Converter issues

With a battery for the TT and no converter you should still be able to run the furnace and the other 12v things and being on shore power with 120v, the coffee pot and other 120v things too with no GFCI issues.

That's if the converter was the guilty party.

Not clear how you can measure zero output from the converter "pos and neg" but do get 20v DC across "pos and ground" The converter is "negative grounded" so that should not be possible unless there is a mix-up in terminology.

The converter 12v is grounded to the TT frame and so is the 120v shore power input. IE the 120v and the 12v share the same frame "ground" (It is not "Earth ground" but never mind that)

There is no connection between "positive" 12v and "hot" 120v but they share the frame "ground" BUT the 120v is between "hot" and "neutral" and 12v has no "neutral".

So how did the 120v GFCIs fry?

Thanks for all the input. Little more info. The converter actually has sticker labels someone put on it that was kind of confusing me as well. I pealed those of and got to the original labeling.
Here is what I have.
No DC output power from Pos to Neg.
~20.5v DC from Pos to Grnd.

I was trying to run the furnace when we heard crackling and it was the wall 110 outlet in the bathroom. Killed all power, removed the outlet & capped the AC wires with wire nuts. Turned on the power again and set for ~30 min. Nothing running, but all breakers on.
Then turned on the furnace & within 10 secs, heard the crackling again, this time it was the kitchen 110 outlet.
Killed all power and removed the converter because I notice I had no 12v working anywhere.

So, now that I know the DC converter has no output and the only time I had AC line problem was when I tried to fire up the furnace. I'm thinking the DC converter was doing something really weird & causing AC problems back through it's plug. I'm Thinking this because the furnace is only 12v and nothing else was plugged into AC anywhere.
With the converter out of the TT, the AC at the outlets is 111v and the outlets seem to be fine. Even plugged in a coffee pot to see if anything would wig. No change.

Thanks again for all the feedback.

GFCIs don't "fry" because of a GF, they switch off. They don't care if the DC voltage is 20v, they are 120v. Could the trailer have somehow got 240v?

The fridge 12v control board might be fried too. Norcold says 15.4v DC is the limit there.

Uh, Neutral is a 120vac side wire

Positive is a 12VDC side wire

The two should not be related so a "no reading" is normal though on shore power with the inverter connected things might be different,, You may also find a 60 volt difference between a 12 volt side and neutral on generator, But that is a false reading.

Converters come in several flavors, one is UNFLITERED and those can give a false voltage reading when not under load.

However that said, What is the make and model of your converter. Some of them needed upgrading the day they were put in the box at the factory.

It sounds like you have some general AC wiring problem. I find your descriptions are quite confusing, either because the problem is very confusing or because communication isn't happening.

The fried GFCI is IMHO most likely due to a bad connection on the line or load connections to it. I may be wrong, but that seems most logical to me. I would assume that the load line from it goes to other outlets or AC items, perhaps including the converter and/or fridge.

Maybe the fridge is misbehaving because the converter is producing an improper voltage? Do you have a good 12V battery hooked up—and if so, have you verified that it is still good?

At any rate, it may or may not be that your converter is fried, and/or that you have other wiring problems in the trailer. If it were mine, I would be hesitant to use the 120V electrical system until I (or somebody else who was qualified) understood what was going on and had fixed the underlying problem(s). I'm not fond of potential/possible electrical fires.

gsf35099 wrote:
Anyone ever seen a converter cause an AC issue like shorting out the GFCI?

My 30 amp converter has no output between the positive & neutral & 20 volts between positive & ground. Thing my converter is fried.
I was running my TT off a generator and only running the heater (12v & propane). Then the refrigerator started to turn itself on. I would turn the frig off & it would turn itself back on. Then we noticed a burning smell & poor the GFCI outlet in the bathroom fried. Pulled it out and removed it after killing the power. Applied power again with nothing running & everything was fine. Turned on only the heater again and the GFCI outlet in the kitchen started to fry. That is when I removed the converter and started measuring.

Very confusing.

You seem to be describing a "three pronged" 120v receptacle where HN voltage is zero and HG is 20v AC? Where are you measuring these exactly and what units is the meter switched to?

Or are you getting 20v DC on the 12v system?

A converter is plugged into 120v AC and makes 13.x volts DC. It is part of the Power Centre that is 30a AC capacity with some circuit breakers in its AC panel. It could be the cause or it could be a victim or it might be fine once the language/definitions are clarified here.

More likely your shore power cord plug or its adapter is faulty where plugged into the generator. The generator may have one of those "bonding" things going on that gets confusing :(

By "heater" do you mean "furnace"? The fridge coming on by itself--is it in "auto" or gas or just AC? Did it come on under 12v or 120v?

09FLSTC wrote:
There shouldn't be output between hot and neutral. That is input. 20 volts output from the pos and neg DC is way too much. What is the model of your converter. Bestconverter has likely heard your scenerio before and well regarded and knowledgeable to get you pointed in the right direction. I know this, I would not run my RV from a generator without a surge protector and that could have been part of all of the problem.

X2.
Time for a nice new 3 stage converter.

There shouldn't be output between hot and neutral. That is input. 20 volts output from the pos and neg DC is way too much. What is the model of your converter. Bestconverter has likely heard your scenerio before and well regarded and knowledgeable to get you pointed in the right direction. I know this, I would not run my RV from a generator without a surge protector and that could have been part of all of the problem.