Two ground rods

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Hv&Lv

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Looking for some other opinions here. Example: I have an older house with a pipe electrode driven under the fuse panel in the center of the house, with the EGC connected from the panel straight to the pipe. Because the new smart meters aren't particularly fond of lightning induced surges, I want to drive an additional rod at the meter socket and connect the EGC from the new rod directly up to the meter base. The two will not be connected together except through the grounded conductor (neutral).

Another example: I am not sure an older house has a grounding electrode installed at all. I drive a rod at the meter base and install a GEC from the rod and the meter base. What I don't realize is that the water pipe is used as the electrode and is connected at the fuse panel in the house. Again, the two only share a common neutral connection.

What, if any, problems do you see with this installations.
 
Hv&Lv said:
Looking for some other opinions here. Example: I have an older house with a pipe electrode driven under the fuse panel in the center of the house, with the EGC connected from the panel straight to the pipe. Because the new smart meters aren't particularly fond of lightning induced surges, I want to drive an additional rod at the meter socket and connect the EGC from the new rod directly up to the meter base. The two will not be connected together except through the grounded conductor (neutral).

Another example: I am not sure an older house has a grounding electrode installed at all. I drive a rod at the meter base and install a GEC from the rod and the meter base. What I don't realize is that the water pipe is used as the electrode and is connected at the fuse panel in the house. Again, the two only share a common neutral connection.

What, if any, problems do you see with this installations.
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Off the top of my head, I don't think it would be NEC compliant without bonding all the electrodes together. But I think since you are a POCO guy (I think), so it seems to me that NEC would not apply if you are only connecting the GE the the meter socket, I.E. this would be no different than any other GE the POCO installs anywhere along thier system.
 
Hv&Lv said:
....

What, if any, problems do you see with this installations.
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texie said:
Off the top of my head, I don't think it would be NEC compliant without bonding all the electrodes together.
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Actually, it is NEC compliant, provided the fuse panel referred to contains the service disconnecting means. GEC's can be connected anywhere along the service entrance [grounded] conductor.


texie said:
But I think since you are a POCO guy (I think), so it seems to me that NEC would not apply if you are only connecting the GE the the meter socket, I.E. this would be no different than any other GE the POCO installs anywhere along thier system.
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That would depend on the location of the service point. While the POCO can have requirements beyond the service point, those requirements usually don't conflict with the NEC.
 
texie said:
Off the top of my head, I don't think it would be NEC compliant without bonding all the electrodes together. But I think since you are a POCO guy (I think), so it seems to me that NEC would not apply if you are only connecting the GE the the meter socket, I.E. this would be no different than any other GE the POCO installs anywhere along thier system.
Click to expand...

I was curious about the "bonding all the electrodes together" part. This is what I was thinking. This install would be on the NEC side of the meter socket, even though we would be adding it. It would be for protection of our meter.
 
Smart $ said:
Actually, it is NEC compliant, provided the fuse panel referred to contains the service disconnecting means. GEC's can be connected anywhere along the service entrance [grounded] conductor.
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Multiple grounding electrodes? You know some of these old houses don't really have a whole house disconnect.
My mind keeps telling me parallel rods, and voltage potential between different areas of the house when the rods are 25 feet apart or better and not bonded with an unbroken EGC.

I keep picturing a power company distribution system and circulating ladder currents...
 
Hv&Lv said:
I was curious about the "bonding all the electrodes together" part. This is what I was thinking. This install would be on the NEC side of the meter socket, even though we would be adding it. It would be for protection of our meter.
Click to expand...

After further thought, maybe this would comply with 250.54 if you called it an auxillary GE and only connected it to the can of the meter (not directly to the bonded neutral in the can). It would seem that this would accomplish your goal and be NEC compliane as well.
 
Hv&Lv said:
Multiple grounding electrodes?
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Yes.

You know some of these old houses don't really have a whole house disconnect.
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Perhaps not one single disconnect... but even current code permits six ;)

My mind keeps telling me parallel rods, and voltage potential between different areas of the house when the rods are 25 feet apart or better and not bonded with an unbroken EGC.
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Bonding together with a GEC is no different electrically than bonding together with the grounded service conductor. The unbroken or irreversibly-connected GEC is just a precaution measure to prevent unbonding. Using the grounded service conductor might even shorten the travel time for some electrons. :lol:

I keep picturing a power company distribution system and circulating ladder currents...
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Picture grounding grid and step potential mitigation techniques ;)
 
As a POCO don't you already have about a million grounding electrodes connected to the shared HV and LV neutral? One more shouldn't hurt. As long as all the grounding electrodes are bonded in the premises wiring NEC is happy.
 
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texie said:
After further thought, maybe this would comply with 250.54 if you called it an auxillary GE and only connected it to the can of the meter (not directly to the bonded neutral in the can). It would seem that this would accomplish your goal and be NEC compliane as well.
Click to expand...

It is an aux grounding electrode, and you can install as many as you want and connect to either grounded conductor at service equipment or to equipment grounding conductor beyond service equipment.
 
Hv&Lv said:
...

Another example: I am not sure an older house has a grounding electrode installed at all. I drive a rod at the meter base and install a GEC from the rod and the meter base. What I don't realize is that the water pipe is used as the electrode and is connected at the fuse panel in the house. Again, the two only share a common neutral connection.

...
Click to expand...

texie said:
After further thought, maybe this would comply with 250.54 if you called it an auxillary GE and only connected it to the can of the meter (not directly to the bonded neutral in the can). It would seem that this would accomplish your goal and be NEC compliane as well.
Click to expand...
See * below.

kwired said:
It is an aux grounding electrode, and you can install as many as you want and connect to either grounded conductor at service equipment or to equipment grounding conductor beyond service equipment.
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If the water pipe is used as an electrode and has no supplemental electrode as required by 250.53(D)(2), installing a ground rod electrode becomes the required supplemental electrode... and 250.53(D)(2) specifies where it can be bonded:
(1) Grounding electrode conductor(2) Grounded service-entrance conductor *
(3) Nonflexible grounded service raceway
(4) Any grounded service enclosure
(5) As provided by 250.32(B)
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Smart $ said:
See * below.


If the water pipe is used as an electrode and has no supplemental electrode as required by 250.53(D)(2), installing a ground rod electrode becomes the required supplemental electrode... and 250.53(D)(2) specifies where it can be bonded:
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Kind of not the OP's concern, his intention is to have an electrode connected directly to the meter enclosure, which is allowed, if anything it is an aux electrode. As POCO representative his main interest is not whether or not the load side of meter is done properly - that is for inspection department and owner/contractor to take care of.
 
kwired said:
Kind of not the OP's concern, his intention is to have an electrode connected directly to the meter enclosure, which is allowed, if anything it is an aux electrode. As POCO representative his main interest is not whether or not the load side of meter is done properly - that is for inspection department and owner/contractor to take care of.
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...and I agree... but my post was not aimed directly at his concern. It was aimed twofold. First regarding texie's contention that the new GEC should not be connected to the grounded service conductor, and second regarding your statement, in part, that the new GEC could be connected to an EGC. On that part, if the water pipe is used as an electrode, with no supplemental electrode, adding an electrode and bonding to an EGC would be a violation. As long Hv&Lv stays on the service side of the disconnecting means, he's good to go.
 
kwired said:
Customer wouldn't mind:happyyes: Maybe you can get rid of my meter also:)
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Why don't you like it?
We have some customers that absolutely do not want a smart meter. We oblige and install a regular mechanical meter. Of course, there is a monthly fee to manually read it...
 
Hv&Lv said:
Why don't you like it?
We have some customers that absolutely do not want a smart meter. We oblige and install a regular mechanical meter. Of course, there is a monthly fee to manually read it...
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I see, I don't care how smart the meter is, I was talking about getting rid of it altogether, has a tendency to make the cost of energy much less:happyyes:
 
Would it be a consideration and make more sense to just abandon the existing all together and simply install a new grounding system per the current code requirements instead of attempting to incorporated the existing?
In my own home there was 1 ground rod driven into the basement floor right below the panel and then there was a connection to a copper water pipe closest to the panel.
I abandoned them and drove (2) ground rod per code requirements on the outside of my house and ran a copper conductor across the basement to the water meter bonding it on one side of the meter jumpering it to the incomng ide of the water supply.
 
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