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TheGreatleys · 08-16-2017, 06:49 AM

Quote:

Originally Posted by bertheep

Ok...I am making progress thanks to all of the advice. "Baby Steps"

I plugged the surge protector into the outlet directly and all lights are green, no
reverse polarity. So the source is ok. I checked my extension cord and it is ok as well. When I plug the AS in the red light indicates reverse polarity. I checked my EMS and have an error code E1 which indicates reverse polarity. When I turn my EMS off I still have power to the AS and the surge protector still indicates reverse polarity. Is my EMS unit faulty?

That means your problem is inside the Airstream at or before the EMS. Check all the wiring from the point of entry to your EMS to find where the wires are backward. The issue is far more likely to be a wiring error than a faulty EMS. I would check your wiring inside the EMS first.

rvb · 08-16-2017, 09:27 AM

Lots of good advise in these responses.

I have a Progressive Dynamics inboard surge protector with the digital readout. It has paid for itself in the 2 years since I installed it. I have had 2 - faulty ground, 1-reverse polarity and at least 6-low voltage shut downs. A friend had a surge protector that only protected for high voltage and left both A/C 's on and went to town. When she got back the voltage was below 90v and both A/C compressors were toast.

Right after I bought ours, we stayed at a well known RV park West of Sante Fe. I had a ground fault reading on the 30A and told the manager. He came out, looked at my trailer and said you don't even have a surge protector at which point I showed him it was inboard. He said he would have to shut the entire row down to fix it and wasn't going to do it until the row was empty. I connected to the 50A with an adapter and it was fine. I was not impressed. At Cohokia RV Parque in E. St. Louis I had a ground fault reading. They moved me to the next space and replaced the entire pedestal within 30 minutes!

In addition to the inboard protector, I carry a $5 polarity tester, 120 to 30A adapter, 30A to 50A adapter and a multi-meter and check everything each time I hook up.

Mollysdad · 08-16-2017, 11:53 AM

Found one of these at an RV show. It has a 50 amp connector, and it "talks" to you to explain the situation. It's good for checking the pedestal before plugging in.

OTRA15 · 08-16-2017, 12:44 PM

FYI and FWIW, here are the search results for "EMS reverse polarity:"

https://www.google.com/search?q=ems+....0.VQ1K-nqkif0

. . . using the blue- bordered search box above, in case there are some odd-ball explanations scattered throughout airforums.com over recent years.

It will be good to learn something about the cause.

Peter

FYI and FWIW

bertheep · 08-16-2017, 08:07 PM

Quote:

Originally Posted by lsbrodsky

You have me totally confused now. You have an EMS and you bought an additional surge protector? The EMS includes surge protection. Your EMS can be turned off? I am familiar with a bypass capability for an EMS, but not turning it off. What model EMS do you have? Are both the EMS and new surge protector indicating reverse polarity?

Larry

Hi Larry...
Sorry for the confusion. I am not familiar with all of these things and I obviously misspoke. I turned the bypass to the off position. I don't know where my EMS is even located. This is all new to me. I did not know that the EMS included surge protection. This is my model number...EMS-HW30C rated at 120V/30A. Yes, both the EMS and the plug in protector indicate reverse polarity. I have a E1 error code when I turn the EMS on.

lsbrodsky · 08-17-2017, 02:19 AM

OK, that is a good EMS. Go back to the post above. You have a problem in your trailer. The reason you have power when you flip the EMS switch is that is just bypassing the EMS. Since you are not familiar with this stuff, you will need a qualified electrician, one familiar with RV's preferred, to check out your wiring. It may be as simple as your EMS was installed incorrectly. Since both devices are telling you reverse polarity and the source is OK, it is not a faulty indication. Oh, and your EMS does include surge protection. Look up the specs on the internet.

Larry

OTRA15 · 08-17-2017, 03:43 AM

Quote:

Originally Posted by lsbrodsky

. . .
Look up the specs on the internet.
. . .

Or in the owner's manual which came with your EMS, bertheep. It would be good to read the entire manual, as it may have some trouble-shooting advice for each of the fault sensors, including the reverse polarity issue under discussion.

Good luck!

Peter

bertheep · 08-17-2017, 05:13 AM

Quote:

Originally Posted by lsbrodsky

OK, that is a good EMS. Go back to the post above. You have a problem in your trailer. The reason you have power when you flip the EMS switch is that is just bypassing the EMS. Since you are not familiar with this stuff, you will need a qualified electrician, one familiar with RV's preferred, to check out your wiring. It may be as simple as your EMS was installed incorrectly. Since both devices are telling you reverse polarity and the source is OK, it is not a faulty indication. Oh, and your EMS does include surge protection. Look up the specs on the internet.

Larry

Thanks for your help Larry. One more question. Everyone has been saying do not plug my AS in. I have had my unit (2005 Safari) for several years now. We have obviously had this problem all along and I have never known it, and we have been using it with the EMS bypassed. Therefore I have not had surge protection all this time. Also, everyone talks about shock potential.
Since I have been using it for years and never noticed any problems have I just been lucky (and dumb)? We are planning a trip to Jackson Center in October to deal with a few other issues. Do you see any problem with waiting until then to deal with this problem? What would cause anyone in my traer to get a shock? Thanks in advance for all you help.

OTRA15 · 08-17-2017, 05:18 AM

Please check the EMS user manual. In my lay opinion, a reverse polarity problem could be deadly.

With the risk of electrical shock, "guilty until proven innocent!"

Good luck.

Peter

lsbrodsky · 08-17-2017, 05:50 AM

Bertheep,

Reverse polarity is not an equipment issue. None of your AC loads care whether the polarity is reversed. It is however a potential safety issue in that the hot wire is now connected to the outlet spade that should be the neutral wire. I have really never thought through this for the AS. Most loads like the TV's, the water heater, or the battery converter/charger are not going to present a hazard to people with reverse polarity. However, you could plug something in to an outlet that could be dangerous, a toaster might be an example. Some appliances are built expecting the case to be at ground potential. On our trailer, the ground and neutral are not connected together, but they are at the electrical source.
I would never advise you to wait to correct a clear electrical safety problem; there is no telling what action might result in a deadly shock. I'd get it fixed immediately.
Larry

uncle_bob · 08-17-2017, 09:13 AM

Hi

Ok here's how reverse polarity can kill you:

In a proper wiring setup, the switches and breakers go in the "hot" lead. Nothing goes in the "neutral" leg ever. The idea is that the neutral will always be there as a solid connection at near ground potential (it's bonded to ground for this reason).

If you reverse things, the "hot" now is on the un-switched / no breakers or fuses lead. The neutral is being switched. Drop a brick on a power cord and crush it. The lead that is actually hot in this case has no breaker in it. If it shorts to ground, nothing stops the current. There is no breaker, it's off in the neutral lead that has no current. Next step is a fire in the trailer.

So, yes, it's worked so far. You haven't had an accident so far. Safety devices are there to protect you if you do have an accident.

Have somebody good look at this. What you are seeing does not make sense. There is something weird going on. We are guessing at what the issue is. It could be something much more serious.

Bob

Gleverett · 08-18-2017, 05:46 AM

Someone stated your loads don't care if its reverse polarity. My propane furnace literature states do not use if the polarity is reversed.

lsbrodsky · 08-18-2017, 06:30 AM

Your propane furnace has a DC motor and polarity does matter. AC motors have no polarity, which is the Heat Pump/Air Conditioner, maybe the turntable in the microwave. The other AC loads are not even motors.

Larry

uncle_bob · 08-18-2017, 07:19 AM

Hi

Your AC loads will run fine with all sorts of wiring errors. That's what makes some of this so dangerous. You have no real indication that you have an issue. Along comes a fault and the protection you were counting on isn't there ....

Bob

OTRA15 · 08-18-2017, 08:58 AM

Quote:

Originally Posted by bertheep

. . .
. . . Do you see any problem with waiting until then to deal with this problem?
. . .

Hope you have been monitoring all the good advice, and are still alive and well . . .

SilverHouseDreams · 09-08-2017, 05:40 PM

I have a story on this subject to share.

We picked up a 2011 Sport 22FB a few weeks ago, an EMS was initially on my "must add list" but after seeing the $$ stack on on the credit card for all of the accessories I was buying for a "ready to go" trailer I had second thoughts. I deleted the EMS out of my Amazon shopping cart and figured I'd buy it for next season.

One night I actually had a weird dream, I suppose if I was religious I'd call it a revelation. Essentially my mind had conjured a scenario where the EMS would have saved my 2.5 year old daughter from something horrible. Not one to argue with what my mind comes up when I am sleeping I ordered the EMS (Progressive Industries HW30C) the next morning. I installed it before our maiden voyage.

We arrive at the camp ground, I plug into the 30A shore power...and go back in side to switch the fridge from propane to A/C and get a fault. I actually went back to double check the breaker on the pedestal before thinking to look at my EMS, the EMS was flashing an error for reverse polarity. Funny that, the first time I visit a CG and the pedestal is wired wrong.

I laugh about it, and then grab my multimeter and go to the pole and correct the problem. Just as I had expected the black wire coming out of the breaker was installed into the connector clearly labeled "white" on the back of the shiny new receptacle. No doubt some well intentioned CG employee decided to replace that receptacle in the past few weeks, and perhaps they were accustomed to seeing "hot" and not "white" on the receptacle.

So I left the pedestal better than I found it, legal and safe. Personally I have a lot of experience with single phase power so I was too put off by this, but I now am thinking about a way to make my own interposer box for correcting this in-line rather than within the pedestal. I'm not always going to be patient enough or trusting enough, to wait for the CG personnel to fix the problem. I see the issue with an in-line box for correcting this is making sure that the box itself has a circuit breaker in the event the pedestal has its breaker on the wrong wire as well. Should I use a GFCI circuit breaker or a regular, off to self debate or wait for a nighttime revelation.

uncle_bob · 09-09-2017, 08:27 AM

Quote:

Originally Posted by Xipper

...... I see the issue with an in-line box for correcting this is making sure that the box itself has a circuit breaker in the event the pedestal has its breaker on the wrong wire as well. Should I use a GFCI circuit breaker or a regular, off to self debate or wait for a nighttime revelation.

Hi

Just use a regular breaker.

Given the multiple mistakes Buba may have made, the magic box could get a bit complicated. There's also the "fun" of trying to work this or that out in the rain / dark / wind as you hook up. Some sort of indicators on the box are probably called for. Next up is weatherproofing it to some degree.

Yes, I just turned a dead simple adapter plug into a nightmare .... sorry about that.

There's also a bit of a "what about the next guy" in this as well. Reporting it and getting it fixed protects that next camper on the site. Fiddling your side and moving on ... not quite the same thing ...

Poking around inside a "public" box without the right license for that locality may or many not be kosher. There are lots layers to the regs on that stuff. Not clear that Buba from the office has any sort of license either ....

Lots of twists and turns.

Bob