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OK, it HOT here and raining too much to ride and its July.
So I will tackle this issues.
I have had BOTH the problems.
HOT CHASSIS.
Most all wiring done in the LQ trailers will attach the GREEN ground 
wire of the 3 wire power cable to the CHASSIS, this is correct it is 
suppose to be the dead earth ground.

Next they ALSO connect the NEUTRAL WHITE wire to the chassis. This is 
the cold or negative or return side of the power circuit.
The other wire is the BLACK HOT line to the breakers.

The trailer is NOT actually at ground potential since it is on RUBBER 
tires and NOT on the ground-earth. It 'floats' above ground.

Depending on the outlet you plug the trailer to, the actual ground 
circuit may be quit long. Most outlets boxes do not have the GREEN 
ground wire connected to an earth ground post at the outlet box.

The distance of the power cable run (length) back to the power panel is 
quite LONG at most camp grounds and most  home trailer outlet 
connections..  It is where the WHITE and GREEN wires are also connected 
to the same buss and then to an actual earth ground post at the main 
power panel.

The  problem occurs when there is a slight voltage potential -called 
Eddy Currents, between the trailer shell- metal and the actual earth.

The longer the run the higher this voltage condition. This is due to the 
actual earth is true ground while the green and white wire tied together 
are NOT really true ground. The long run will cause inductive currents 
in the so called return lines (white and green) Its a long run from the 
trailer to the site power panel back to the earth ground rod.

Thus there is voltage potential difference between the trailer skin and 
dirt-ground. It can be as high 50 to 60 vols AC.. ZAP.
You offer a better shorter connection to ground when you touch it and 
drain off this induced voltage.

One way to prove this condition is to plug into a GFI outlet GROUND 
FAULT. My trailer and others will pop the GFI breaker. Ground Fault 
Indicator. Yep there is one - the floating ground and white wire are 
connected in the trailer.


That may not be all clear. Not too many EE terms - which I am NOT one by 
degree.. :)

The fix.
DISCONNECT FROM THE POWER OUTLET or you will be ZAPPED a good one.

Open the breaker box in the trailer.
Disconnect the WHITE neutral return wire from the power panel buss plate 
in the trailer.
 Then remove all the WHITE wires from the ground plate buss. There is 
one white wire for each breaker.
When all the WHITE wires are disconnected. Go around and UNPLUG anything 
that is plugged in to an outlet. Including the power converter box.

Take an OHM meter and connect one lead to the chassis-green wire and 
touch to each of the WHITE wires one at a time -- THERE SHOULD BE NO 
CONTINUITY from a white wire to the chassis.

Now we know there is no way for  WHITE wire    connection to the 
chassis. NO eddy current leakage.

There are some power boxes that have insulated WHITE buss plates - that 
is they ,are not attached to the metal frame but have a plastic 
insulator under then. If your trailer has this - I bet you dont get 
shocked, as long as the GREEN wire is not connected to the white

Or you can make one by removing the one that is in the power box and 
mount it with plastic shims and screws. Then all the WHITE leads are 
connected back to the buss and none connected to the frame.

OR you can use wire nuts and just connect all the WHITE wires together. 
I did that to mine as I only had 3 wire - two breakers with the incoming 
power cable. Some LQ have 3 or 4 breakers. Whatever method you use, you 
have to connect ALL the white wires together and to the WHITE wire in 
the main power cable- with no connection to the chassis.

Now test again - no connection between the white wires and the chassis. 
The return line is now floating. The GREEN wire is still going to the 
chassis. This also includes all the green wires from the circuits in the box
Since the GREEN wire is NOT part of the actual electric circuit there is 
no current on that wire- the chassis eventually will be connected back 
to the green earth ground at the main power panel. A long run but its 
the real ground.

OPTION 2
If you dont want to do all that, then take a battery jumper cable and 
connect to the trailer metal and drive a ground rod in the ground about 
a foot or so and connect to that. The leakage in the system will be 
shunted to actual ground and you wont get zapped.
However if the power source uses GFI they will pop for sure.

I have done the above ground the chassis for years. The horses tied to 
the trailer will get zapped if they touch it. Not good.

When you use a generator this does not occur since ALL the power lines - 
white green and black are inside the trailer and there is no connection 
to the earth. Most generators will float the white wire and not connect 
it to the green ground wire.

I am sure a 'real' EE can describe this better.

The problem can be resolved.
1 Re-wire the breaker box to float the WHITE neutral wires
2 Physically ground the chassis to a metal post in the ground.

--
Roger R


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