Hypothetical ground/bonding question

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ritelec

ritelec

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Jersey
Lets say... service lateral.

There's a utility pole.
Conductors come down the pole to a MOCP device mounted on the pole.

The neutral is bonded to the enclosure. There are also two ground rods driven and the grounding electrode conductor from them is connected to the bonded neutral in that enclosure.

The service conductors (feeder) are run underground to a dwelling unit. (phase 1,2,N,egc) In the dwelling, do all grounding electrodes and H2O system now just get connected to the EGC bar only and NOT to the floating neutral?

OR would one have to some how get the dwelling grounding electrode conductor from dwelling to the main out at the pole?

OR would one use two ground rods and ground and bond the neutral at the pole and , then run 3 conductor to the dwelling (no egc) and bond and ground it again using the ground electrodes on premises and additional ground rods?


I'm thinking there would be a egc run from the utility pole and all existing grounding electrodes in the dwelling would go to the equipment ground in the panel.


Wondering... Thank you
 
ritelec said:
Lets say... service lateral.

There's a utility pole.
Conductors come down the pole to a MOCP device mounted on the pole.

The neutral is bonded to the enclosure. There are also two ground rods driven and the grounding electrode conductor from them is connected to the bonded neutral in that enclosure.

The service conductors (feeder) are run underground to a dwelling unit. (phase 1,2,N,egc) In the dwelling, do all grounding electrodes and H2O system now just get connected to the EGC bar only and NOT to the floating neutral?

OR would one have to some how get the dwelling grounding electrode conductor from dwelling to the main out at the pole?

OR would one use two ground rods and ground and bond the neutral at the pole and , then run 3 conductor to the dwelling (no egc) and bond and ground it again using the ground electrodes on premises and additional ground rods?


I'm thinking there would be a egc run from the utility pole and all existing grounding electrodes in the dwelling would go to the equipment ground in the panel.


Wondering... Thank you
Click to expand...
From my understanding from the meter/main at the pole you would have to run a EGC. Than also have a grounding electrode system for the dwelling and would land the GEC on the EGC bar.

If one were to terminate the GEC on the “floating” neutral in the house panel after the service disconnect you could have undesired objectionable current and get really nasty in the event of a lost neutral.

Correct me if I am misleading anyone.
 
ritelec said:
Lets say... service lateral.

There's a utility pole.
Conductors come down the pole to a MOCP device mounted on the pole.

The neutral is bonded to the enclosure. There are also two ground rods driven and the grounding electrode conductor from them is connected to the bonded neutral in that enclosure.

The service conductors (feeder) are run underground to a dwelling unit. (phase 1,2,N,egc) In the dwelling, do all grounding electrodes and H2O system now just get connected to the EGC bar only and NOT to the floating neutral?

OR would one have to some how get the dwelling grounding electrode conductor from dwelling to the main out at the pole?

OR would one use two ground rods and ground and bond the neutral at the pole and , then run 3 conductor to the dwelling (no egc) and bond and ground it again using the ground electrodes on premises and additional ground rods?


I'm thinking there would be a egc run from the utility pole and all existing grounding electrodes in the dwelling would go to the equipment ground in the panel.


Wondering... Thank you
Click to expand...
Like DSG said . You keep the neutral and eg separate. You also install two more grd rods in acordance with 250.50

I'll give you an example of objectional current that dsg319 mentioned . If you bonded every thing to the neutral including the water lines. phones, etc...
If you had a basement with old cast iron drains, copper water lines. In some cases that will be a better return path then the neutral. So if you're taking a shower when the phone rings you may fill a shock in the shower. (Just an example their are many scenarios)
 
ritelec said:
The service conductors (feeder) are run underground to a dwelling unit. (phase 1,2,N,egc) In the dwelling, do all grounding electrodes and H2O system now just get connected to the EGC bar only and NOT to the floating neutral?
Click to expand...
Normally, that's correct. The panel in the house would be wired like any sub-panel.

OR would one have to some how get the dwelling grounding electrode conductor from dwelling to the main out at the pole?
Click to expand...
The pole and house each need electrodes, and the EGC is the interconnection.

OR would one use two ground rods and ground and bond the neutral at the pole and , then run 3 conductor to the dwelling (no egc) and bond and ground it again using the ground electrodes on premises and additional ground rods?
Click to expand...
This is a viable option, but I believe the device on the pole must be a switch, not OCP.

I'm thinking there would be a egc run from the utility pole and all existing grounding electrodes in the dwelling would go to the equipment ground in the panel.
Click to expand...
In either case, each structure requires an electrode system.
 
ptonsparky said:
Depends. What NEC are you under? How is it labeled?

2020 NEC 230.85
Click to expand...
That’s a good point with the new emergency disconnect rule. I personally would just do a meter main on the side of the house but I wonder if you could have the emergency disconnect say remote (50ft away) mounted on a pole. Than would you be able to get away with 3wire and no EGC? Since it is serving as a emergency disco only and having the service disconnect at the house.
 
Dsg319 said:
That’s a good point with the new emergency disconnect rule. I personally would just do a meter main on the side of the house but I wonder if you could have the emergency disconnect say remote (50ft away) mounted on a pole. Than would you be able to get away with 3wire and no EGC? Since it is serving as a emergency disco only and having the service disconnect at the house.
Click to expand...
We are allowed that. Basically had it for years without the signage.
 
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