Grounding Question

Generally, you want to "bond" the Neutral to Green Wire/Safety ground in one location... For North American homes, that is typically inside the main breaker/fuse panel (you will see both a green wire ground bus, and a white wire neutral bus--And somehow, they will be attached together inside the panel).

Note, this is not really true outside the home.. For example, you have a pole mount 120/240 VAC Split Phase transformer on the pole. The neutral is grounded (typically) at the base of the pole. Also, this transformer serves ~5 homes on your block, and each home has a ground to neutral bond too). In the grand scheme of things, this is very good for lightning control (lightning takes the shortest path to ground--It does not like to follow electrical wiring more than a few 10's of feet). And the resistance from ground to earth only carries, perhaps, 5-10 amps or so worst case (120 VAC / 25 Ohm worst case grounding=4.8 amps)--So, the "AC ground current" does not really do much when you have 5 volts drop from pole to house (5 volts / 25 Ohms=0.2 amps).

Inside your home, when you have "single point" ground to neutral bonding, there is no connection for parallel current flow on both Neutral and Ground wire.

However, if you tied white to green both in the main panel, and (for example) at an outlet. Then the current flow will be divided between white and green because of this. And we do not want this (don't want current flow through green wire unless it is, for example, a short circuit from Hot to Ground--To trip the breaker). There are further details why multi-point grounding of a home's neutral system with the safety ground is not good/safe... We can discuss more if you are interested.

Grounding is one of the most complex questions we talk about here... There is a good reason why the best idea is to follow code--This helps reduce "inadvertent" problems (things people and equipment don't "expect").

Things do get complicated when you talk about gensets and RV installations with multiple power sources (utility, genset, AC Inverter).

For example, in my (limited) experience, more or less, smaller (3,000 Watts or less?) gensets and AC inverters do not ground bond neutral and ground. And most will ground bond in the genset/inverter if over ~3,000 Watt output. So, this gets complicated when you are powering your home with utility power, a backup genset, AC inverter... The typical answer for your home, is to make sure that the white/green wire bond is "lifted" in the (larger) gensets and AC inverters.

For RVs, because of the complexity (for example, at the RV park, their neutral/green wire ground is somewhere back on their AC panels). Using a transfer switch with an extra lead to ground bond when the genset or AC inverter are supplying power, and "not bond" when utilty power is supplied.

And even more complexity, (generally) you should only ground bond a PSW/TSW (pure/true sine wave) AC inverter (Hot and Neutral are "floating"/isolated by a transformer). For MSW (modified square/sine wave) do not neutral/ground bond the output of AC inverters because the AC output is not isolated (connects back to the battery +/- bus, no transformer isolation).

That is some of the details behind why the answer depends on your system's details. Short answer is neutral+ground bonding does not create a parallel current path with single point bonding.

-Bill

If I follow you correctly, sounds find.

You can have multiple ground rods... Either (or both) for better lightning grounding or if you have sandy/dry/rocky soil that has poor conductivity. I suggest that running a 6 AWG between ground rods improves "safety grounding" for AC voltages and better lightning control.

"Earth Grounding" for your AC power does not really make things electrically safer (120/240 VAC). Tying Neutral to grounding and 'big metal" (water pipes, gas pipes, electrical panels, etc.) is what makes things safer. This provided a return path (from "grounded metal" back to the ground+neutral bond) so that a circuit breaker can be tripped.

Earth Grounds are generally for lightning protection (get lightning energy away from house). A short circuit from 120 VAC "Hot" only will drive ~5-10 amps into the earth--Not enough to trip a breaker.

Other grounding issues that "need earth grounding" such as making some fluorescent tube fixtures start easier, spark ignition on stoves for flame detect, and cathodic pipe/ironwork protection ("charge" the pipes so they do not rust, phone systems so they do not have their wires corrode when they get wet)...

-Bill

In the USA... In general (I am not a code expert) there is a galvanic isolation (fancy name for "insulated pipe joint" joint out at/near the gas meter (line in ground is part of utility's cathodic protection system. In the house, the gas lines were "floating").

Today, our local code requires that the gas line and hot water line be tied (grounded) to the cold water pipe and ground rod (add ground rod if not present in old / original structure).

-Bill