I'd like to install an RV outlet (120v, 30amp) in our parking area. Unfortunately, I only have two wires available to that location and adding a third wire would be quite difficult. Can I use the two available wires for hot and neutral and drive in a grounding rod next to the outlet for the ground? The two wires I have available are 6 gauge, already black and white and terminate next to the breaker panel, so can easily be connected to a new breaker. I just don't have a third wire for the needed ground. Thanks!

ABSOLUTELY NOT.
A ground rod does NOT provide or "create" a ground as we know it for circuit protection and shock safety.
A fault to a lone ground rod will only serve to electrify the ground around it and bring up worms.

I agree with Stan [like always :D].


Mtn,

It would be best (and required) to install a new cable with grounding conductor.

Thanks for the fast replies! A quick follow-on question:

It was my understanding that if you have a separate building with no metallic connection between it and the main building and you want to set up a sub-panel in the outbuilding, but only have hot and neutral wires running to it, then you can use the neutral wire as a "grounding (neutral) conductor". If I understand correctly, the grounding rod at the outbuilding would be connected to the ground bar in the sub-panel, the neutral wire connected to the neutral bar, and then the two bars are bonded together. I know that the ideal would be running a separate ground wire to the outbuilding (and maybe that's now required by code for new construction?), but I got the impression that this was allowed.

Assuming that's possible for an out-building, could one treat the RV outlet box like a separate building and bond the neutral to a grounding rod and use that as ground for the RV outlet?

While what you say is true (although removed from the 2008 NEC), it would not apply to your RV recepetacle.

You are running a branch circuit. This is NOT a feeder, not is it a "separate structure" as it applies to this section of the code.

Still, in the case you describe, the safety ground does NOT come from the ground rod. It comes from the neutral to ground bond in the panel.

Need a second opinion on this; Would a GFCI breaker be allowed provided the standard "No Ground, GFCI protected" warning is placed on the outlet and possibly the entrance to the trailer?

No. That allowance is just for replacements.

Maybe adding a wire wouldn't be as difficult as you think. Tell us where and how these wires are run and maybe there is an easy way to do it you haven't thought of.