Surge protector science

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MtnGoat

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I've been watching a bunch of RV videos on YouTube. Some of these discuss the needs for an electrical inline surge suppressor. Citing bad wiring and unstable power that can cause havoc in our trailers. There's a plethora of models and features that discover power/wiring faults.

My question is there any suppressor (or other device) that "auto corrects" the wiring faults?
 

Back2PA

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Arch Hoagland said:
In a word....No

As Arch succinctly stated, no, nothing can correct faults. The closest is an autoformer which can correct (by about 10%) low voltage, and which does have some surge suppression built in.
 

MtnGoat

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I figured with all the gizmos there'd be one out there.  Guess I need to invent one then... ;)

 

TheBar

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The best I've found cuts off the current for a few minutes when the voltage gets too high or too low. Both can cause damage and low voltage is more common than most people realize.
 

John From Detroit

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There are several faults  The most common is UNDER (or over) voltage. A hughes Autoformer (And selected Competors) can do SOME correction. one model also handles over (But only one That I know of and I forget the make)

Also you have Reverse Polarity... (Black and white wires crossed) 
Open Leg ground or neutral

The only waw to fix those is with a Screwdriver.
 

Gary RV_Wizard

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An automatic wiring fault corrector is feasible from an engineering viewpoint  but not simply too expensive for RVing use. Auto fault detectors are expensive enough ($300+ for the 50A version) without adding an array of high-amp switches to do the auto-correction
 

Rob&Deryl

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Some of the bad wiring at some campgrounds can kill you. You really want a device that detects a dangerous (or possibly expensive - think all electronics fried) connection and prevents the trailer from powering on.

Suppressing surges, not a big deal. Detecting a badly wired pedestal, priceless.

When I get my trailer, I plan to wire one in rather than the plug on versions, not that plug on is bad. I want it to be mandatory for me.
 

Gary RV_Wizard

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I don't want to belittle the value of a powerline monitor (EMS), but a little perspective doesn't hurt either. We've RVed for 20 years, anywhere from 2-6 months per year and all over the USA and parts of Canada.  The last 10 years of that with a hardwired system so every campsite was rigorously tested and monitored.  Have encountered maybe a half dozen wiring faults in all that time, mostly reversed neutral & ground or open ground.  Had an additional 8-10 voltage faults, mostly high in more recent years. Low voltage was more frequent back in the late 90's, though.

People ask if these devices are totally necessary. To me, the answer is clearly No. Chances are you can get through your RVing life without ever encountering a damaging fault, at least not a serious one.  But when & if the day comes, you will be really thankful for the extra insurance of a power monitor EMS. 
 

docj

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Gary RV_Wizard said:
People ask if these devices are totally necessary. To me, the answer is clearly No. Chances are you can get through your RVing life without ever encountering a damaging fault, at least not a serious one.  But when & if the day comes, you will be really thankful for the extra insurance of a power monitor EMS.

Like  most "insurance premiums" the chances are pretty high that you'll never need the coverage, but you can't judge beforehand which park pedestal you're going to use will have a problem. 

One might think that the problem is more common at old, dilapidated CG's, but that's not always the case.  A couple of years ago we had an intermittent high voltage issue at our virtually brand new pedestal on our own property in TX.  We knew the problem existed because our Progressive EMS repeatedly would cut out and then reconnect.  A power company technician tightened every connection from the distribution transformer to the pedestal and, sure enough, the problem went away. (If you weren't aware,a bad connection can lead to resistance and low voltage on one leg of a center-tapped circuit while creating high voltage on the other leg.)

Would that issue have caused us problems if left uncorrected?  I can't prove it would have, but IMO it's nice to know that things like that will be discovered before they create serious problems.
 

Back2PA

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docj said:
One might think that the problem is more common at old, dilapidated CG's, but that's not always the case. 

docj raises a very good point. A couple of years ago I found myself at a very expensive "resort" style RV park in Arizona. At the time I had my 2005 Dutch Star, and I had the oldest rig in there - I was surrounded by half million to million dollar rigs. The only reason I was in this park was I was preparing for a move cross country and I needed to be in that location for a few days. It was the middle of summer and both ACs were running hard all day. I returned to the rig after being out, and the ACs sounded funny. Glanced at the volt meter and it read 230V! Ran to the bedroom to look at the analog meter and it was pegged high. Ran outside and tripped the breakers at the pedestal.

Burned up my convection microwave and battery charger which, being part of the converter/inverter meant the whole thing had to be rebuilt. Amazingly neither AC was damaged. I tested voltage at the pedestal (now with no load) and everything was fine. I complained to the front desk that I thought the neutral was intermittent. The park electrician came out and did the same simple voltage test, declared the pedestal to be fine and the park refused to take responsibility.

I had a plug in surge protector (which was also destroyed but did not protect the rig) but did not have an EMS.
 

MtnGoat

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Picked up a EMS-HW30C with the monitor panel. I figure having it hard mounted will avoid the concerns for theft. Should at least warn me if a problem is at hand.
 

SargeW

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My experiences with voltage dropouts have been much more common than they used to be. Often it has been in parks that are not that old, but have many 30 amp only sites. Since a good portion of the mid size and smaller RV's are 30 amp, if the campground has used Line 1 feed in all of their 30 amp pedestals and also continued the same line into the 50 amp sites, on a hot day Line 1 gets hit pretty hard. 

If I am at the end of the line so to speak with many other RV's running their AC's, I will see regular drop out of the Line 1 voltage below the 109 volt threshold of my  Surge Guard.

It is a symptom of the rapid escalation of RV sales in the last few years. More families out RVing, more baby boomers jumping into the lifestyle.  Many campgrounds can't keep up with the demand. RV sales have flattened  as of late though.  I think your purchase of the surge protector was a great idea.
 

MtnGoat

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Thanks all for your input and opinions.
Hearing these stories helps me realize the need for some protection.
But not to be surprised if it doesn't help.

Cheers!
 

knucklebucket

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while there are some valid points. you do have the option to install a power conditioner.  a power conditioner acts in sorts like a voltage regulator( basically it attempts to correct power factor). it helps smooth out the wave form of electricity to give you a cleaner consistent supply. but if you plan on conditioning power throughout entire coach it could become expensive.
 

MtnGoat

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Installed the EMS and a connection check. It does generate some heat that I'll keep a watch on for now.

The display reads out line voltage, cycles, amperage & error codes. Although the display is red, the continuous flashing of data is too bright for this kid at night. I'll just cover it with a book.

It even displays  error  code  E-10.  This is indication that it needs to be replaced.

:)
 
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