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04-10-2005, 08:03 AM
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#1
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Montana Master
Join Date: Dec 2003
Location: Chandler
Posts: 624
M.O.C. #740
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Hughes Autoformer Info.
Hello MOC'ers,
For anyone who has been thinking about adding an Autoformer, I found a very good Web. page with info. on the Autoformers. What they will do and won't do. Well written and thorough. http://www.phrannie.org/surge.html
For those of you that have been waiting for a sale, PPL is knocking off $100+ until the 15th. www.pplmotorhomes.com
Also there's a used 30 Amp on EBAY right now. 5 days left on the auction, 0 Bids. Might be a great deal for someone.
Happy Camping
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04-10-2005, 08:53 AM
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#2
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Montana Master
Join Date: Feb 2004
Location: Cumming
Posts: 2,820
M.O.C. #919
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Steve,
$314 is a great price on the autoformer. Also, somebody may really get a deal on the one on EBAY.
After using our coach last week, I can not say enough good about the autoformer. We have always had problems with breakers tripping because of low voltage at the Shore Power post. We did not have any breakers tripping even with the A/C and W/D going at the same time with the TV and other smaller loads going as well.
Here's another source of info at the Hughes Autoformer WEBsite if anyone is interested:
http://www.autoformers.com/learn/how.htm
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04-14-2005, 05:54 PM
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#3
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Established Member
Join Date: Jan 2005
Location:
Posts: 28
M.O.C. #3028
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Just my 2 cents here...from my I have noticed....the camp sites that have 30 amps tend to be a little low and will jump around on voltage a bit more....you crank the H20 heater and A/C and then try and run the microwave...you are bound to blow something...but more importantly the voltage drop as you run more things.......On the 50 amp sites...I tend to find that they are the newer parks or the parks that have upgraded the services...there are many new codes they have to abide by now vs 20 years ago.....I am not sure you really need one at the sites I have been to that have 50 amp service...surge protection is another matter all together though...
Good luck
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04-15-2005, 05:22 AM
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#4
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Montana Fan
Join Date: Mar 2004
Location: New Lisbon
Posts: 175
M.O.C. #1316
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I agree with Gamer1624, and so I purchased a used 30Amp Auto former, even thou my BigSky is a 50amp job. I see no reason to get the higher priced 50amp autoformer. I also purchased a 30 amp cord that I plug into my RV outlet then into the autoformer if required from the 30amp campground park. I also have a plug in guage which tells me if the park electrical service is low. Bottom line it works for me.
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04-15-2005, 06:41 AM
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#5
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Montana Master
Join Date: Dec 2003
Location: Chandler
Posts: 624
M.O.C. #740
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GAMER1624,
If I'm following the thought pattern correctly, it would seem as though it would be wise if a person with a 30 Amp Rig. not having an Autoformer,and arriving at a Park with both 50 & 30 Amp plugs on the pedestal, should use a 50/30 dog bone adapt. and use the 50 Amp plug.
It seems to make sense but, my background is Mechanical Engineering not Elect.
Is this what you are proposing?
Happy Camping
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04-15-2005, 10:51 AM
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#6
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Montana Master
Join Date: Jun 2003
Location: King George
Posts: 688
M.O.C. #345
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We also carry the Hughs 30 amp Autoformer. There are too many older campgrounds that are not wired to carry the big electrical loads that the coaches need today. It is a small price to pay for constant elcetical power and not have to worry about burning out a board or motor because of low voltage. I leave a volt meter in one of the plugs all the time so I can watch for low voltage. We too use a 50' 30 amp chord most of the time and have no problems with voltage. We watch what appliances are on if the wife is using the washer/dryer.
Ken and Velda Taylor
Dahlgren Va
2005 3475 Montana
2000 Ford F350 Diesel
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04-16-2005, 09:42 AM
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#7
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by azstar
GAMER1624,
If I'm following the thought pattern correctly, it would seem as though it would be wise if a person with a 30 Amp Rig. not having an Autoformer,and arriving at a Park with both 50 & 30 Amp plugs on the pedestal, should use a 50/30 dog bone adapt. and use the 50 Amp plug.
Happy Camping
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For what it's worth, plugging into a 50 amp receptacle with a dog bone down to a 30 amp cable still only allows you to operate on 30 amps. It has to do with the wiring. 50 amp power is 4-wire, while 30 amp power is only 3-wire.
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04-16-2005, 11:09 AM
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#8
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Montana Master
Join Date: Dec 2003
Location: Chandler
Posts: 624
M.O.C. #740
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Hello Orv,
If I'm getting Gamer1624's drift, do you think if the Pedestal with both a 50 & 30 plug might have less draw on the 50 side and have less of a chance to be drawn down, because less people might be using the 50 lines? The 50 to 30 dogbone adpts. are just deleting one of the hot leads right? If this were the case then the person with a 30 only Rig without an Autoformer would be wise to do this, right?
Does this make any sence?
Also wanted to let you know that I have followed your lead and installed the Autoformer and put the Surge Guard after it. All hard wired and out of sight. It came out great.
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04-16-2005, 02:36 PM
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#9
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Montana Master
Join Date: Nov 2002
Location: Oceanside
Posts: 20,028
M.O.C. #20
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We don't have the Hughes AutoFormer but I've yet to hear anything bad about it. Can someone give me a birds-eye view of the functions of the autoformer? We have 50amp service but seldom drag out the 50amp cord. Mostly we use an adapter and 30amp cord and plug in to 30amp service at the post.
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04-16-2005, 02:51 PM
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#10
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Montana Master
Join Date: Dec 2003
Location: Chandler
Posts: 624
M.O.C. #740
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Steve,
Here's a couple of sites with the info. http://www.phrannie.org/surge.html
http://www.autoformers.com/learn/how.htm
In a nut shell, it's a device that boosts power when the voltage comming to your coach is reduced for many different reasons. Reduced voltage can do a lot of damage to your Elect. equip. and shorten the life of things like your A/C etc.
Happy Camping
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04-16-2005, 04:34 PM
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#11
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by sreigle
We don't have the Hughes AutoFormer but I've yet to hear anything bad about it. Can someone give me a birds-eye view of the functions of the autoformer? We have 50amp service but seldom drag out the 50amp cord. Mostly we use an adapter and 30amp cord and plug in to 30amp service at the post.
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In laymen's terms, what the Hughes Autotransformer does for you is to increase the input voltage to your rig about 8 to 10%. In other words, if your pedestal voltage was 102 volts, the transformer would boost it to 110 to about 112 volts. The reason you might want the transformer is when site voltage is very low and you begin drawing on it you pull it down even more. Now consider that you might want to run your AC, refer, microwave. With the voltage low to begin with you stand a chance of burning out your AC motor. It has to do with Ohm's Law of Voltage=Current X Resistance. If the voltage goes low, resistance stays the same (AC motor resistance), thus current goes down. Therefore, if you increase voltage to begin with, then current goes up.
As I've mentioned before, I have the transformer (not Hughes, but similar), and it has saved me many times, especially in older campgrounds.
Someone previous mentioned that if a site was providing 50 amp and 30 amp service at a pedestal wouldn't it make sense to plug into the 50 amp and dog bone it down to the 30 amp cord. The answer is no. When you plug into the 50 amp and dog bone it down to the 30 amp cord, you still only have 30 amps.
Does this help?
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04-16-2005, 04:39 PM
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#12
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by azstar
Hello Orv,
If I'm getting Gamer1624's drift, do you think if the Pedestal with both a 50 & 30 plug might have less draw on the 50 side and have less of a chance to be drawn down, because less people might be using the 50 lines? The 50 to 30 dogbone adpts. are just deleting one of the hot leads right? If this were the case then the person with a 30 only Rig without an Autoformer would be wise to do this, right?
Does this make any sence?
Also wanted to let you know that I have followed your lead and installed the Autoformer and put the Surge Guard after it. All hard wired and out of sight. It came out great.
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Azstar, glad to hear everything is working great for you. As for plugging into the 50 amp and dog boning it to the 30 amp cord, you still only have 30 amps. The pedestal still only has so much amperage coming to it. If you plug directly into the 50 amp and to your coach, you will have 50 amps, but otherwise, no.
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04-16-2005, 06:06 PM
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#13
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Montana Master
Join Date: Feb 2004
Location: Cumming
Posts: 2,820
M.O.C. #919
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Azstar (Steve),
I think I am inclined to go with your idea that "dog boning" the 50 AMP to connect your 30 AMP service may indeed be better, because I think we have already established that the new 50 AMP services are generally engineered better and are probably more stable than the old 30 AMP services.
A 50 AMP Shore Power Connector can actually provide 100 AMPs of Current. There are 50 AMPs on each leg. The two legs are 180 degrees out of phase with each other so the neutral line will have no current if there are identical loads on each line (i.e. Leg A = 45 AMPs and Leg B = 45 AMPs 45 AMPs - 45 AMPs = 0 AMPs). In any case, the neutral line will never have more that 50 AMPs of current moving through it. (The amount of current on the neutral line is the difference between the current on the two legs. i.e. leg A = 40 AMPs, leg B = 20 AMPs. 40 AMPs - 20 AMPs = 20 AMPs on the neutral line.) The electrical panels in some coaches may limit the current into the coach by using a 30 AMP breaker on one leg and a 20 AMP on the other leg. You can't use more than these breakers allow. Most "newer" coaches have two 50 AMP breakers that are tied together. If one leg trips due to excess current, the other leg is turned off too. This is done for your safety so that the entire panel is unpowered if one leg trips for whatever reason.
When you use your 30 AMP "dog bone" your rig (Mountaineer with 30 AMP Panel) can only use 30 AMPs of the 50 AMPs available on that leg. Assuming that we have a good 120 Volt reading at the Shore Power post you will have plenty of power available using your "dog bone" cable. If this voltage is low, your Hughes Autoformer would also step up this voltage by changing the ratio of the windings in the transformer from 1:1 to 1:1.2 or whatever ratio is necessary to keep the voltage acceptable.
Sorry for the long explanation. My old Electronics/Electrical Engineering training kicks in ever so often.
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04-17-2005, 04:06 AM
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#14
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by fulltimedreamer
Azstar (Steve),
I think I am inclined to go with your idea that "dog boning" the 50 AMP to connect your 30 AMP service may indeed be better, because I think we have already established that the new 50 AMP services are generally engineered better and are probably more stable than the old 30 AMP services.
A 50 AMP Shore Power Connector can actually provide 100 AMPs of Current. There are 50 AMPs on each leg. The two legs are 180 degrees out of phase with each other so the neutral line will have no current if there are identical loads on each line (i.e. Leg A = 45 AMPs and Leg B = 45 AMPs 45 AMPs - 45 AMPs = 0 AMPs). In any case, the neutral line will never have more that 50 AMPs of current moving through it. (The amount of current on the neutral line is the difference between the current on the two legs. i.e. leg A = 40 AMPs, leg B = 20 AMPs. 40 AMPs - 20 AMPs = 20 AMPs on the neutral line.) The electrical panels in some coaches may limit the current into the coach by using a 30 AMP breaker on one leg and a 20 AMP on the other leg. You can't use more than these breakers allow. Most "newer" coaches have two 50 AMP breakers that are tied together. If one leg trips due to excess current, the other leg is turned off too. This is done for your safety so that the entire panel is unpowered if one leg trips for whatever reason.
When you use your 30 AMP "dog bone" your rig (Mountaineer with 30 AMP Panel) can only use 30 AMPs of the 50 AMPs available on that leg. Assuming that we have a good 120 Volt reading at the Shore Power post you will have plenty of power available using your "dog bone" cable. If this voltage is low, your Hughes Autoformer would also step up this voltage by changing the ratio of the windings in the transformer from 1:1 to 1:1.2 or whatever ratio is necessary to keep the voltage acceptable.
Sorry for the long explanation. My old Electronics/Electrical Engineering training kicks in ever so often.
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Fulltimedreamer: Your explanation is right. I'm not a EE, just a long-time electrical technician. My input to the forum results from a lot of experience with "old" campgrounds that attempt to update there power systems using existing cabling. I didn't want to mention that there were 50amps on each leg for fear of confusing people but you did an excellent job of explaining it. Even I understood. Thanks for your input.
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04-17-2005, 09:49 AM
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#15
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Montana Master
Join Date: Nov 2002
Location: Oceanside
Posts: 20,028
M.O.C. #20
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Yes, to both of you. It does help. I saved the pages from those links for further reference and read the ones from the hughes site. The other one is longer and I will read it when I get offline. Now I have to save my pennies to buy one of these things. We've been fulltiming over two years and have not yet had an appliance failure. But we have been in a few places where the electrical setup had me worried.
The Hughes site indicates we could run more appliances on 30amp. We have 50amp service but ours is effectively 30 amp. 20amps goes to the 2nd AC prep. We have the prep but not the 2nd AC. The other 30 amps goes to the rest of the coach. Our Main breaker is a double but one side is labeled 30 and the other 20. We do not have two 50's for a main like the newer rigs do. So we most often use a pigtail on the Montana to connect to our 30amp extension cord and connect to the 30amp outlet on the park's post. We can run any two of AC, dryer, microwave, electric heater on high (1500w). Turning on a third one will pop a breaker in the Montana. While running two high-draw appliances we can run 1 or more small draw items but too many will pop the breaker in the Montana. We **almost** never pop the park's 30amp breaker. So, if the autoformer would allow us to run 3 high draw items simultaneously, that would be a major benefit for us. Not to mention the other benefits.
Thanks again.
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04-17-2005, 03:12 PM
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#16
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by sreigle
The Hughes site indicates we could run more appliances on 30amp. We have 50amp service but ours is effectively 30 amp. 20amps goes to the 2nd AC prep.
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Our 2000 Montana is also a "50 amp" coach. 30 amps for the coach and 20 amps for the washer/dryer which we never purchased. I don't know if there is a true 50 amp coach unless it's like yours--2 ACs. When we are in parks where 50 amps is available, we always plug into the 50 amps. This way I have 30 amps for the coach and I installed another 20 amp receptacle off a spare breaker where the other leg is tied (same leg as where the washer/dryer hookup is). Then when it is cold out I can use my little "cube" heater without affecting the other 30 amp leg.
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04-17-2005, 05:35 PM
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#17
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Montana Master
Join Date: Nov 2003
Location: Glendale
Posts: 1,219
M.O.C. #635
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For what it is worth, an autotransformer works by changing the "power factor" in the electrical system. If you look at a voltage or current wave form in a normal ac electrical system , you will see a very nice sinisoidal wave form. in a perfect system, these waves will be in synch. Devices like electric burners on your stove are almost perfectly resistive. Current and voltage waves from such devices are usually perfectly in synch. If you add more reactive resitance (usually from motors and other wire wound devices), the current wave form will begin to shift. Even if the load is less than the specified current load for a perfect device, the electrical system will begin to fail. One solution is to add capacitor type loads into the system to bring the power factor back in line. This is the ideal, however, there are not a lot of such loads available to the average consumer
Another solution is the autotransformer which has a set of windings that tend to pull the current wave form back into line with the voltage wave form. Unfortunately, this approach creates extremely distorted "sine" waves. Not all equipment respond favorably to such distortions
Heavily loaded lines can be brought back up to proper "voltage" by these devices but, the improper power factor and distortated wave form have the potential to damage equipment. My point -- TISNSTOFAL--an old dutch expression (there is no such thing as a free lunch), It is far better to find the problem, plug into a proper electric circuit. INMHO an auto transformer is a bandaid that may lead to larger problems
Dave
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04-18-2005, 01:20 PM
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#18
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Montana Master
Join Date: Aug 2004
Location: Cedar Rapids
Posts: 4,876
M.O.C. #1944
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Quote:
quote:Originally posted by Dave e Victoria
My point -- TISNSTOFAL--an old dutch expression (there is no such thing as a free lunch), It is far better to find the problem, plug into a proper electric circuit. INMHO an auto transformer is a bandaid that may lead to larger problems
Dave
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You're absolutely right. TISNSFOFAL. However, I'd rather be safe in an old campground with questionable wiring by using my autotransformer. With a surgeguard between it and my coach I don't have the worry of being connected to bad power.
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