Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-01-2004, 05:19 AM   #1
Very american 4 a french
 
brunoffrance's Avatar
 
1971 27' Overlander
DUNKERQUE / FRANCE , Nord
Join Date: Nov 2002
Posts: 633
Images: 68
Blog Entries: 9
Wiring to the ground ?

Hi there ,
After 2 monthes, in Campgrounds, the holiday season is finished...
the weather was not good , particulary near my home, in the north of FRANCE, where I've decided to live in my A/S and work in the same time, during summer. So what a stormy weather and people and i, wondered if the caravan has to be in contact with the earth ground with a wire or a cable, just in case of the storm flashed me...

Do you plug the caravan to the ground ?
Is there an original cable on genuine A/S to put on the ground , how it was and what to do; may be these complete the electrical wiring, to run well ?

just tell me what to do to secure the caravan.

Thank you by advance.

Bruno.
brunoffrance is offline   Reply With Quote
Old 09-01-2004, 05:32 AM   #2
Retired Moderator
 
john hd's Avatar
 
1992 29' Excella
madison , Wisconsin
Join Date: Aug 2002
Posts: 4,644
Images: 40
bruno

yes and no

your trailer should be grounded through the electrical service. knowing that you use a transformer in europe to convert 220v to 110v, may create additional connections to earth.

you can add a ground wire from the frame of the trailer to a driven ground rod if you plan on leaving the trailer in one place for a long time.

this would help protect your step down transformer from lightning by providing a direct path to ground instead of having to travel thruough the transformer.

you can accomplish this simply by driving an 8 foot ground rod straight down and attaching it to the frame of the trailer with #4 awg wire (about 1/4 inch diameter wire). clamp the other end to the trailer frame, clean the connection point to bare shiney metal and use a non corrosive clamp such as bronze or stainless steel.

good luck with your project.

john
__________________
you call them ferrets, i call them weasels.
john hd is offline   Reply With Quote
Old 09-01-2004, 08:48 AM   #3
3 Rivet Member
 
Join Date: Oct 2003
Posts: 132
Images: 2
John, good answers!

I'd like to point out that most trailers are properly grounded when the tongue jack is solidly 'grounded' to the ground surface. However, most of us install a non-metallic object between the turf and the tongue jack that prevents proper grounding.

John, the solution you mention is a good solution to what a lot of us do. I, however, use the Airstream tongue jack plate that is made from aluminum and completes the grounding process through the tongue jack.

Rick
Rick Alston is offline   Reply With Quote
Old 09-01-2004, 11:53 AM   #4
4 Rivet Member
 
dtbw's Avatar
 
1999 34' Limited
2002 19' Bambi
Allen , Texas
Join Date: Apr 2003
Posts: 292
Images: 15
Not such a good ground

Rick,
The jack post/pad is not a reliable grounding mechanism for a variety of reasons. The first is that the path from the trailer 120v electrical system ground, to the trailer frame, to the jack to earth is typically not electrically solid. The connection points between the jack and the frame tend to corrode over time which causes there to be some resistance and the connection between the frame and the trailer 120v ground point can also develop rust or corrosion. In many campgrounds, the area under that jack is either asphalt, concrete or loose gravel which effectively INSULATE the jack from any potential earth (ie damp dirt) contact.

Although most of us don't do it (me included and I know better), a 1/2' copper rod should be driven into the ground at least a foot or so (watered regularly to ensure contact) and attached to the trailer 120V ground connection located at the circuit breaker box. A/S does attach wiring from this connection to the frame, but again, the state of that connection varies as the trailer ages and is exposed to weathering. On later model A/Ss, there is a wiring lug strip where the 12v negative, the 120V earth ground, the connection to the frame along with the wire to the 120v circuit breaker box earth ground are joined together. There are typically additional openings in the lug strip where you can install another wire which could be run to the outside for connecting to a true earth ground.

Depending on campground power for earth ground is at best iffy. If you can measure ANY voltage potential between neutral and ground with a digital multimeter, that means that the ground connection is NOT truly grounded (something I find at LOTS of campgrounds). A few millivolts is normal, but when you find more than a few volts, then the earth ground connection is faulty within the park power.

On the matter of lighting protection, I installed both a 12v and a separate 120V surge protection device mainly to protect the electronics in our rig. There is a strong potential in any campground for lighting based surges to occur was most of the wiring is underground and if lighting hits a tree it induces a current in any nearby wiring as it travels into the ground, which results in a surge of voltage. Wish A/S would install such protection as factory especially since the new units have quite a bit of electronic equipment on board.

David
__________________
david & bret
'02 Bambi LS
'99 34' Limited
Air Forums # 2159
Past President Heart of Texas Camping Unit
WBCCI # 7548
dtbw is offline   Reply With Quote
Old 09-01-2004, 12:59 PM   #5
3 Rivet Member
 
Join Date: Oct 2003
Posts: 132
Images: 2
Smile

David

Your analysis of the scenario we all face is correct; the grounding process is not as good as it could be both in terms of its capability ("the state of that connection varies as the trailer ages and is exposed to weathering") and its inherent design because of the traveling mode of our trailers. If we all parked our trailers (now, that would be painful), then the proper method of installing a metal ground spike, as you deftly point out, could and should be done.

Thank you for adding a measure of reality to the discussion.

Rick
Rick Alston is offline   Reply With Quote
Old 03-01-2010, 04:39 PM   #6
Rivet Master
 
ts8501's Avatar
 
2022 25' International
Savage , Minnesota
Join Date: Dec 2007
Posts: 753
Images: 7
Reviving this very helpful 5 1/2 year old thread on grounding the trailer; with a question. I am running new 12v wiring for my rear LED turn/stop signals. When I ground the 12v tester to my TV, and test the new trailer wiring, everything lights up when and as it should. When I then move to the back of the Airstream, and try to find a good ground and test the same wires while grounding to the Airstream, no lights. I touch different grounding points, even the frame, and still no lights, nothing. I might add the trailer is not hooked up to the TV, and the front tongue jack is not touching the floor. Not any other object on the trailer is touching the ground (floor) except the tires. I am thinking this has been my 12v issue all along; the trailer is just not grounded anywhere. Could it be this simple?
__________________
"I've got aluminum fever, and the only prescription, is more AIRSTREAM!!!"

'64 Safari Resoration Blog ("May"):
https://ts8501.blogspot.com/

TAC MN-6
WBCCI/VAC 11736
AIR 25979
ts8501 is offline   Reply With Quote
Old 03-01-2010, 05:33 PM   #7
1972 Travelux Princess 25
 
Cobourg , Ontario
Join Date: Oct 2008
Posts: 1,059
A 1 foot square steel plate buried 1 foot or more underground makes a good ground too. This is up to code, same as a rod driven into the ground.

Check your water pipe connection. If the pipe is metal, copper or galvanized, it will make an ideal ground. Just clamp a wire to it. I think most places these days use plastic pipe, too bad.
__________________
Living in the trailer park of sense, looking out the window at a tornado of stupidity.
Ganaraska is offline   Reply With Quote
Old 03-01-2010, 05:59 PM   #8
Rivet Master
 
ts8501's Avatar
 
2022 25' International
Savage , Minnesota
Join Date: Dec 2007
Posts: 753
Images: 7
Ganaraska:
All helpful, but let me add that I am currently indoors on a concrete floor. I am thinking I should attach the trailer to the TV, and drop one of the chains from the trailer to the floor. I must have enough 12v ground by then I would hope.
-Tim
__________________
"I've got aluminum fever, and the only prescription, is more AIRSTREAM!!!"

'64 Safari Resoration Blog ("May"):
https://ts8501.blogspot.com/

TAC MN-6
WBCCI/VAC 11736
AIR 25979
ts8501 is offline   Reply With Quote
Old 03-01-2010, 06:11 PM   #9
Rivet Master
 
vswingfield's Avatar
 
1983 34' Excella
1967 24' Tradewind
Little Rock , Arkansas
Join Date: Nov 2006
Posts: 3,825
Images: 32
Quote:
Originally Posted by ts8501 View Post
Reviving this very helpful 5 1/2 year old thread on grounding the trailer; with a question. I am running new 12v wiring for my rear LED turn/stop signals. When I ground the 12v tester to my TV, and test the new trailer wiring, everything lights up when and as it should. When I then move to the back of the Airstream, and try to find a good ground and test the same wires while grounding to the Airstream, no lights. I touch different grounding points, even the frame, and still no lights, nothing. I might add the trailer is not hooked up to the TV, and the front tongue jack is not touching the floor. Not any other object on the trailer is touching the ground (floor) except the tires. I am thinking this has been my 12v issue all along; the trailer is just not grounded anywhere. Could it be this simple?
This thread, and all the other posts relate to grounding the entire trailer to the (literal) ground. This has more to do with safety when dealing with alternating current and mitigating any dangers/damage from electrical surges.

The "ground" for 12 volt systems, what you are looking for, is a commonly used term that is something of a misnomer. What you are seeking is actually a path to the negative connection of your battery (& converter). When systems are referred to as 12 volt negative ground (earth for you British car fans) it means that a positive connection is established with a dedicated connection via wiring of some kind. Negative connections do not require a dedicated connection since the frame and shell have connections to the negative battery connection. This simplifies wiring because all devices share the same connection, behaving like grounding.

If you are getting nothing at the back of the trailer, are you connecting to clean metal for the "ground" connection? Remember, this is connection to the negative battery post, not the earth. That you are having success at the front of the trailer makes me suspect that this is not your problem. Are you sure that you are getting power (a 12 volt positive connection)?
__________________
Vaughan
vswingfield is offline   Reply With Quote
Old 03-01-2010, 07:03 PM   #10
Rivet Master
 
garry's Avatar
 
1969 31' Sovereign
Broken Arrow , Oklahoma
Join Date: Jan 2003
Posts: 1,455
Images: 7
OK are you are trying to test your Airstream turn/stop/running lights ??

They work from the TV through your 7 way plug so if you had the TV unplugged they would not work.

I think you would get better response if you start a new thread since this one is all about grounding for protection from lightning during storms.
__________________
Garry
garry is offline   Reply With Quote
Old 03-01-2010, 07:45 PM   #11
Rivet Master
 
TG Twinkie's Avatar
 
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 6,014
Images: 2
Blog Entries: 5
A lot of confusion here!

The 12 volt DC system is a 2 wire system, it has a positive and negative side. In most modern systems it is the Negative side that is commonly called "GROUND". This does not mean that the system is connected to EARTH ground. It is only a term used by the manufacturer of the trailers and tow vehicles to define one part of the circuit. It may be connected to EARTH ground through your trailer. But it is not a SAFETY circuit.

ON THE OTHER HAND! The ground wire in the AC (alternating current) side of the electrical system is a SAFETY device. It is part of a 3 wire system. One BLACK wire; 1 WHITE wire; 1 BARE wire. The Black wire is the "HOT" leg; The White wire is the NEUTRAL; and the Bare wire is EARTH GROUND.
If your trailer or the outlet it is plugged in to is not wired correctly, the frame and skin of the trailer could become HOT.

Most new AC electrical devices have at least 3 screws, 1 or 2 gold screws; 1 or 2 silver screws; and 1 green screw. The black wire(s) connects to the gold screws; the white wire(s) connects to the silver screws and the bare wire connects to the green screw. If they don't have screws they will have wires and the colors should be matched accordingly for these devices to be wired correctly.

In my opinion the neutral wire should not be connected to the trailer frame or skin in any way. This way if the outlet that you plug into is wired wrong, the trailer frame and skin will not be hot.

The ground wire should be connected to the trailer frame and skin to provide a safety mechanism. Should any AC wire that is hot, come in contact with the trailer frame or skin. If the trailer is properly connected to EARTH ground and there is an electrical fault that causes the trailer frame or skin to become hot, the AC current will take the path of least resistance via the ground wire and not through you, if you are touching the trailer.

The AC ground system is absolutely worthless if it is not connected properly to EARTH ground. The only safe method, is to use a ground plate buried in the ground, or a ground rod driven in the ground.

Do not fool yourself by thinking that the tongue jack is a proper grounding device! YOUR LIFE COULD DEPEND ON IT!
TG Twinkie is offline   Reply With Quote
Old 03-01-2010, 08:09 PM   #12
Rivet Master
 
vswingfield's Avatar
 
1983 34' Excella
1967 24' Tradewind
Little Rock , Arkansas
Join Date: Nov 2006
Posts: 3,825
Images: 32
Quote:
Originally Posted by TG Twinkie View Post
The 12 volt DC system is a 2 wire system, it has a positive and negative side. In most modern systems it is the Negative side that is commonly called "GROUND". This does not mean that the system is connected to EARTH ground. It is only a term used by the manufacturer of the trailers and tow vehicles to define one part of the circuit. It may be connected to EARTH ground through your trailer. But it is not a SAFETY circuit.
Agreed. That's why I put "ground" in quotes when referring to the 12 volt DC system
Quote:
Originally Posted by TG Twinkie View Post
ON THE OTHER HAND! The ground wire in the AC (alternating current) side of the electrical system is a SAFETY device. It is part of a 3 wire system. One BLACK wire; 1 WHITE wire; 1 BARE wire. The Black wire is the "HOT" leg; The White wire is the NEUTRAL; and the Bare wire is EARTH GROUND.
If your trailer or the outlet it is plugged in to is not wired correctly, the frame and skin of the trailer could become HOT.

Most new AC electrical devices have at least 3 screws, 1 or 2 gold screws; 1 or 2 silver screws; and 1 green screw. The black wire(s) connects to the gold screws; the white wire(s) connects to the silver screws and the bare wire connects to the green screw. If they don't have screws they will have wires and the colors should be matched accordingly for these devices to be wired correctly.

In my opinion the neutral wire should not be connected to the trailer frame or skin in any way. This way if the outlet that you plug into is wired wrong, the trailer frame and skin will not be hot.

The ground wire should be connected to the trailer frame and skin to provide a safety mechanism. Should any AC wire that is hot, come in contact with the trailer frame or skin. If the trailer is properly connected to EARTH ground and there is an electrical fault that causes the trailer frame or skin to become hot, the AC current will take the path of least resistance via the ground wire and not through you, if you are touching the trailer.

The AC ground system is absolutely worthless if it is not connected properly to EARTH ground. The only safe method, is to use a ground plate buried in the ground, or a ground rod driven in the ground.

Do not fool yourself by thinking that the tongue jack is a proper grounding device! YOUR LIFE COULD DEPEND ON IT!
Again, agreed. Proper safety with the AC electrical system is imperative!

The AC and DC systems are different.

Garry's suggestion about starting a new thread is a good idea, too.
__________________
Vaughan
vswingfield is offline   Reply With Quote
Old 03-02-2010, 07:50 AM   #13
Rivet Master
 
TG Twinkie's Avatar
 
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 6,014
Images: 2
Blog Entries: 5
to ts8501

Let me get this straight.
You have no tail or marker lights that work unless you connect one wire of your tester to the frame of the tow vehicle and the other to a light or wire on the trailer?
When you say "everything lights up as it should". Do all of the lights come on?
Do you have your trailer plugged into your TV?
Your trailer is not hooked to the hitch on your TV.
Sounds to me like you ar missing the negative side of your circuit.
You ran new wires for the tail lights and new wires for the marker lights and new wires for the turn signals?
Do you have a 7 pin plug for your trailer wiring? If so, there should be 1 wire in that connector on the TV side that is connected to the frame of your TV. There should also be one wire one the trailer side connected to the frame of the trailer. When the connectors are plugged together, this is what complets the negative side of the circuit.
Try this. Connect a wire (a jumper) directly from the frame of the TV to the frame of the trailer. This is only a test to determine if you have a completed negative half of the circuit. If you have a set of jumper cables for jump starting a car, you can use it for the "jumper". The handles on the jumper should be red and black. Use the "Black" ones. Make sure the area that you connect to on the TV and trailer are scraped clean, removing any paint or rust.
You will need to have your connector for the TV and trailer plugged together. And the light switch turned on in your TV. The ignition must be on to test the turn signals.
If this works, what it is telling me is that the negative side of the circuit is not completed through your connector. Some people use the hitch to connect the negative side of the TV and trailer. This is not a good practice and can cause all of the lights on you trailer to blink when you are on rough roads.
The negative side of the circuit on both the TV and trailer should be connected through the 7 pin connector.
Let me know what happens.
TG Twinkie is offline   Reply With Quote
Old 03-03-2010, 05:59 AM   #14
Rivet Master
 
ts8501's Avatar
 
2022 25' International
Savage , Minnesota
Join Date: Dec 2007
Posts: 753
Images: 7
TG Twinkie:

You have the current set-up correct. When I am back at the trailer on Saturday, I am going to test this out.

-Tim
__________________
"I've got aluminum fever, and the only prescription, is more AIRSTREAM!!!"

'64 Safari Resoration Blog ("May"):
https://ts8501.blogspot.com/

TAC MN-6
WBCCI/VAC 11736
AIR 25979
ts8501 is offline   Reply With Quote
Old 03-03-2010, 05:54 PM   #15
Rivet Master
 
TG Twinkie's Avatar
 
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 6,014
Images: 2
Blog Entries: 5
Trailer wiring

Tim,
Keep me posted, I'll be glad to help in any way I can.
Doug
TG Twinkie is offline   Reply With Quote
Old 03-04-2010, 02:28 PM   #16
1972 Travelux Princess 25
 
Cobourg , Ontario
Join Date: Oct 2008
Posts: 1,059
Quote:
Originally Posted by ts8501 View Post
Ganaraska:
All helpful, but let me add that I am currently indoors on a concrete floor. I am thinking I should attach the trailer to the TV, and drop one of the chains from the trailer to the floor. I must have enough 12v ground by then I would hope.
-Tim
The kind of ground you need has nothing to do with the floor or dirt.

Look at it this way. Every electrical circuit needs a way to get power TO the load (light) and power BACK to the power source (battery).

This means every circuit needs 2 wires, one to the load, one going back.

Somebody cleverly figured out, that all you really need is a piece of metal in place of the wire going back to the battery. And guess what, your car is made of metal! Also your trailer is made of metal!

By using the car or trailer in place of a piece of wire, they make your wiring much simpler and save a fortune in wire.

When they do this it is called "grounding" the wire, even though no actual ground or dirt is involved.

I hope this is clear.

In your case, if the trailer lights are grounded to the trailer, and the power comes from the car, you have to have the trailer and car connected together to complete the circuit.

When you plug in your trailer lights this should happen automatically because one of the wires in the harness is a "ground" wire that connects your trailer to your car.

If this is not happening you need to check the ground circuit in the plug. For a temporary test you can connect a jumper cable from your car frame to the trailer frame. Be sure the connection is on bare metal. Any rust, dirt or paint can act as an insulation.

Just hitching up will usually create a ground. But this is not always certain especially if you grease the ball. So they add a ground wire to be sure.
__________________
Living in the trailer park of sense, looking out the window at a tornado of stupidity.
Ganaraska is offline   Reply With Quote
Old 03-07-2010, 09:21 AM   #17
Rivet Master
 
ts8501's Avatar
 
2022 25' International
Savage , Minnesota
Join Date: Dec 2007
Posts: 753
Images: 7
Success!

Although I forgot to take a picture with the rear lights on, you can see the difference in these two shots. The outside shot was taken in late November, clearly showing my temp light set-up, old Plexi-glass window, and non-refurbished Airstream Name Plate. A proper ground was the final answer. After testing the left side lights with the new wiring that I had run, it became temporary wiring, as I was also able to hook up everything using the existing trailer wiring. The new umbilical cord, and with grounding of the truck and trailer, and my rear lights works great! Now I can finish installing the new tear drop running lights (notice the three aluminum tape band-aids above the Airstream Nameplate. I am very happy to have this task behind me, as it has been the one item that has been a thorn in my side since last fall.
Attached Thumbnails
Click image for larger version

Name:	DSCF6022 mod.jpg
Views:	171
Size:	283.1 KB
ID:	97595   Click image for larger version

Name:	DSCF6279 mod.jpg
Views:	147
Size:	325.5 KB
ID:	97596  

__________________
"I've got aluminum fever, and the only prescription, is more AIRSTREAM!!!"

'64 Safari Resoration Blog ("May"):
https://ts8501.blogspot.com/

TAC MN-6
WBCCI/VAC 11736
AIR 25979
ts8501 is offline   Reply With Quote
Old 03-08-2010, 07:21 AM   #18
Rivet Master
 
TG Twinkie's Avatar
 
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 6,014
Images: 2
Blog Entries: 5
Glad we could help. I get a lot of good advice from this forum. It is a great resource. If you are able to do the work yourself, it saves $$$. And the other thing is, you can find the guy who did the work.
TG Twinkie is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
hitch wiring question Craig Lights - Interior & Exterior 4 07-18-2004 06:09 AM
Is House Wiring the same as Automotive Wiring? swebster Mechanics Corner - Engines, Transmission & More... 7 06-15-2004 06:11 AM
trailer wiring Cruiser Electrical - Systems, Generators, Batteries & Solar 4 09-02-2003 01:43 PM
Electr. Tongue Jack Wiring?? roessler Jacks, Stabilizers, Lifting and Leveling 12 07-17-2002 11:00 AM
TV Antenna wiring??? tenrsingr Audio, Video & TV 6 05-06-2002 02:16 PM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 10:53 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.