Electrical Short

[Ldeal3650]

I recently noted an "AC Overload" message on my inverter and was able to track the problem down to a short in the wiring in my door side slideout in the living room. Surprisingly no circuit breakers tripped.

I have a 2013 Montana 3625RE. The shorted wired runs from the rear desk outlet (Door Side) into the wall lamp in the center of the slideout (Door Side). The cables are tight on both ends so pulling it through with a new one is not an option. Does anyone have any ideas on how I can identify how the wire is routed and how best to fix the problem. Any suggestions would be greatly appreciated.

Len in Key West

[Ozz]

Len, I see you are in Key West, I am so Jealous I don't know if I can feel sorry for your problem.. Just kidding, it is always a pain to have electrical problems.
I am a bit confused.. which is normal, but other than the Inverter showing AC Overload.. do you mean converter? I am not familiar with that feature.
Are any loads not energized? Lamp doesn't work? How does the short manifest itself? I am surprised the short does not trip a breaker as well.
In the past, some of us have had problems with a connection; a 2x4 box with cover under the slide, that has poor connections, you can pull the cover and check them.
All of the problems listed are very conflicting and confusing to me, but try that box for bad wires.

[Ldeal3650]

I tried looking under the slide but could see no 2X4 boxes.

I have a 2000 Watt Magna Sine inverter added as part of a Solar package.

To clarify a bit. When I turn on the inverter which powers the circuits in the living room (Door Side) slide I see a rising amperage to 105 amps or thereabouts then the red lite on the inverter with a message "AC Overload". No breakers tripped. When I switch off all breakers no "AC Overload". Then I switch on the breakers one at a time and all is fine until I switch on the breaker which controls the side lamp and rear outlet. The current rises to 105 amps an I get the lite.

Upon checking each wire (with the circuit breaker switched off) i found a short between the black and the bare wire. It was in the wire from my rear desk outlet to the AC wall lamp in the center of the slideout. Hope this clarifies some.

I'll look some more for the box you mentioned. Thanks.

[mhs4771]

OK, forget everything I've posted below, seems you were adding additional info at the same time. As mentioned, you need to see if you can find a junction box under the slide.

OK, I have to make a couple of assumptions here. I would assume that you've had an after market Inverter (converts 12VDC to 115VAC) added to your system to supply 115VAC power to some specific outlets when BoonDocking. If that is the case, the message about "OverLoad" would indicate you had more things running and drawing power than the Inverter could supply, because if you really had a "Short" the Inverter should shutdown immediately.
What is the rating on said Inverter and how many outlets is it wired too??

[Ozz]

I see now, good job of troubleshooting, it looks as if you are no stranger to problem solving.

[Ldeal3650]

It is a Magna Sine 2000W inverter and it indicates and "AC Overload" shortly after switching on the CB controlling the Door Side living room outlets. It does this even when no loads are attached.

Disconnecting each outlet and lamp and checking each wire for continuity revealed the short between black and copper wires on the run between the rear desk and the wall lamp on the slideout. Hope this help clarify things.

Len

[jimcol]

If I interpret right you do not have a short but the hot is going to ground. That's why it's not popping the breaker but does set up a constant current flow which could be over driving your inverter. Remove the wiring from both the A/C outlet and the wall lamp or lamps. These wall lamps and switches have been notorious for defects and corrosion. If the fault is still there you'll have to find a junction box or conclude it is in the hardwiring inside the wall. Good luck and let us know what you find. Jim

[WaltBennett]

jimcol is right. Hot going to neutral (return, or white to black) would cause a breaker to pop. Hot to ground wouldn't.

[NCFischers]

Any hot to ground will cause a dead short.

[K0LCB]

Jim, I think earth ground and electrical neutral on RV 50 amp plugs are separate, unlike house 220 circuits, JMHO

[NCFischers]

On house main panels and campground main panels, the ground and neutral wires are terminated on the same buss bar. Because of this, you will cause a dead short if a hot wire comes in contact with a ground wire. Newer 220 circuits in houses, dryer circuits for example, have both neutral and ground wires.

[DQDick]

Jim's the man when it comes to electrical knowledge.

[Ozz]

quote:Originally posted by DQDick

Jim's the man when it comes to electrical knowledge.

Yes, he is, a nice man as well Jim owns an electrical contracting business, toying with retirement, teasing it a bit I think.....

[Ldeal3650]

Found the problem in a connector in the back of the coach near the DS slideout. Connector was all burnt so I'm convinced that is the problem. Thanks for all the helpful posts. Much appreciated.

Len

[Ozz]

Glad you found it Len, sometimes they can be a real headache. Now down to Sloppy Joes for your reward for a job well done..

[Samiterry]

Jim and Ozz, wouldn't you agree that if there was some melting going on that there was some sort of resistance thereby eliminating the dead short to ground and instead show a very high amperage display on his inverter without tripping a breaker ?

And as a side note : Len, I think you're lucky there wasn't a fire.

[Ozz]

I have seem many wire nut connections' plastic melt because of loose connections, service disconnects with melted insulation on the wires to the disconnect also. Resistance heat which would show up as amp draw. But, I am not familiar with the operation and sensitivity of the Inverter. One.. me.. would not think it would alarm with that bad connection. If it was on a 15 amp breaker, which it probably was, it just wasn't pulling 15 amps, or reacting to a dead short.
I am not an expert by any means, but that is my take on it. It would be helpful If I saw the connection so I could tell more about it. We all are at a dis-advantage not seeing it.
So.. I think I agree with you

It certainly wasn't as bad as this one I repaired

[jimcol]

Jim, You certainly know a lot more about this then I do. I agree any hot directly wired to ground is a dead short. I have seen a hot going to ground with some resistance in it like in a junction box with poor connectors that just sits there and heats up the wire and or connector. (we use to call them high shorts) The breaker won't trip until the amp draw exceeds the rating of the breaker. Since the OP's breaker wasn't operating I was just pointing out he may have a resistive short to ground causing a high draw on his inverter. Based on what the OP found and Ozz's and Samiterry explanation I would guess that is exactly what was happening. Jim

quote:Originally posted by NCFischers

Any hot to ground will cause a dead short.

[Ozz]

I was just trying to demonstrate a current draw caused by loose wires, like an electric heater in miniature, not current to ground.

[7.3Ford]

Len,

It sounds like the found the problem, since you have a 2000 Watt Inverter (that is surge rating more than likely) and continuous output is around 13.7 AMPS, so under the breaker pop. You are very lucky it didn't catch on fire.

It sounds like there was enough resistance so it wasn't a direct short (which would really have been better in this case, since the breaker would more than likely have blown). Jim is right on the money as far as short goes.