Community Forums

DMD · 06-22-2016, 11:12 AM

I have reversed AC polarity when plugged into 120vac. 2004 Trail Lite Workhorse 8.1L. While plugged in at the Drag Strip, my 30amp plug & adapter melted down. After installing a new 30amp plug I tested my Motor Home receptacles; they have reversed polarity. I think they tested OK last year, but I didn’t test them this year. I rechecked to make sure I wired the plug correct. Then I looked at the wiring in the power panel – all the blacks are on the breakers, all the whites are on the same terminal block & all the grounds on another block. My power center is labeled as a 55 amp Converter Charger Model 7355, but I don’t see a brand name. If I unplug from the AC & just use the generator, the polarity tests fine in the same receptacles. Anything I plug into the receptacles works fine even though the polarity is reversed when I’m plugged into AC. What does it hurt to have the polarity reversed? Could the converter charger be bad or if it were, would the polarity still be reversed when I use the generator? Thanks much for your consideration.

nothermark · 06-22-2016, 11:28 AM

How did you test the "polarity"?

If it tests OK on the generator then I strongly suspect the unit is wired correctly and the problem is your adapter or the source.

Skip426 · 06-22-2016, 11:40 AM

Welcome to iRV2.

AC power , reversed polarity ( hot neutral to some ) can be dangerous because some appliances won't tolerate it and touching the metal housing on certain AC powered items while grounded can give you shocks.

If you're sure the house or park plug that your , getting the power from is correct , and that the new pugs wires are in the right place, then checking for burnt wiring inside the auto transfer switch would be the next place to look.

Your converter/charger should not be the issue. But to test you could disconnect it or shut off the circuit breaker that feeds it power.
The black wire in your power cord and the new plug , should be on the pin that goes to terminal H in the diagram and the white wire in the cord to terminal N.

Old-Biscuit · 06-22-2016, 11:42 AM

Your rig is wired correctly......Black on breakers etc
As evidenced by it being correct when AC is supplied by YOUR generator

The AC Power Source at the Drag Strip is wired 'reversed'.........their 'Neutral' wire is connected to hot lug and the 'Hot' is wired to the neutral lug on the receptacle.

As far as AC 'electric' this is not an issue.........but it is a potential shock hazard.
Neutral wire remains HOT when Circuit Breaker is open

Gary RVRoamer · 06-22-2016, 06:42 PM

Quote:

What does it hurt to have the polarity reversed?

There is a definite danger of shock or electrocution. Not for most things, and not when everything is working tight, but if anything ever goes wrong in the RV wiring or an appliance, you could get hurt. There is a good reason things are wired as they are, hot, neutral, and ground. Plus, some digital electronic devices will NOT work with neutral and hot reversed.

You connected the black and white wires of your shore cord to the wrong pins on the 30A plug. Won't take much effort to remove the plug and reverse those two wires and then you will be safe again.

FreedomDream · 06-23-2016, 06:32 AM

Your shore power (or, if you are using one, your dog bone 30 amp to 50 amp adapter) is wired incorrectly. You know this because your generator is producing the correct polarity AND the reverse polarity only occurs when you are plugged into shore power. Fix your shore power.

DMD · 06-23-2016, 08:47 PM

Thanks! to every one of you for your responses. Also, thanks for the Welcome & diagram. It turned out to be the adapter. Since my orig adapter melted down I bought a new one of the short (about 1" long of rubber) ones that has the 30A female on one side & the 15A male on the other. When my son in law heard about my delema he said he had a similar situation then an RV dealer in our area told him he would be better off to have the other style adapter that has cable between the male & female. You guys can tell me if there is a reason why the long style would be any better? Anyway he bought the long one, went to a rodeo event - other people's adapters were melting, but his didn't. Based on his testimony, I bought one from Menards for about $9 that has 6" of cable between the 15A male & the 30A female. It also has an LED that lights when I plug in the 15A letting me know there is power there. The problem is, they didn't wire it correctly internally. The White of one end is connected to where the Black should be on the other end. I just trusted it because it was new, so thanks again for the suggestion that it would be bad. I used my short adapter and the receptacles tested good! I'm glad I found this site.

Skip426 · 06-23-2016, 09:04 PM

We're glad you're here and that your fixed up , and that you've taken the time to wrap up you post .

Safe Travels.

Ray,IN · 06-23-2016, 09:48 PM

Quote:

Originally Posted by DMD

I have reversed AC polarity when plugged into 120vac. 2004 Trail Lite Workhorse 8.1L. While plugged in at the Drag Strip, my 30amp plug & adapter melted down. After installing a new 30amp plug I tested my Motor Home receptacles; they have reversed polarity. I think they tested OK last year, but I didn’t test them this year. I rechecked to make sure I wired the plug correct. Then I looked at the wiring in the power panel – all the blacks are on the breakers, all the whites are on the same terminal block & all the grounds on another block. My power center is labeled as a 55 amp Converter Charger Model 7355, but I don’t see a brand name. If I unplug from the AC & just use the generator, the polarity tests fine in the same receptacles. Anything I plug into the receptacles works fine even though the polarity is reversed when I’m plugged into AC. What does it hurt to have the polarity reversed? Could the converter charger be bad or if it were, would the polarity still be reversed when I use the generator? Thanks much for your consideration.

Oddly enough, two years ago I bought a male and female replacement plug ends from Camping World to replace the worn, burned ends on my 30A extension cord. I wired both ends per color coded wires. Nothing worked right, so I disassembled both end plugs and double-checked my wiring, which was correct per color coded wires.
Plugged the cord in, same reversed polarity condition. This time I got my VOM meter and checked each of the 3 prongs while plugged into 120VAC. The male plug was reversed polarity, so I disassembled my splice and checked each wire to prong for continuity. When the replacement plug was made someone had switched the red and black wires in the molded male plug.

I switched the wires and now it has red to black, and black to red in my splices; BUT now polarity is correct.

DMD · 06-24-2016, 10:29 AM

Thanks for your replies. I have a call in to "Smart Electrician" customer service to tell them the problem so that someone else won't have reversed polarity.

mervcoulter · 06-24-2016, 10:46 AM

I have. A 2007 fleetwood revolution that. The front door latch won't open from the outside. I took the lock apart and it seems like a very simply operation but I can't find any reason for it not to work. The lock has been replaced by a much more complicated part and costs $200. Any suggestions for a cheaper fix?

Gary RVRoamer · 06-24-2016, 03:50 PM

The "long" adapter isolates the heat generated at the shore cord plug from the heat generated at power pedestal outlet and gives more space for each to cool. This can become important if running near max amps for hours at a time. Be aware that the rating of an outlet is max or peak load, and it is expected to run at only 80% of that on average. Thus a 30A outlet is designed for a sustained 24 amps and will often overheat if run at 25-29 amps for hours.

It is also handy for boxes or outlets that may be small or awkwardly placed. The male plug end is smaller and the cord gives some flexibility in placement.

Skip426 · 06-26-2016, 10:05 AM

Quote:

Originally Posted by mervcoulter

I have. A 2007 fleetwood revolution that. The front door latch won't open from the outside. I took the lock apart and it seems like a very simply operation but I can't find any reason for it not to work. The lock has been replaced by a much more complicated part and costs $200. Any suggestions for a cheaper fix?

Merv; always best to start your own new thread ( post ) with a question that doesn't match the original poster's problem.
I think you should re-post your question in the Fleetwood section of the Owners forums. More people, who may have answers, will see it there.