GFCI Trips in Campground

[BPFox]

Since this discusion is winding down now I promise not to stir the pot too much. There has been some confusion in these discussions and I think I can help clear some of that up. Like I have stated many times in the past, the use of certain terms can cause a lot of this confusion. Example the use of the term "common" or "neutral" to describe the "white" wire in most 120 v ac wiring. No need to argue that "my term" is better than "your term" here. They both work, they both are correct.

Alternating current needs to flow back and forth through a completed circuit to work. The "white" wire serves that purpose. When the circuit is complete, current flows through both the "white" wire and the "black' wire. The same amount of current is flowing through both. That said, don't ever confuse the two. When the circuit is not complete, they are both very different and mixing them up can be dangerous.

If you think the use of the term "neutral" is confusing, think of it this way. Let's say the "white" wire is like a transmission that is in "neutral". The engine is running and that represents the power coming in from the source. (could be the campground, could be the power pole at home, could be a generator) The pilot shaft in the transmission represent the "hot" lead or black wires. As long as the "neutral" wire stays in "neutral" the car goes no place. The engine is still running and the pilot shaft inside the transmisison is still turning, but the car goes no where. Once you "switch" the transmission from "neutral" to your chosen gear (just like turning on a light switch) the car moves.

Now let's look at the term "common". The reason this term is used is because all of the "white" wires are "common" to each other. They all terminate at a "common" point in the panel. They are all wired to a "common" point in the electrical system. They are basically "hooked together" to provide one common path back to the panel. The "hot" wires on the other hand take individual and separate paths back to the panel and serve to separate the circuits. Each circuit is controled by the "hot" wire. This is why you only interupt the "hot" lead. Never interupt the "common" or "neutral" lead.

So yes Virginia, if your circuits are wired correctly you can touch that white wire and not so much as feel a tingle. This is where the big "if" gets in the way. It's probably not safe to try this at home kids. All it takes in one "white" wire on a "gold" screw for the results of this test to get quite shocking.

Now your electricity will work just fine with just a two wire system. Most homes only had a two wire system for years. The "green" wire came later and it's just an "alternate" route for the electicity to travel on if something happens to the "white" wire. In a perfect world, the green wire will never see one electron flowing through it. Heck, most of the time it won't even have something plugged into it. The idea behind the "green" wire is to provide an alternate path for stray voltage. Before the "green" wire came into play, often times that altenate path came in the form of a human being. Since the human body will conduct electricity, and electicity always wants to go home to mother earth, it will seek the path of least resistance. Since it is easier for electricity to flow through you than it can through, let's say air, it will choose to go through you. The green wire, on the other hand, provides a better path for the electricity so it will choose that route instead. This is where the safety part comes in.

Now we have an even better system. The gound fault circuit interupter. This is way better than a simple ground wire since it shuts the power off. Instead of just providing an alternate route for the flow of the electicity, it shuts the power off.

The bottom line here is that it is very important to know and understand the function of each wire. They are not the same even though at times they might be performing the same task. Not knowing the difference can be deadly. Peace.

[eamarquardt]

I think we've said the same thing, but I like your analagy to "neutral". Never touch a wire unless you've verified (with some device) it's out of service or you're playing "You Bet Your Life".

Cheers,

Gus

[eamarquardt]

Went to visit #1 son at Cal Poly SLO where he is somewhere on the road to a degree in ME not EE. We're not sure of the cross street just yet! Anyway we were having a sandwich at one of his favorite haunts and I looked up at the transformer on the telephone (or power, your choice) pole and the difference in the size of the input conductors and the output conductors was clearly visible to the naked eye (I can see ok at a distance still). I asked him why were the output conductors so much bigger given that the power into the transformer and out of the transformer were roughly the same. His response:

pv=nrt

I just laughed and asked him what that had to do with it! Apparently he didn't pay close enough attention when he took physics!

Cheers,

Gus

[madjack]

...manymanymany years ago(I was just a kid)(in the days before the "green" wire), I went with my Dad to help change out a well pump at one of his friends camp...flipped the breaker, checked the power and it was off..my Dad touched the pipe coming out of the ground to the pump and was knocked to his knees...checked with meter and power was dead to the pump and the breaker was definitely off...turned out that the pump motor had been wired backwards with the black to "common"(or ground) and the white to the breaker...even at 12, I learned an important lesson that day...which wire goes where is VERY IMPORTANT..........
madjack

[cokebottle10]

Boy I sure have enjoyed reading this. I just can't stay out any longer. You guys have covered the hot, common, ground, black, white and green well enough. I do not need to add anything.

As to help answer the post. If this is happening at all the GFCIs. I would say look for a common (white) wire touching ground (green or bare) wire or the frame. Look for moisture also. First off unplug everything. Then switch off all the breakers or pull the fuses. Then plug in the trailer. If it trips then the problem is from the GFCI to the distribution box (fuse/breaker box). If it does not then start turning on one circuit at a time until it trips. If you get all the circuits on without triping the GFCI then start pluging in things one at a time and turning them on. This should get you a location of the problem.

Please fix this. If you do not then if for some reason the common comes loose or has a bad connection you could electrify the whole trailer. Much like Madjacks pump.

If this only happened in one place then it was most likely a bad GFCI.

I hope this helps.

David