GFCI Trips in Campground

[madjack]

...yeah and I don't care what any of ya got to say...play nice or I will lock this thread faster than you can spin in place...if you don't know what you are doing call a professional...if you want to get seriously technical...write a book!!!!!!!!!!!!!!!!!!!!!!!!!!
madjack

p.s. dulcimer bob...plug your trailer into a GFIC somewhere else...if it trips, you PROBABLY have a problem in your wiring, if it doesn't, the campground has a problem with theirs...some sort of circuit tester is advisable for any campground circuit you plug into...don't assume it's OK just because it is there...they may have had someone from here wire it up!!!!!!!!...MJ

[bobhenry]

[quote="madjack

...they may have had someone from here wire it up!!!!!!!!...MJ[/quote]

[wlooper89]

Madjack is right, but just when things were getting interesting. Darn! I think we are generally all on the same page, a few differences in terminology aside. The term "neutral" sounds so safe and benign. But would anyone want to grab hold of it standing barefoot on wet ground? The effect would be the same as touching the hot wire, without a GFCI around probably unhealthy. Anyway you all have me convinced to stay with the standard terms of hot and neutral in the future.

I accidentally switched the hot and neutral wires in one of the AC circuits in my teardrop. The lights still worked, appliances still worked. Only my little plug-in circuit tester said "this is not right". The mistake was easy to correct but it left me wondering about the circuit tester. "How do it know?"

Bill

[eamarquardt]

Play nice!! I agree But there are a lot of "half truths" spoken on this web site! Someone's gonna get hurt cause they don't understand what's not being said. Before I "play" with something new I consult all of the available resources, read, and discuss with people that KNOW.

As a result, I have all my fingers, toes, and few injuries to date. The only one who hasn't a minor boo boo is the one whose never picked up a tool (I understand such creatures do exist).

There should be no name calling on the site but sometimes I think BLUNT talk is appropriate!

Again, my favorite comment on this site is that an idividual removed a GFI because his tools kept tripping it! I have removed GFIs from circuits also, but only after consulting with the maker and learning that reefers are too inductive to work properly on GFIs.

Cheers,

Gus

[Dale M.]

Umm.... The neutral or common lead in most wiring situations (generally white wires on most wiring scenarios) is also tied to the safety ground (green wire or "U" shaped connector on receptical) at the entrance box in most residential and commercial installations and is usually usually that "bonding connection" is connected to a driven ground rod (earthed as the say across the pond) . ... This is US electrical code (law in most places when done right... And should carry through to travel trailer wiring..

So the "hot" or "energized" side ( black wire in most cases) should be isolated from the "common/neutral/safety ground"... Once that isolation path is compromised from a "IMPROPER" connection it should pop the GFI breaker....

Something as simple as having the hot/neutral wires switched at a appliance or receptical can cause GFI to pop... Or of course having your body across the circuit....

So bottom line is either shore power is wired wrong or trailer has wiring error... If your trailer causes GFI breaker to pop in every place you visit, the problem is yours (your trailer) if it only pops at one specific camp ground the problem is probably theirs....

Also as safety issue you trailer should be connected through a GFI breaker when hooked to SHORE power even at home....

Dale

[wlooper89]

Dale,

You post sounds good. If hot and neutral touch each other it will trip the circuit breaker because of overload. The GFCI sees this only as a load and may not trip, since it only detects a difference between hot and neutral wire amps.

Sometimes a GFCI and circuit breaker are combined. Some campgrounds may have this although I have not seen it and would be surprised they spent the extra money. But perhaps it is required by wiring code in some areas. The outlets for my garage use one of those in the home CB panel. If that trips it may be hard to tell what caused it, ground fault or overload. Allowing hot and neutral to touch creates an immediate overload.

Bill

[madjack]

....................................Also as safety issue you trailer should be connected through a GFI breaker when hooked to SHORE power even at home....

Dale

Dale, is correct in this...I have, as my main cord to hook up the trailer, a 12ga w/GFIC built into the male plug so as to always be hooked thru a GFIC...I also test it every time I hook up..........
madjack

p.s. I want everyone to be safe and informed...I just don't wanna see ANOTHER electrical thread fight over terminology...so I repeat...if you have no idea what you are doing, consult a professional...if you want to be technically correct in all aspects, get a code book and read it...or write your own............MJ

[mikeschn]

Can't one use one of those AC Receptacle Testers?

Something like this? We have one in the toolbox, in the teardrop!



Mike...

[wlooper89]

Powderburn,

Thank you for your kind words. I also use one of the circuit testers mentioned by Mike. It helped me fix a problem of switched hot and neutral on one of my circuits in the teardrop. Without the tester my trailer might still be wired that way. Now I keep it plugged in a spare outlet at my trailer switch panel.

Most of my electrical knowledge came from staying at a Holiday Inn Express. So it is really nice to hear from an electrical professional to help us sort out these questions.

Bill

[wlooper89]

Powderburn,

That is a great illustration of how a GFCI works. I am still trying to understand the concept of hot vs. neutral. Are they not equally dangerous if a person touches one or the other while the person is grounded? Perhaps my thinking is all wrong about this. For example I am lying on my back on damp ground under the house trying to fix something when I should have called an electrician. I am pretty sure touching a live hot wire could shock me. If I touch a live neutral wire, could it shock me? And would it make a difference if the neutral is connected to an air conditioner that is running?

As to the danger of being shocked by touching the hot wire and neutral at the same time, that seems pretty clear. It is something I have personally experienced a few times. Guess I am a slow learner.

Thanks! Bill

[atkryder]

AC theory is a very complicated thing to understand for some! The illustration is somewhat misleading! The neutral only needs the potential to carry the current it is not the true current carrying conductor!

[wlooper89]

Great stuff! I have learned a lot from this topic. Thanks everyone!

Bill

[eamarquardt]

Hi,
This is driving me crazy(er) so I drew a picture to show how power gets from the power transformer to your home. Note one of the high voltage feeds is grounded. There are three wires connecting the power company to your home. Two outside legs of a coil and a center tap. The center tap is what we call neutral as it (in your service panel) becomes joined to earth ground, thus it has no potentail to ground as the two are connected together making them the same potential. The two legs become the copper bars your circuit breakers make contact with. I've omitted the circuit breakers in the service panel as I'm not that good an artist (understatement). Note that the neutral buss and the ground buss are connected together in the panel. In a typical switched recepticle circuit (we'll keep it simple in this example) a white wire (neutral) a black wire (hot), and a ground wire (bare copper or green) are terminated as shown. I've put a switch in the ciruit so show that only the hot (black) is turned on and off. All of the current that leaves the service panel flows through the black, the load, and returns to the service panel on the neutral (it really flows both ways in a/c but it's easier to think of it flowing from the hot to the neutral). The ground wire is for safety only and under normal operation doesn't play any part (except to save your posterior if something goes wrong). If you look at the previous post of the GFI circuit these drawings are pretty much the same. You get 240 volts across the two legs of the secondary of the transfromer for your tig welder, mig welder, lathe and mill (converted to pseudo three phase-see album) and all your other 240 volt toys.



If anyone still has questions or is unclear send me a pm and I'll pm or email my phone or if you send your phone I'll call you and answer any question on "my dime".

There you have it, the world according to Gus

Cheers,

[eamarquardt]

I noticed my error as soon as I posted it and you were toooooo quick for me. I was fixing it as you were looking at it. It's right now (I think!).

Re the question about crawling under the house, being well grounded, and touching a hot versus neutral. Touching a hot will definately get your attention (or worse), in theory touching a neutral shouldn't be a problem. HOWEVER I wouldn't do it unless the circuit has been taken out of service (the breaker pulled) as you are betting YOUR LIFE.

Short of writing a book I've done my best to explain. If anyone is interested we'll start on 3 phase next and I'll explain how I got my 3 phase mill and 3 phase lathe to run on single phase (which I believe to be a confusing misnomer as it's really two phases 180 out of phase with one another when each is referenced to neutral) and the fine art of balancing the phases on a home built 3 phase converter.

Cheers,

Gus

[eamarquardt]

I can't remember how I wired the sub panel in my garage for all my toys. I may have connected the ground and neutrals! It was "inspected" but could have been missed. I'll check tomorrow and replace the failed light switch in my wifes office.

Never too old to learn, but too old none the less.

Thanks for the info on ground/neutral in subpanels. What is the name of the book you are getting your pictures from.

Cheers,

Gus