Autoformers in the News

[redbaron73]

I just read this in an email from technorv:

The National Fire Protection Agency (NFPA) has announced a change in the 2020 code that could affect how you connect your RV to power. Do you use an autotransformer/voltage regulator? These devices are designed to increase the voltage to your RV should the voltage drop on your power pedestal. These units convert amps into volts to accomplish this, and this process is now being stated to have ill-effects on surrounding power supplies. The committee for the NFPA wrote this, “The use of autotransformers places severe additional stress to surrounding electrical infrastructure not accounted for in the load calculations in this section. Park operators report that low voltage conditions typically exist when surrounding sites use these add-on devices.”
In a move to lead the way for this change in the code, Surge Guard has immediately discontinued their autotransformer models (10175 & 10176 Voltage Regulators). We have never sold these units at TechnoRV, so it will not affect anything we have sold in the past. There are other autotransformer companies on the market that will be affected by this change. I am not sure what the plan is from the other companies to conform with this new code, but I would guess that this will create change pretty quickly.

[TJ]

One needs to understand that compliance with the NFPA "Code" is voluntary rather than mandatory unless an individual entity (city, county, state, etc.) adopts it. I think TechnoRV has jumped the gun in declaring autotransformers to be on the way out.

And, the concept cited saying that autotransformers place severe stress on surrounding electrical systems is seriously flawed. This argument has been circulating for years in the RV park world without much credibility.

I would hope that information published on this forum would not cause readers to make premature decisions regarding the use and availability of autotransformers.

TJ

[Old-Biscuit]

That is contrary to what Hughes states

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.


https://hughesautoformers.com/autofo...-does-it-work/

Autoformer senses outpt voltage.....when it decreases the output voltage is increased by using a different tap (more windings) so output voltage increases W/O changing or affecting input voltage




But the use of the word 'autotransformer' is misleading
Autotransformer is an electrical transformer with only one winding. Not the same as an 'autoformer'

[Dutch Star Don]

NFPA regulations may not be used as a regulatory standard, but they are used by attorneys as the industry standard on how things should operate. Will you get sued for using an autoformer or causing issues with a campground power grid, probably not, but a smart campground will most likely use the information to prohibit them.

[spyderRV]

I built my own which merges two 1800 watt units to handle a 30 amp pedestal. It has 5 voltages levels. One straight through, two boosts and one cut. It will never pull more than 30 amps because the pedestal breaker limits me to 30 amps. I don't see how this is a problem!

[ptw]

The description of how it works on Hughes' website may be factual but it is misleading. This is a better description of how it works. This description explains how they may cause a problem for other people.

Autotransformers steal power? | Good Sam Camping Blog

Originally Posted by Old-Biscuit

That is contrary to what Hughes states

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.


https://hughesautoformers.com/autofo...-does-it-work/

Autoformer senses outpt voltage.....when it decreases the output voltage is increased by using a different tap (more windings) so output voltage increases W/O changing or affecting input voltage




But the use of the word 'autotransformer' is misleading
Autotransformer is an electrical transformer with only one winding. Not the same as an 'autoformer'

[CountryB]

People that buy the Autoformer are doing so to protect their coach because the RV park is not supplying the power they are paying for.

I think it would be a hard case to win where the Park owner sues coach owner for using an Atuoformer, or if your concerned about Park owner telling coach owner to disconnect the device, you could setup the Autoformer like the RVGeeks guys did where it is located in a storage compartment (out of sight).

[knightstorm]

“Park owners report” low voltage conditions where autoransformers are used.

I totally agree with that statement, as I only connect my autoformer if the voltage is low, so the low voltage is causing the autoformer use - not the other way around.

[CoreyinWP]

Guess I am destined to run from town to town like the fugitive!

[NealC]

I’ll be parked next to Corey in the detention lot doing leaf raking duty.

[DrPhil]

"...Park operators report that low voltage conditions typically exist when surrounding sites use these add-on devices.”

IMHO, they've got the chicken before the egg!

[Hit_the_Rhod]

Pretty typical to try to regulate/ban appliances that correct problems caused by inadequate, poorly designed, overloaded, or poorly maintained electrical infrastructure.

"Of COURSE you can add another 25 RV sites to your 120 RV site park whose electrical infrastructure was only designed to handle a maximum of 80 sites!"

[bruceisla]

Originally Posted by knightstorm

“Park owners report” low voltage conditions where autoransformers are used.

I totally agree with that statement, as I only connect my autoformer if the voltage is low, so the low voltage is causing the autoformer use - not the other way around.

Yes ... and it's quite possible that Autoformer users have consumed hamburgers during their stay ... therefore ...

[10 fan]

Originally Posted by ptw

The description of how it works on Hughes' website may be factual but it is misleading. This is a better description of how it works. This description explains how they may cause a problem for other people.

Autotransformers steal power? | Good Sam Camping Blog

There are a lot of errors and miscalculations in this article. Unless I am reading it wrong some of his examples are the opposite of OHMS law.