30 AMP shore power tripping

[Ronjames]

Our 2004 Puma is on a permanent site at the campground and we stay plugged in to the 30 Amp pedestal on the site. Never a problem for the year we've done this. Yesterday, we plugged in a electric skillet to the outside receptacle on the camper. Since we had the AC running and everything but the microwave I was just about to say "we should probably run this skillet straight from the 20amp on the pedestal." I never even got the words out and then POOF! Everything shut down. I checked the breakers and fuses on the trailer's power converter, but they did not trip. I checked the pedestal 30amp breaker and it was tripped. With everything turned off and unlplugged in the camper, I reset the breaker. but it would not reset. it was an immediate trip. I swapped my shore power cable to the adjacent site to see if maybe the breaker was bad on my site's pedestal. But nope, it tripped immediately. All breakers and fuses in my Parallax Power 7300 checked out good. SO...could it be that I smoked something in my Parallax 7300? I would have thought if that was the case I would have tripped the camper's breakers. Any helpful thoughts would be appreciated.

[bartlettj]

Ronjames wrote:
It was the shore power plug. Melted wire created a short.

I had this happen on a 240V/5HP air compressor when I plugged it in to my 50A garage outlet, and it arced so hard it blew the main panel breaker too. The arc was really bright, and then the entire garage went dark. I thought I had blinded myself. Now I always flip the breaker before plugging in.

[enblethen]

Thanks for the update!

[Ronjames]

Thanks everyone. If i figure how to post a pictures i will.

[Ronjames]

It was the shore power plug. Melted wire created a short.

[ScottG]

The Parallax could easily be the problem.
When they fail, they can create a tremendous short. I would flip the main breaker in the RV's panel and then try plugging in. Then you'll know if it's the power cord itself or soemthing in the trailer.

[wa8yxm]

The Parallex was very likely unaffected, But you clearly have a problem somewhere.

As the other reply said Turn off ALL Breakers, Then see if it still instant trips.. If it does you have a short in your cord or lug.. I came close to that (Had an open in the plug) 2 weeks ago but fixed it.

Then turn on the main.. Still no trip? good,

Turn on ONE branch, then the next, then the next

If you can make the first branch something you can plug a lamp into Turn lamp on.. Light is good

now one at a time turn on other breakers, when the lamp goes dark.. You found it.

[enblethen]

The converter is just another type of appliance. 120 volt system should operate even if the converter does not.
Bad cord body could be issue, but try first shutting off all breakers applying light pressure toward off. Then turn on main breaker if equipped followed by branch breakers one at a time.
Do not believe breakers are issue. More like a wired burnt off in the 120 volt section or a destroyed GFCI receptacle that feeds the exterior receptacle.

[Ronjames]

Thanks guys. We bugged out of there last night anyway because of severe thunderstorm warning and our power problems but I'm going to run back there this afternoon and check things out again when I'm not in a rush like yesterday. I'll post whatever I figure out.

[MEXICOWANDERER]

It would help to do a systematic check.

I have seen shore power cords short internally so you might want to just plug that in by itself. It means shutting off the main breaker and all other breakers in the rig.

If successful no tripping.

Shut off not only all other rig breakers but shut down appliances and things plugged in.

Then progressively start and then shut off each breaker.

Then load breakers by switching on, one-by-one

Then enable plug-in loads one-by-one

What do you see?

[Ronjames]

No transfer switch. I'll go back up and recheck with camper breakers off. I guess if it trips with all my breakers off maybe it's the dang plug or cable. Would it be correct to say the 110 outlet circuits run directly from the camper breaker panel without regard to the converter?

[dfletch]

if you have a transfer switch it is usually between the RV main breaker and the campground breaker. If shorted out it would cause this.

[sch911]

Shut off all off for breakers. Does it still trip?

If not Bring each circuit back until you find the culprit.

Oh and don't forget the electric water heater.