electrical autoformer

Dwight · 10-13-2003, 07:50 AM

Does anyone have any experience with either the Hughes or Frank's Autoformer (voltage booster)?

RoadKingMoe · 10-13-2003, 09:42 AM

No experience, but all the Hughes consists of is a buck-boost transformer wired up to increase input voltage, whether it be high or low, by about 10%, in addition to the low/high voltage and surge suppression circuits of other power protection devices. The cost of this is a 10% increase in input current.

The 50A model is just two 30A models, one for each leg of power, and each with a higher rating (6000W vs 3600W), in one box. The "joules" protection rating per leg is the same as the 30A model.

Read more about these transformers here.

[on edit] Let me add this. Many folks think that the "auto" means some kind of automatic regulation of voltage that increases the boost to maintain 120VAC as the input voltage drops. This isn't the case. With the taps wired for 10% boost, if the input voltage is 120VAC, the output voltage is about 132VAC. If input is 100VAC, output is 110VAC, and so on.

Dwight · 10-13-2003, 10:37 AM

RoaadKingMoe,

Do you use any surge protection for your rig?

RoadKingMoe · 10-13-2003, 11:06 AM

Maybe I should, but I don't except for the surge suppressors for the computer and TV equipment. Don't have one on my house.

**john hd** · 10-13-2003, 11:53 AM

dwight,

one member here had a auto transformer on his rig because of low voltage. it did not last long.

i have always maintained that if you have crappy voltage at a campground you are paying good money for vote with your feet. find a better park to stay at. and tell the owners why you are leaving.

that works fine for recreational campers, fulltimers may not have that option.

auto transformers only raise the voltage for you leaving everyone else less available current to use. thats great until everyone gets one.

if you are at a park that is individually metered, complain to your power company. they have voltage standards they must adhere to.

as for surge protection, everyone connected to a power company transformer has it. on the primary side, ranging from 2400volts to 14,400 volts. i added a pic below.

the only ways one can get a "surge" is from lightning, losing a common neutral on your entrance, transformer malfunction(rare), or a higher voltage conductor touching your line (even rarer).

i don't have surge protection either, except for the one on the pole in front of my house!

those little strips don't stop a good shot of lightning anyway, that's what this is for. the .22 shell ejects the ground conductor after the unit operates. clearing the line to be reenergized by a circuit breaker or a lineman.

john

classic67 · 08-06-2006, 07:16 AM

Good thread. So in other words, I take it from the opinions in the thread that I should not waste the $116.00 that the camper supply store wants for the 30A surge protector? I was already to buy it because it seemed like cheap insurance as opposed to having replace damage componets in the trailer. But if it really is unnecessary, then it makes no sense to purchase for just a feeling of being protected. Does everyone agree, or is this still up for debate?

davidz71 · 08-06-2006, 08:14 AM

I bought the Hughes Autoformer because I noticed that the voltage at one campground was right at the edge of the 113 v. mark on my meter. I also spotted this several times during the evening hours at the house when the trailer is plugged into a 15 amp circuit to power the Intellipower for fans/battery charging. I've had the Autoformer for almost a year and it keeps the v. meter well into the green area, usually 123 volts.

I live in an area on a plateau rich in iron ore. It is not unusual to have lightning strikes hitting trees. Matter of fact, a couple were having a picnic when the sky turned black and they observed a sheet of rain heading their way. They grabbed the picnic basket/blanket and ran for the truck. He got there before she did to unlock the truck. He got in and saw her running in front of the truck. A lightning bolt hit the ground nearby and it literally blew the clothes off her body. She survived but the clothes didn't. We also lost 2 VCR's and 3 TV's due to lightning strikes. The last VCR and the last TV's went right through the surge protector we bought after losing the first equipment. One strike took out 12 TV's on our street alone. A number of us on the block complained to the electric company and they came out to look at the transformers on the pole. Funny thing, the transformer on the pole next to our driveway and feeding our house was replaced. The linesman also looked at our distribution box (fuse box) and found the main wires loose. He said that it could have been from repeated strikes. We've had strikes since then but no equipment has been damaged. We've been in the room and heard the surge protector pop after a lightning strike.

Is it worth having a surge protector? Only you can answer that. I've heard people recommend that if you have the Hughes, you should have an additional surge protector in front of it because even Hughes says that a lightning strike may damage the unit inside and it is not cheap to fix. I have been thinking about it but haven't made up my mind yet.

FrenchBern · 08-06-2006, 10:02 AM

And I always thought and used an autotransformer to keep the voltage fairly constant at work. The term auto means it adjust itselt to a fairly constant output voltage if within a specified load. If the unit you mentioned is nothing but a transformer with a different turn ratio winding, then I would recommend using a variac which is manually adjusted to the voltage you desire.
A lightning arrestor limits the voltage spikes across the line to a lower voltage which otherwise would damage electronic equipment. I have lost a lot of equipment while living in the country at the end of a long power line transmission. After installing an electronic arrestor across the input line coming into the house I have not lost anything else.

classic67 · 08-06-2006, 10:31 AM

Quote:

Originally Posted by FrenchBern

A lightning arrestor limits the voltage spikes across the line to a lower voltage which otherwise would damage electronic equipment. I have lost a lot of equipment while living in the country at the end of a long power line transmission. After installing an electronic arrestor across the input line coming into the house I have not lost anything else.

So French, you think it is a good idea to invest the $116 into the 30a surge protector? I'm thinking now, it can hurt but only help, right?

Does anyone know if the newer airstreams have this 'Auto-transformer' as part of the built-in electrical? Specifically, is this buil into the power box located under my front sofa? Or is the only electrical protection from A/S the circuit breakers in the back bedroom for too much draw? Thanks for helping this rookie (me)!

Gunnyusmc · 08-06-2006, 10:36 AM

I have a surge protector and auto former wired into my 2006 Safari FB. Mine are under the bed, which is were your cough is.
Location will depend on were you 110 power supply comes in.

Don

SafeHarbor · 08-06-2006, 11:44 AM

John HD brings up an interesting point (to me, anyway). Right now I'm in a very old campground that was built in the 50s. The entire in ground wiring system was last replaced in the 80s.

When the occupancy is low, there's plenty of juice for everybody. Let the park get half-full or more, however, and the voltage drops. This is particularly true in the evening just as the working folks are getting home and cranking up their ACs.

I can tell when the autoformer is boosting because I hear the fan in the air conditioner speed up. I also have a backup power supply for my PC. Typically, I'll hear it come on, then the AC fan slows, and the boost comes on a few seconds later, the backup power supply cycles back to shore power, and I'm a happy camper.

So, oh goody, I have nice juice to run my old air conditioner.

When my autoformer is engaged, am I getting more power at the expense of my neighbors?

I guess so, but it's preserving my air conditioner.

And they could buy one, too, if they want one. I'm not sure what the net effect of THAT would be. In fact, what would be the net effect if everybody in the park had an autoformer? My guess is that it would cost the RV park a lot of watts to run all the transformers, but everybody would get the benefit of more voltage. (I may be all wrong in this, too.)

Do I think this is unethical? Not really. Right now my nearest neightbors on this leg of the circuit are two motorhomes with dual ACs. One is new, so I don't know what electronics control the power in it or what capabilities it has. I know when he turns on both ACs - because my voltage sags and my autoformer has to pick it up.

Dwight, I've had the Hughes 30-amp autoformer for about two years now. I've unplugged it sometimes in thunderstorms (we have some terrific ones here), but I've never had a minute's trouble with it.

I'll be packing it away soon. I'm moving, and the Airstream will have it's own pole and meter where I'm going. I'm ready to go - waiting for EMC to come hook up the juice this week.

Lamar

davidz71 · 08-06-2006, 01:46 PM

Quote:

Originally Posted by classic67

So French, you think it is a good idea to invest the $116 into the 30a surge protector? I'm thinking now, it can hurt but only help, right?

Does anyone know if the newer airstreams have this 'Auto-transformer' as part of the built-in electrical? Specifically, is this buil into the power box located under my front sofa? Or is the only electrical protection from A/S the circuit breakers in the back bedroom for too much draw? Thanks for helping this rookie (me)!

Check www.rvwholesalers.com for good prices on 30 amp surge protectors. Autoformers are purchased aftermarket and can be either plugged into the campground power pole (they are out in the weather and must also be chained to the post or they may be stolen) or an installation kit can be purchased which allows you to mount them in a compartment where your 30 amp power cord comes into the inside of the trailer. Mine is under my double bed at the rear of the trailer. I opened the galvanized junction box, disconnected the 30 amp connections and pulled about a foot into the trailer. I mounted a female receptacle to it that came with the kit. The Autoformer male plug fits into it. The 4-5 ft. cord with male plug fits into the female receptacle on the autoformer and is then wired into the galvanized junction box just like the 30 amp power cord use to be. Power then goes up to the fuse box and into the trailer. The equipment is out of the weather and will not be stolen if the compartment is locked. Go to the Hughes sight and look at the installation kit. It is simple to install.

**john hd** · 08-06-2006, 02:50 PM

craig

good idea and i think auto transformers have their place if moving is not an option.

however, i would be leery of having any lightning arrestor inside the trailer. the reason being the metal oxide varistors that do the actual surge protection basicly explode when they operate. it is the nature of the beast.

keep them outside and locked up somehow if need be.

john

davidz71 · 08-06-2006, 05:44 PM

Quote:

Originally Posted by john hd

craig

good idea and i think auto transformers have their place if moving is not an option.

however, i would be leery of having any lightning arrestor inside the trailer. the reason being the metal oxide varistors that do the actual surge protection basicly explode when they operate. it is the nature of the beast.

keep them outside and locked up somehow if need be.

john

Thanks John, I haven't thought about that.