Connecting home receptacles to a ground rod.

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powerplay

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A tester indicated that receptacles were properly wired with a "ground"...outside there was a ground rod with #14 stranded wire running to the receptacle box. In another part of the home there was another ground rod with a stranded #14 wire going to the receptacle box. I checked the resistance from white common to the prong connected to the ground rod and read 63 ohms. This install provides a path to ground, but with some resistance which would probably not divert power away from a person being shocked, nor trip the breaker? Connecting it to copper plumbing which would be connected to the System Ground Plate would ensure less resistance and more chance of tripping a breaker? Is installing a three prong receptacle connected to a ground rod separate from the incoming service someone's creative way to provide a path to ground unacceptable, and if it is ok would it require connecting all ground rods together??
 
powerplay said:
A tester indicated that receptacles were properly wired with a "ground"...outside there was a ground rod with #14 stranded wire running to the receptacle box. In another part of the home there was another ground rod with a stranded #14 wire going to the receptacle box. I checked the resistance from white common to the prong connected to the ground rod and read 63 ohms. This install provides a path to ground, but with some resistance which would probably not divert power away from a person being shocked, nor trip the breaker?
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Correct
Connecting it to copper plumbing which would be connected to the System Ground Plate would ensure less resistance and more chance of tripping a breaker?
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Correct. Current code requires the connection to be made within the first five feet of where the water pipe enters the building

Is installing a three prong receptacle connected to a ground rod separate from the incoming service someone's creative way to provide a path to ground unacceptable,...
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Yes
and if it is ok would it require connecting all ground rods together??
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In this context there is no reason to keep them.
 
A ground rod or any other grounding electrode plays no role in the tripping of an overcurrent device nor does it divert current away from a person.

What makes the breaker trip or the fuse blow is the bonding of the equipment grounding conductor to the neutral at the service but even this in no way diverts current away from a person.
 
I think you could make this code compliant by tying all the ground rods together with a #6 copper wire and running that wire back to the main service neutral/ground bar. Not sure if that is easier than grounding the receptacle via a pathway inside the house to a point on the ground electrode system or the Service disconnect panel.

Those little testers use neon or LED lights. Doesn't take much current to light them up, so they'll show a poor path as being connected when it really won't be during significant current flows.
 
EGs via ground rods are not and can not be made compliant with the code when installed in this manner. The equipment ground must be routed with the circuit conductors, not circling around the house from rod to rod no matter where it ends up or how big the wire. Not saying it won't work, just not compliant.
 
The approach in 250.130(C) would not be possible if you had to run the grounding wire with its associated conductors. See Exception 1 to 300.20(A)(1).
 
ptonsparky said:
Sure enough. I never would have dreamt of driving a ground rod for each reccepts EG. Then connecting those to a hose bib to make it legal.
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Since you have to connect to the existing GES, what would be the purpose of driving a ground rod?
Why wouldn't you just run the wire to wherever you were connecting to the GES instead of to a rod, then to the GES?
 
ptonsparky said:
The suggested fix for using ground rods alone as an EG (existing) was to connect them all to the GES.
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I understand that but my question is if you have to tie all the rods to the GES why go to the trouble of driving rods? Why not just run from the receptacle to the GES? Same thing, just not having to drive the rods.
 
Little Bill said:
I understand that but my question is if you have to tie all the rods to the GES why go to the trouble of driving rods? Why not just run from the receptacle to the GES? Same thing, just not having to drive the rods.
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Just what they should have done in the first place.

Little Bill said:
Thanks for the link. I have no trouble understanding the concept of grounding vs bonding.
My response was trying to figure the logic in driving the extra ground rods when all would be needed was to tie directly to the GES some place.
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The logic was flawed?
 
Little Bill said:
Thanks for the link. I have no trouble understanding the concept of grounding vs bonding.
My response was trying to figure the logic in driving the extra ground rods when all would be needed was to tie directly to the GES some place.
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Boolean logic? ... there are a million different ways to do things, they just don't always work well.... :p
 
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