complaints when using a hughes autoformer

SoundGuy wrote:

Lantley wrote:
This weekend I had my autoformer in use however no one else seemed concerned about the low voltage. Without an EMS or at least a meter I imagine they were not aware the low voltage condition existed.
As the saying goes "Ignorance is bliss"

Totally unscientific but I'd bet that describes 99.9% of RVrs. :R Of the many friends and others we know who camp I can't think of a single one who owns an autoformer and only one other than myself who plugs in using an EMS ... virtually everyone else simply plugs in and doesn't give it another thought. :S No wonder my own dealer does a brisk business every season selling replacement converters and microwave ovens, including myself before I figured out how damaging low voltage can be. :( Yeah, apparently "ignorance is bliss" ... until you suffer a failure and have to ante up to fix the damage. ;)

I admit it. I was in the 99.9% until we cooked the air/con unit and I started checking to see if there was a reason and found voltage as low as 98V.

One thing to note: If the voltage is good, the autoformer doesn't do anything, so you aren't changing your draw. The only time it activates is if the park supplies substandard power.

Lantley wrote:
This weekend I had my autoformer in use however no one else seemed concerned about the low voltage. Without an EMS or at least a meter I imagine they were not aware the low voltage condition existed.
As the saying goes "Ignorance is bliss"

Totally unscientific but I'd bet that describes 99.9% of RVrs. :R Of the many friends and others we know who camp I can't think of a single one who owns an autoformer and only one other than myself who plugs in using an EMS ... virtually everyone else simply plugs in and doesn't give it another thought. :S No wonder my own dealer does a brisk business every season selling replacement converters and microwave ovens, including myself before I figured out how damaging low voltage can be. :( Yeah, apparently "ignorance is bliss" ... until you suffer a failure and have to ante up to fix the damage. ;)

valhalla360 wrote:
"First question: How do you know you haven't needed one? Unless you have a voltage meter that you monitor, you may well have had 104v power and were slowly cooking the air/con compressor but it may not fail until months later at another park with good power"

This weekend I had my autoformer in use however no one else seemed concerned about the low voltage. Without an EMS or at least a meter I imagine they were not aware the low voltage condition existed.
As the saying goes "Ignorance is bliss"

"Interestingly the state chose to spend a ton of money upgrading 10 sites to 50 amp full hookup 2 years ago, instead of addressing power issues/capacity on the other 150+ electric only sites wired 40 some odd years ago. And it was never much of an issue until the trend became camping in 36' monster rigs with 2 AC's, 4 TV's,and washers and dryers."

This... Or the 45' monsters with three AC units running and no one in the coach.

jplante4 wrote:

Ralph Cramden wrote:

GordonThree wrote:


Report this park to the County building inspector, and the state building inspector. Low voltage is a safety issue.

Absolutely.....did so in 2008, and twice since as recent as last season. System has not been touched.

I dunno Ralph. If you've been there to a park with this problem a number of times in the past 10 years, I think some of that may be on you.

Maybe so, but I really like the park and started going there with my parents in the late 60's. The electric was installed sometime in the early 80's and was all 30 amp with one duplex pedestal for every two sites. No issues if not crowded or someone is on the next site that shares the same pedestal, but when crowded that's when an autoformer is a must if anything to keep the EMS from kicking out.


Interestingly the state chose to spend a ton of money upgrading 10 sites to 50 amp full hookup 2 years ago, instead of addressing power issues/capacity on the other 150+ electric only sites wired 40 some odd years ago. And it was never much of an issue until the trend became camping in 36' monster rigs with 2 AC's, 4 TV's,and washers and dryers. Most people don't understand the limitations, they buy that huge rig and use it a few weekends a year, and are clueless to what is involved or required to do so. They whip out the dogbones, plug the 50 amp rig into the 30 amp, and let er rip. Then they wonder why the microwave pukes and the AC goes poof. When that happens they expect the state DCNR to foot the bill. The state's solution to that issue is they now list them as 20 amp sites in their brochures and the reservation website despite 30 amp receptacles and 1980 30 amp wiring. It still does not stop the people with the double wide mobile homes on Memorial, Independence, and labor day weekends.

Dutch_12078 wrote:
I don't use an autoformer, nor have I run across a park to date where I needed one, but in those that prohibit them in their rules, I've found the predominate reasons are that they believe the devices somehow "steal" power, although I've never found a park manager or owner that could logically explain how that happens. The other reason has been possible liability insurance issues because the NEC prohibits the use of auto(trans)formers in RV's, which it does. I have inquired of the NFPA what the reasoning is behind the prohibition a couple of times, but I've never gotten a response.

First question: How do you know you haven't needed one? Unless you have a voltage meter that you monitor, you may well have had 104v power and were slowly cooking the air/con compressor but it may not fail until months later at another park with good power.

We didn't pick up an autoformer until we had low voltage kill and air/con unit. Then we started monitoring and found it surprisingly common to have low voltage on hot days.

Dutch_12078 wrote:
I don't use an autoformer, nor have I run across a park to date where I needed one, but in those that prohibit them in their rules, I've found the predominate reasons are that they believe the devices somehow "steal" power, although I've never found a park manager or owner that could logically explain how that happens. The other reason has been possible liability insurance issues because the NEC prohibits the use of auto(trans)formers in RV's, which it does. I have inquired of the NFPA what the reasoning is behind the prohibition a couple of times, but I've never gotten a response.

The wording of that section in the NEC is none to clear, but I think the intent of the prohibition is only to have it applied to the convert. The overall section it's in deals with the interaction of the 12V system and the 120V system (I think the term is "separately derived systems" here, but it's been a bit since I read it). If so, it makes sense that they would want full galvanic isolation between the 12V side and the 120V side, which means the transformer in the converter can't be an autotransformer but instead needs isolated input and output lines. This avoids creating a ground fault on the AC side (connecting the neutral to the chassis ground via the 12V negative lead), among other difficulties.

Assuming that's the intent, they could have worded it a bit more specifically and clearly!

GordonThree wrote:

Boosting 100 volts to 120 volts, with wattage remaining fixed (same load), means your transformer will drawing more amps over an already overloaded distribution system to make up the volts.

I can see a park with a sub-standard system being upset about blowing a main transformer or damaging lines if everyone were running their own transformer.

It will make the problem worse for others on the system that don't have their own transformer. Your transformer will only cause the voltage to drop even lower for others.

Given today's society, the me-first thinking that's popular, lowering someone else's voltage is not my problem, others can buy a transformer too of course.

Here is the statement from Hughes:

"How Does it Work?

Autoformers are used in industries to stabilize voltage and lower the operating cost of equipment. The Autoformer has 5 windings: 2 primary and 3 secondary. All models have surge and spike protection. When the unit is in Automatic and the park or input voltage is 116 volts or below, the output is 10% over the input. When the input is over 118 volts, the output is 2% over the input.

The Autoformer DOES NOT take power from the park.

It does not affect the park or input voltage, or make electricity.

What it is doing is changing the voltage – amperage relationship, lowering the amperage and raising the voltage. Since appliances run better on higher voltage, lower amperage, less overall power is used from the park, and better service is enjoyed from your RV

An Autoformer running at full output (50amps) will use 1 amp, but will cause appliances to cycle more often and run cooler. This will use less total power from the park. "

If I am reading this correctly, the Hughes works by sacrificing Amperage availability by boosting voltage based on the Wattage demand of what the RV "appliances" are demanding. Net, the ones you need running will run more efficiently, but you will not be able to run as many since the AMPS will not be available. If that is correct, a person using an Hughes Autoformer isn't stealing anything from the park or anyone else in the park.

To answer the OP's question: I have used the Hughes Autoformer with several RV's and have never been questioned by any Park I've been in. Many parks have been upgrading their electrical and I find fewer now that have low voltage issues than I used to. Although on hot days with everyone's AC going, the voltage does tend to drop a bit in mid day even in parks with good electrical. I use the Hughes to protect my AC and other "appliances" from struggling on too few volts.

I don't use an autoformer, nor have I run across a park to date where I needed one, but in those that prohibit them in their rules, I've found the predominate reasons are that they believe the devices somehow "steal" power, although I've never found a park manager or owner that could logically explain how that happens. The other reason has been possible liability insurance issues because the NEC prohibits the use of auto(trans)formers in RV's, which it does. I have inquired of the NFPA what the reasoning is behind the prohibition a couple of times, but I've never gotten a response.

Gil,
Could you give us a good estimate of power usage between an AC laboring on 100 volts, and an AC operating more efficiently on 110 volts boosted by an autoformer? Of course the one on low voltage may well burn up.