Grounding Your Camper

Anything electric, AC or DC

Postby Larwyn » Wed Mar 22, 2006 6:16 am

Seems to me that a person or object in contact with earth/ground which also comes in contact with the live wire would cause sufficient differential current to trip the GFCI.
Larwyn

Keeper of the Most Out Of Control Shop (2005)

I feel bad for the man that cannot spell a word more than one way. Mark Twain
User avatar
Larwyn
Mad Kilted Texan
 
Posts: 1658
Images: 210
Joined: Sun Jun 20, 2004 12:06 pm
Location: Kerrville, Texas

Postby Mullet » Wed Mar 22, 2006 6:21 am

Miriam C. wrote: or use battery powered everything. *(D cell type)

Miriam


This is so true. I pulled everything out of the back of my O'Day 25 so that i could repaint the interior. Instead of removing one thing at a time, and taking it to the ground, I put everthing in the cockpit, first, and then started my trips up and down the ladder, unloading the boat. I got tired of ducking under the mast (boat was on the trailer and the mast was down), so I slid the mast over to one side, out of the way, and continued unloading things from the cockpit.

Unfortunately, I didn't notice that when I slid the mast out of the way, the backstay fell off the sternpulpit and into the cockpit (i.e., one of the wires that holds the mast upright fell off the railing that goes around the back of the boat). Eventually the backstay completed the circuit on my battery and starting a plastic bag on fire. The battery still works great, but the backstay was toast.

Make sure your electrical is up to spec or make your tear out of masonry: it took my 12v battery just a few seconds to get a 5/32" cable RED hot.
Mullet
Teardrop Inspector
 
Posts: 7
Joined: Fri Mar 03, 2006 7:43 am

Postby GeorgeTelford » Wed Mar 22, 2006 6:40 am

Larwyn wrote:Seems to me that a person or object in contact with earth/ground which also comes in contact with the live wire would cause sufficient differential current to trip the GFCI.


Hi Larwyn

Yes but note some people are advocating that no earth or ground is needed to set of an RCD (GFCI)
User avatar
GeorgeTelford
500 Club
 
Posts: 677
Joined: Mon Jul 11, 2005 2:10 pm
Top

Postby angib » Wed Mar 22, 2006 7:48 am

GeorgeTelford wrote:The difference between live and neutral is what springs the GFCI (RCD) but if there is no earth/ground present then the GFCI will never ever trip, it cannot

Yup, a serious problem when camping in mid-air. Do you do that a lot? :lol:

Yes, you need an earth/ground to short to, in order to trip a GFCI. No, it does not have to be an earth/ground wire - the real earth or ground the trailer is sitting on will do just fine, if it is conductive.

Andrew
User avatar
angib
5000 Club
5000 Club
 
Posts: 5783
Images: 231
Joined: Fri Apr 30, 2004 2:04 pm
Location: (Olde) England
Top

Postby GeorgeTelford » Wed Mar 22, 2006 8:16 am

Hi Andrew



Yes very funny, but it as been suggested here that metalwork and the chassis etc not be bonded to the earth wire or to the Ground beneath, so in effect you would be camping in mid air. It also means under fault conditions the chassis and bodywork can become live and NOT trip the RCD (GFCI)

Using that yellow portable unit is the same, its increasing the risk of being killed, there is no proper way to bond the conductive material of the camper to earth, its not meant for use in a camper.
User avatar
GeorgeTelford
500 Club
 
Posts: 677
Joined: Mon Jul 11, 2005 2:10 pm
Top

Postby Endo » Wed Mar 22, 2006 8:32 am

GeorgeTelford wrote:Using that yellow portable unit is the same, its increasing the risk of being killed, there is no proper way to bond the conductive material of the camper to earth, its not meant for use in a camper.


Please explain. If the yellow portable unit is plugged into a properly grounded outlet (which you have already tested with your outlet tester) isn't it already earth grounded???

If that is not correct then this outlet is never properly grounded whether it is used in a camper or not.

It doesn't seem any different to tent camping and plugging in an extension cord/yellow box for power.

My yellow box is mounted to wood. I don't have any 115V wire running through or touching any metal at all on my trailer. Where is the risk of a short??

I do want to make sure it is safe and I'm not missing something.
Last edited by Endo on Wed Mar 22, 2006 2:46 pm, edited 1 time in total.
Brad (aka Endo)
ImageImage Image
In God We Trust
User avatar
Endo
500 Club
 
Posts: 721
Images: 138
Joined: Fri Apr 01, 2005 9:59 am
Location: Ohio
Top

Postby bdosborn » Wed Mar 22, 2006 9:42 am

GeorgeTelford wrote:Hi Bruce

You are completely and utterly wrong.



Nope, I'm not. I'm completely and utterly correct.
http://www.ecmweb.com/mag/electric_gfci ... index.html
Bruce
Last edited by bdosborn on Wed Mar 22, 2006 10:01 am, edited 3 times in total.
2009 6.5'X11' TTT - Boxcar
All it takes is a speck of faith and a few kilowatts of sweat and grace.
Image
Boxcar Build
aVANger Build
User avatar
bdosborn
Donating Member
 
Posts: 5492
Images: 767
Joined: Wed May 05, 2004 11:10 pm
Location: CO, Littleton
Top

Postby bdosborn » Wed Mar 22, 2006 9:46 am

Larwyn wrote:Seems to me that a person or object in contact with earth/ground which also comes in contact with the live wire would cause sufficient differential current to trip the GFCI.


Bingo!

Bruce
2009 6.5'X11' TTT - Boxcar
All it takes is a speck of faith and a few kilowatts of sweat and grace.
Image
Boxcar Build
aVANger Build
User avatar
bdosborn
Donating Member
 
Posts: 5492
Images: 767
Joined: Wed May 05, 2004 11:10 pm
Location: CO, Littleton
Top

Postby Jim Marshall » Wed Mar 22, 2006 11:13 am

This has been some very interesting and useful information but somewhat confusing. We are using straight 110v in our tear for all our electrical devices, like I stated in the first post. I don't see how the wires can come in contact with the aluminum skin and for sure not the trailer because of the way the wires are run. I can see how maybe a screw can break the insulation to one of the hot wires, making the skin live, and there is always that chance. I do know where the wires are and have stayed away from them with the screws but still there is a chance that my memory may have failed. My original question was, should I run a ground wire to the aluminum skin?

At this point, I plan to have a circuit breaker in a box and all GFCI receptacles with a ground wire connected to our skin and maybe even the trailer. Is this the proper way to be safe? Like I said in my first post, I have had my lamp lite when camping and it was no fun.
I started out with nothing and I still got plenty left.

VOL-N-TEAR
User avatar
Jim Marshall
The 300 Club
 
Posts: 343
Images: 63
Joined: Wed Sep 28, 2005 12:31 pm
Location: Chattanooga, Tennessee
Top

Postby GeorgeTelford » Wed Mar 22, 2006 12:13 pm

Hi Bruce

The link you posted shows exactly why you are totaly and utterly wrong.

The earth in the link is the ground beneath our feet, but you have already suggested using mains in a tear with no earth wire bonding or path to ground.

Remember saying that the yellow outdoor extension was a good idea? and now you can see why it isnt, No ground path in tear and or earth wire bonding.

Have we a real American electrician here, to explain it to Bruce? Its against regs over here and against code over there and an unecessesary danger anywhere.

Jim

Thats the way to go, you had your lamp lit because of wrong wiring in the first place, which is exactly what the dont earth brigade are suggesting that you should do again.

If its all earthed and bonded, if any current gets to skin it would trip RCD before you got there.
User avatar
GeorgeTelford
500 Club
 
Posts: 677
Joined: Mon Jul 11, 2005 2:10 pm
Top

Postby bdosborn » Wed Mar 22, 2006 12:15 pm

Jim,

Sorry, these electrical questions tend to get bogged down in technical arguements. That's why I should keep my mouth shut. But FWIW, my opinion is that you should ground the frame and you should ground the metal skin, for all the reasons discussed above. A live wire may never, ever come in contact with the skin but a wire to ground it is cheap and easy and it should keep you from being lit up.
Bruce
2009 6.5'X11' TTT - Boxcar
All it takes is a speck of faith and a few kilowatts of sweat and grace.
Image
Boxcar Build
aVANger Build
User avatar
bdosborn
Donating Member
 
Posts: 5492
Images: 767
Joined: Wed May 05, 2004 11:10 pm
Location: CO, Littleton
Top

Postby GeorgeTelford » Wed Mar 22, 2006 12:18 pm

Hi

Just a quote from the linked site to reinforce what I am saying

However, a GFCI doesn't give you a license to be careless. Severe electric shock or death can occur if you touch the hot and neutral conductors in a GFCI-protected circuit at the same time because the current transformer within the protection device won't sense an imbalance between the departing and returning current and the switching contacts will remain closed.

Note the bold bit, if there is no earthing and bonding in your tear, you are likely to die in a fault situation.
User avatar
GeorgeTelford
500 Club
 
Posts: 677
Joined: Mon Jul 11, 2005 2:10 pm
Top

Postby Jim Marshall » Wed Mar 22, 2006 12:27 pm

Thanks fellows, I really do appreciate this information, I feel comfortable now knowing that no one will get zaped from our camper. :thumbsup:
I started out with nothing and I still got plenty left.

VOL-N-TEAR
User avatar
Jim Marshall
The 300 Club
 
Posts: 343
Images: 63
Joined: Wed Sep 28, 2005 12:31 pm
Location: Chattanooga, Tennessee
Top

Postby bdosborn » Wed Mar 22, 2006 12:35 pm

GeorgeTelford wrote:Hi Bruce

The link you posted shows exactly why you are totaly and utterly wrong.

The earth in the link is the ground beneath our feet, but you have already suggested using mains in a tear with no earth wire bonding or path to ground.

Remember saying that the yellow outdoor extension was a good idea? and now you can see why it isnt, No ground path in tear and or earth wire bonding.

Have we a real American electrician here, to explain it to Bruce? Its against regs over here and against code over there and an unecessesary danger anywhere.

George,

I think you need to reread my posts. I never advocated not using a ground wire. I simply stated that a ground wire is not neccessary for a GFCI to work. It might be a good idea for you to quote my posts so we can discuss specific items if you disagree with them. If you do a forum search you'll see that I posted quotes from the NEC requirements for trailer grounding so I'm aware of what is required by code.

And by the way, your'e speaking to a real American Electrical Engineer. I don't think an electrician will be neccessary.
Bruce
2009 6.5'X11' TTT - Boxcar
All it takes is a speck of faith and a few kilowatts of sweat and grace.
Image
Boxcar Build
aVANger Build
User avatar
bdosborn
Donating Member
 
Posts: 5492
Images: 767
Joined: Wed May 05, 2004 11:10 pm
Location: CO, Littleton
Top

Postby rampage » Wed Mar 22, 2006 1:25 pm

Wow, this thread is giving me a headache. :? :? :lol:
"If you can't be a good example, then you'll just have to be a horrible warning"
User avatar
rampage
Donating Member
 
Posts: 286
Images: 5
Joined: Tue Jan 24, 2006 12:02 pm
Location: Florida
Top

PreviousNext

Return to Electrical Secrets

Who is online

Users browsing this forum: No registered users and 7 guests