Can I make a new ground pipe at an outdoor appliance instead of running a separate ground wire?

Question

I have two legs of my 240 V appliance and the neutral wire, but no ground wire available, but plenty of room for burying a ground pipe and strap. Can I just drive another ground pipe at the location of the appliance and use it like that? If the answer is yes, should I also reconnect the new ground wire to the neutral wire at the appliance, or will this cause ground loops?

Answer 1

No. Ground rods and ground wires are not equivalent

and actually have different jobs.

The ground wire's job is to return dangerous fault current. So if a hot wire shorts to the chassis of equipment, the ground wire carries it back in large quantity, enough to get a fast breaker trip (so 5-10x normal current).

Dirt doesn't conduct electricity nearly well enough for that. LOL no not slightly! That would leave the equipment energized, shocking people and/or starting a fire.

No, the ground rods are only useful as a grounding electrode - first, you know how neutral is considered "safer" because it is near 0 volts when everything is working properly? That's one job of the grounding electrode. The other is to return natural electricity to its source, such as ESD or (optimistically) lightning.

You really need to use proper wires, though

I have never heard of a situation where modern wiring failed to provide the necessary ground wire. This suggests to me that you are adapting an extremely ancient installation that is "grandfathered" and not allowed to be upgraded... or cobbling together a circuit using random or found wires... or misusing the provided ground wire as a neutral wire.

Which sounds like a cost cutting measure, perhaps by the sky-high cost of copper right now.

Don't do that! Don't waste your time and take big chances with safety! What you should be doing is getting over any irrational fear of large aluminum wire. That stuff is so cheap you don't mind installing it new. And there has never been anything wrong with it, when the terminals are rated for aluminum (all panels are) and the torques are set halfway correctly.

Outdoor installations especially have a tendency to kill people, in ever more imaginative ways. Like this shortcutting blankity-blank who decided to burn down a whole county. Don't be "that guy".

Do it right or don't do it. You're on the right track by asking advice.

Answer 2

To narrowly answer your vague question, no you can't just drive a new separate grounding electrode.

NEC 250.50 says all electrodes are to be bonded together. I guess technically you could drive another properly sized pipe electrode and use an approved connection to an existing electrode and then connect to your new ground wire to the new extension of the Grounding Electrode System, but I don't really think that's what you were asking.

You have other options about how you can connect an Equipment Grounding Conductor to the Grounding Electrode System but we need a little more help with existing circuit conductor/cable/raceway type, amperage of appliance circuit.