I'm going to try to address two of your posts more clearly, now that the information has had time to percolate to the residual neurons and I've slept on it at least once.
The fridge controls run on 12 volt. If you take the 12 volts away you will have no fridge.
Above, looks like you flipped the idea of removing the 12vdc with the 110vac.
TLDR my response: The solution with the OEM Stock Norcold fridge, (the easy way) was to remove the screwed-on earth (green) wire from the fridge chassis, OR (the harder way) leave the earth wire connected, and re-wire the entire fridge so that it wasn't using it's frame as a +12vDC return path to -12vDC. IN EITHER CASE, adding a GFCI/RCB to the main circuit breaker/fuse box in the cabin.
end tldr
Removing the earth wire and taping it up, tagging it off, does not remove the 12v, 110vac or LP gas operation. It DOES remove a 1980's and earlier safety design. Whereby, if there was a leakage from the hot 110vac (black) wire to the fridge chassis, a person would NOT get shocked because, ideally, that leakage would go to ground (it would touch the case), and (hopefully when doing so) pull more than 10 amps (whatever the circuit breaker is rated at) and cause the circuit breaker to trip, killing power to the fridge.
In a washing machine example: visualize some interaction between the hot wire in a washing machine, maybe it comes loose, and either the water flowing through it or the metal body it touches. Without an earth ground, someone could touch the washing machine and a nearby dryer (which we presume is properly grounded) or sink (which with older copper pipes is very likely grounded), and the current would pass from one hand to the other, electrocuting them. This is why earth ground was added.
Enter the RCB/GFCI: it uses a magnetic interlock, that is triggered where there is an imbalance in the flow out of power from the hot to the neutral return. It triggers faster than a circuit breaker. A GFCI can get triggered spontaneously when a piece of equipment is faulty, without a loud 'crack' or 'zap', which can make those conditions slightly more hard to determine the cause - particularly if it's protecting an entire electrical box - as they trigger so fast and at such low current, there isn't the traditional smell of smoke to follow.
However, because RV's have simpler and less lines running from their main circuit breaker box, if one GFCI wired into the panel (looks similar to a circuit breaker and should fit into an existing cabin electrical box), protects all of one phase (in the case of a 30 amp hookup) or two phases (in the case of 50amp hook-ups), then it should not be that difficult to track down the problem piece of equipment.
In an older house or RV setup, when GFCI's first came out, GFCI's were installed only in outlets, protected that outlet, and any subsequent outlets that were downstream from that outlet should have been wired into the LOAD side of that GFCI, chaining it off the GFCI function. So if you have GFCI's in your RV outlets, you will also have outlets that do not have a GFCI/test/reset button. If a neighboring GFCI is reset or tripped, that non-GFCI outlet on the same circuit, should go dead, also.
I believe the trend or standard now is to install a single RCB/GFCI in the main electrical box, which trips whenever AC Hot leaving the box leaks. This also protects the AC wiring in the RV, ahead of the outlets and appliances, as it can take much less leakage to cause a fire than what it takes to trip a circuit breaker.
..he got shocked one time getting in his RV. He started checking and found he was getting AC voltage between the RV and a ground rod driven into the ground. His solution at the time until he could find the leak was to drive the rod and run a ground wire from the RV to the ground rod.
... military 'standards' ...
So isolating the AC completely from the RV frame will in effect protect the occupants from electrocution in the event of an electrical leak or short to ground?
What you are describing indicates he had a leak from his 110vac hot to the chassis. Not enough to blow a 110v AC fuse or trip a 110v AC circuit breaker in his cabin's main electrical box. If he had an RCB/GFCI in the main electrical box, it would have tripped before he felt the buzz.*
* With the caveat, if the hot-to-ground fault condition was AFTER his main cabin electrical box. If it wasn't, for instance, if there was damage to his main shoreline power cord, and it was shorting hot to the RV chassis, at some point where the cord was cracked or rubbing, the GFCI afterwards would not have picked it up. However, the SHORE supply should be GFCI protected imo, and that's an upgrade several people may not have.
For instance, humidity can cause a low-level conductance, which the GFCI will pick-up and trip over. But, with only fuses/circuit breakers, enough current could flow through to cause a buzz.
On: military standards
I would personally only do that if the generator didn't have a GFCI. If I'm mounting my own unit, and the genset does not have it's own GFCI, I'm going to make sure that the power cord coming from the generator to the main cabin electrical distribution box in the RV, is double-insulated, or inside of conduit/metal housing that is earth grounded with the earth lead from the generator, and also not connected to the RV chassis.
To reiterate: The incoming shore/genset conduit IS earth grounded, however there's no metal-metal contact between the conduit and the chassis.
The military standards part probably emanates from pre-GFCI protection. There's no reason (I can think of) why you can't have a ground rod in addition to a GFCI. However, if you've noticed, it's required I think, at job-sites to have a GFCI ahead of tools. And several modern tools do not have a ground prong, if they aren't battery-operated already. However, those battery-operated chargers, also don't have a ground prong (although the cases are usually nylon/plastic). The prong is left off, not because someone broke it off, but because in the past, they were broken off, and better insulation along with GFCI, means the leak-to-case (ground) conditions that the ground wire was supposed to protect against, are surpassed by the GFCI.
A typical condition: a tool getting wet.
So isolating the AC completely from the RV frame will in effect protect the occupants from electrocution in the event of an electrical leak or short to ground?
TLDR Yes.
end tldr
Only if the hot line on that AC is GFCI protected.
If somehow the chassis becomes live because a fault condition, or an appliance does, even to a much less extent than a full connection, the GFCI will sense that there is power flowing out of the hot, that is NOT being returned on the neutral (it's going somewhere else), and trip/disconnect the circuit.
And lastly, searching 'OSHA GFCI' brings up:
https://www.osha.gov/SLTC/etools/construction/electrical_incidents/gfci.htmlWhich reminds me that a GFCI does not protect if some asshat grabs both a hot and a neutral wire. Because in that circumstance, the entire output of the hot is flowing through the neutral.
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