Shore power suddenly trips breakers

[MinnesotaTom]

Sent: 7/24/2008 3:01 PM

Hi Guys,

Sunny has a new trick she wants to demonstrate! BAADDDD Sunnybago!  It's electrical.

Let me lay out what I've done: You will recall she came with the roof air that had never been reconnected after the roof rebuild by the PO. Been so busy (and it hasn't been that hot here, so I pushed playing with the unit to the back burner...until we had a torrential downpour and.....it leaked a little. Seeing as I have a new roof and ceiling this understandably caused me a bit of concern... (translated: oh, S%^$!!!!). NOW the roof air became a priority. I suspected it was junk anyhow, but decided to test it before junking it and filling the hole with a pop-open screen vent with a fan. I dropped the cover and control box from where it was tucked up out of the way, stretched the wire from where it was tucked inside the cabinet, connected it, plugged in shore power, and was rewarded with a smooth blast of cold air that got the interior nice and cool in a short spell. EXCELLENT!   Parked her out front where she leans away from the leaking edge of the unit in case it rained before I could get back to it.

Yesterday I got to work. Ended up pulling the entire unit and resealing it with caulking cord, then tying it back down (fashioning a fourth tie down to replace the missing/broken one on the corner where it leaked). It passed the hose test, so we'll keep our fingers crossed. Then the problem started, the electrical one....

There's a piece of romex (standard white jacket 3 conductor house wire) inside the cabinet above the sink meant to fire the roof air. Same piece I tested it with. It's hot as soon as the shore power is plugged in. I ran it through a 1/2" piece of white pvc for appearance sake, boring a hole in the cabinet and another in the unit cover, then set the cover aside. I got the control box mounted, connected the wires, and hooked up to shore power as I did before. "ZAP"! Breaker tripped in the house. I disconnected the entire roof air, all three wires. "ZAP"! ^&%$! Maybe it's the 30 amp(?) adapter? No, that worked fine before and I had the a/c unit running long enough to pool water on the roof (also made a drain hose yesterday while it was out) . But, there's NOTHING turned on! I can't get shore power!  Weirder still....the deep cycle battery seemed to be dead. Flipping the switch on the inverter from 110v to battery had no effect, no lights, no 12v systems.  I went inside, had something to drink, and returned....to find the reading light on over the bunk. I had inadvertently left the switch set on "battery" and somehow it "reset" itself. I had tried pushing the circuit breakers and circuit protector buttons earlier to no avail.... Hmmmmm. I tried to turn on a ceiling light.....and the reading light went out.....the system was dead again!

So, to recap: I have no shore power even with the roof air completely disconnected. Worse, I seem to have no 12v system. Two systems I never had problems with before. They worked fine when we camped two weeks ago, plus the shore power was fine last week. Ideas? I'm about  to start disconnecting things trying to isolate the problem.

Minnesota Tom

[olhillbilly31]

Sent: 7/28/2008

now i live in a little old 1981 mobile home... my Southwind was doing the same thing.. turn on the ac and trip a breaker in the house. i had to try almost every plug in the house before i finally found a breaker that wouldn't trip.. mainly the only thing on that breaker is the refrigerator, and the stove.. now my breakers are like 15 amp or something like that, i really need to put in a bigger breaker and a plug in just for the motor home.. i have noticed that the extension cord cord from the motor home tend to get hot, i can live with it for now, if i still have the motor home this fall i will have a new breaker installed in the house when i start remodeling it..

[denisondc]

Sent: 7/28/2008

The problem with installing breakers with a larger rating than your original 15 amp ones, is that the wires buried in the wall don't get any bigger. They are probably awg 14, and more than 15 amps will make them get toasty warm when 'concealed' in a wall. Just putting in new 15 amps breakers, and snugging up all of the connections and screw clamps can eliminate some problems. Breakers don't necessarily last forever.
To plug in our motorhome down in Texas, I ran a new circuit from the main breaker panel, using new 10 gauge UF housewire, not the usual 12 gauge. I fed it with a new 20 amp breaker, and used a 20 amp duplex outlet of better than average quality, in a waterproof outlet box.

[olhillbilly31]

Sent: 7/29/2008

yeah thats what i was going to do..lol i was typing while tired and forgot to add that part.. new beaker, new wire, pulh in just for rv..lol

bily