amp surge suppressor or one with v regulation built-in.

thanks for the link, headed there tonight!

I assume your solar panel setup is for when you have no shore power. I do have a panel with a modest 12v battery built in. But thats only really good enough for a charge of my cell phone and maybe part of my laptop. its made for hunting camera's.

I cant decide on the autoformer.. on the one had if my ac goes out I will wonder if voltage did it and beat myself up, on the other Im currently paying a premium for a premium campground that is safe and offers good utils and clean grounds with a no idiots tenant policy. One complaint and you are out.

Is this the Sola you have?

[image]



Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp hours of AGM in two battery banks 12 volt batteries, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

CharlesinGA

South of Atlanta, Georgia

Senior Member

Joined: 01/12/2016

View Profile


Offline
Posted: 06/19/19 08:43pm Link  |  Quote  |  Print  |  Notify Moderator

barchetta1 wrote:

Bumpyroad wrote:

Yesterday was running air, water heater and micro. 30amp main blew.

of course it did.
bumpy


Why do you say of course? RV should be designed for full load? Are you being sarcastic? Sorry can't tell.

EDIT: if you read the review I posted I think this personal nailed it. In my coach the 30amp main and 20amp AC are combined into one breaker. the heat created likely causes the main to pop early since it is sitting on top and taking the heat from the AC.


NO, they are not designed for a full load. A microwave is 750 to 1000 watts. the A/C is 1500 to 1600 watts, the water heater is about 1400 watts, and the fridge, when running on AC current is an intermittent load of 500 watts or so. You also have a power converter using 120v AC to make 12v DC to charge the batteries and run the light. These can be drawing several hundred watts also.

Basically, you need to pick what you want to use, and turn off the rest. If running the AC, then its OK to run EITHER the water heater or the microwave, but NOT both. In fact my motorhome, now sold, had an automatic load switch that allowed the water heater to run, until it saw load on the microwave circuit, at which time it shut off power to the water heater. When the microwave stopped, it again turned on the water heater. KEEP stuff turned off if you are not using it. Water heats very quickly in the tiny water heaters RV's have, so don't leave it on, turn it on, let it heat, use it, shut if off.

30 amps at 120 volts is 3600 watts. National Electric Code considers anything running continuously and anything that generates heat, such as an electric water heater to be a continuous load. Your total continuous load should never exceed 80% of your total, thus anything over about 2900 watts is too much, and you will eventually burn up your power plug on the end of your shore cord, and also have other issues in the electric system.

Charles

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile





Offline
Posted: 06/19/19 10:46pm Link  |  Quote  |  Print  |  Notify Moderator

Gdetrailer wrote:

DFord wrote:

As I said in my previous post which you must have missed:

You cannot use more than 24 amps on a 30 amp feed for any length of time. You simply can't get away with it. The 30 amp breaker in the pedestal or your main feed should trip if they're doing their jobs.

Beyond them tripping, your cord connectors will have heated up at that point and sooner or later, you'll blacken the blades and melt the cord caps and ruin the socket on the pedestal.

YOU CANNOT USE 3 HIGH AMP APPLIANCES AT ONE TIME ON 30 AMPS WITHOUT BREAKERS TRIPPING OR YOUR CORD CONNECTERS HEATING UP AND MELTING THE CORD CAPS.

The more boost your autoformer provides, the more amps that will be drawn. You can't get more than 24 amps for any length of time! Bypassing the 30 amp RV breaker by adding a 20 amp breaker is only going to ensure the pedestal breaker trips.


Wrong on many levels.

First of all, you CAN "use" ALL 30A of a 30A circuit breaker, the trick is it is for a SHORT TIME. You conveniently omitted the TIME FACTOR.

Circuit breakers are rated at 80% on a "continuous" basis and continuous in the electrical world is a circuit loaded to capacity for 3 hrs or more.

In reality, a 30A breaker must be able to sustain a 100% RATING INDEFINITELY, HOWEVER, NEC dictates 80% FOR APPLICATION!

Why the difference?

HEAT, yep, heating of the circuit (wires, switches, breakers) comes into play.

Heating takes TIME, so in reality, it IS possible to run a 30A load for a SHORT TIME on a 30A circuit without tripping the breaker.

OP must have a single pole "combo" breaker with 30A AND 20A breakers, combo breakers tend to false trip if both circuits on the SAME breaker are heavily loaded for LONG periods of time.

The fix for that is to use full size SINGLE CIRCUIT breakers or if box accepts two SEPARATE 1/2 size breakers or if that is not possible MOVE a lesser amperage circuit to the combo breaker (IE, change 30A/20A single to a 30A/15A single then move a 15A circuit to that breaker).

I am not a fan of those combo breakers but sometimes you do not have a choice and I have used them in those cases.

HERE is a good "primer" on CB sizing..

You do make a good point, the OP DOES need to learn to "manage" HEAVY loads. OP must learn to manually shed loads when a lot of heavy loads are needing to be used at one time.

As far as those "autoformers" goes, yes, you could use one, however due to power loses you basically are trading off one issue for another.

A 30A 120V RV gets you a max of 3600W to work with, using an autoformer to BOOST low INPUT voltage from the campground will result in a slight loss of available USABLE wattage so in reality you might only get say maybe 3400W (28A) in your RV and start tripping the campgrounds 30A breaker depending on how much the autoformer has to boost the voltage.

Power management will be critical, sometimes difficult to get used to if you are coming from a 100A or higher 240/120 service entrance life of a real home.

Personally, before dumping tons of money down the drain for an autoformer, perhaps take a hard look at what you feel are fragile..

Most electrical devices ARE designed to operate as low as 108V and not sustain damage.. If you are in a campground that is continually having brownouts of 107V or lower then it is time to MOVE ON..

Campgrounds I have been in the lowest voltage I have seen on my monitor has been 111V with an average of 119V in the summer in a park with 1800 campsites.. Heck I have seen worse voltages at a cousins home we visit in the summer time..


Gdetrailer,

How does "FOR ANY LENGTH OF TIME" as I put it differ from the way you worded it - "SHORT TIME"? It makes me wonder how much of what I wrote you actually read. I said you can't use anymore than 24 amps for any length of time. You said breakers are rated at 80% for continuous use. (30 x 0.8 = 24) We're saying the same thing using different words. There's no reason to begin your comments with "WRONG ON MANY LEVELS" unless you're trying to be disingenuous. You just reiterated almost everything I said - perhaps in words more to your liking but still your attack on what I said was unnecessary.

I'd be willing to bet any campground that found someone plugged into both the 30 amp and 20 amp receptacles on their pedestals will be asked to pay 50 amp rate or leave the park.

barchetta1

SC

Full Member

Joined: 09/11/2016

View Profile


Offline
Posted: 06/20/19 02:59am Link  |  Quote  |  Print  |  Notify Moderator

pianotuna wrote:

Hi,

Yes that is the same unit I own and love.

It is not often that 30 amps will power 3 heavy draw items.

Some of us get around that by having auxiliary shore power cords. I have the OEM 30, a 20, and a 15 amp. I use a patch board approach using plugs, so I can return the RV to OEM wiring in seconds.

I do have an inverter/charger that allows load support--so I can draw more than 30 amps for a while. BTW load support is NOT voltage support--hence I have the autoformer.

barchetta1 wrote:


sorry I missed this post and stand corrected.. I assumed it was an isolation transformer.. come to think about it, that transformer would have to be ginormous isolate 30 amps.

I guess my dilemma as I mentioned earlier is do I spend the money on a 30 amp surge suppressor or one with v regulation built-in.

thanks for the link, headed there tonight!

I assume your solar panel setup is for when you have no shore power. I do have a panel with a modest 12v battery built in. But thats only really good enough for a charge of my cell phone and maybe part of my laptop. its made for hunting camera's.

I cant decide on the autoformer.. on the one had if my ac goes out I will wonder if voltage did it and beat myself up, on the other Im currently paying a premium for a premium campground that is safe and offers good utils and clean grounds with a no idiots tenant policy. One complaint and you are out.

Is this the Sola you have?

[image]



Well that is likely a less expensive way of getting an autoformer [emoticon]

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 6  
Prev  |  Next

Open Roads Forum  >  Tech Issues

 > Please confirm what I think I already know
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2019 CWI, Inc. © 2019 Good Sam Enterprises, LLC. All Rights Reserved. | Terms of Use | PRIVACY POLICY | YOUR PRIVACY RIGHTS