Subpanel in detached garage

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Eagle126

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I'm installing a 60 amp 4 wire subpanel seperating the neutral and ground in a detached garage at a residential home. Do i need to install a seperate ground rod at that subpanel location and if so am i required to install 2 ground rods just like i would under the main meter socket?
 
You'll need to install a GES. It does not have to be ground rods. In fact if the building is new and has 20' or more of 1/2" or larger rebar in the footing then you must use the CEE.
 
Everyone keeps saying you have to install (2) Ground Rods.
Not correct if you can verify (1) Rod is less than 25 ohms resistance to Ground.
But that usually doesnt happen so drive (2) so you wont have to go back and drive a 2nd one later. I've never had a ground rod tested by an inspector that was less than 25 ohms, so I asked one day, and he indicated he hadnt tested one yet that was either.
That pretty much led me to installing 2 to begin with from that point on.
 
infinity said:
In fact if the building is new and has 20' or more of 1/2" or larger rebar in the footing then you must use the CEE.
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What if the contractors who poured the slab did not bring a section of the rebar out of the concrete for the GES connection?
 
I think at this point we all realize that 2 rods are the norm but if we 25 ohms with one that will comply. It is easier just to say 2 rods. We don't even need rods for that matter. We can have a CEE or any of the other qualifying electrodes.
 
Jon456 said:
What if the contractors who poured the slab did not bring a section of the rebar out of the concrete for the GES connection?
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250.50 Grounding Electrode System. All grounding electrodes
as described in 250.52(A)(1) through (A)(7) that are
present at each building or structure served shall be bonded
together to form the grounding electrode system. Where
none of these grounding electrodes exist, one or more of
the grounding electrodes specified in 250.52(A)(4) through
(A)(8) shall be installed and used.

Exception: Concrete-encased electrodes of existing buildings
or structures shall not be required to be part of the
grounding electrode system where the steel reinforcing bars
or rods are not accessible for use without disturbing the
concrete.

 
jumper said:
Exception: Concrete-encased electrodes of existing buildings
or structures shall not be required to be part of the
grounding electrode system where the steel reinforcing bars
or rods are not accessible for use without disturbing the
concrete.
Click to expand...

Many areas would make you chop up the concrete if it is a new structure.
 
jumper said:
Mebbe, but I doubt it. It would require a Civil Engineer to say it was okay and I think most Building and Plans Departments would just say " oh well".

I am not saying it is right, but cutting up a footer would be a rare thing.
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I have heard members say that the have seen it done.
 
When the ufer gets missed, one of our inspectors here lets us dig a trench as deep as the footing next to the footing and lay 20' of #4 in it. Then cover with concrete.

Anybody else get the same workaround when the ufer gets forgotten?
 
jumper said:
Exception: Concrete-encased electrodes of existing buildings or structures shall not be required to be part of the grounding electrode system where the steel reinforcing bars or rods are not accessible for use without disturbing the concrete.
Click to expand...
I'm familiar with the exception, however that specifically states "existing buildings or structures". Hence my question about what to do with new construction where the rebar was not left exposed for GES connection. Dennis realized the intent of my question. ;)
 
Jon456 said:
I'm familiar with the exception, however that specifically states "existing buildings or structures". Hence my question about what to do with new construction where the rebar was not left exposed for GES connection. Dennis realized the intent of my question. ;)
Click to expand...

It would be the EC's responsibility to get there before the footing is poured and install the connection to the CEE. Around here you won't pass the footing inspection without it. No passed footing inspection, no pour.
 
infinity said:
You'll need to install a GES. It does not have to be ground rods. In fact if the building is new and has 20' or more of 1/2" or larger rebar in the footing then you must use the CEE.
Click to expand...
This is the best and correct answer. We need to get away from the ground rod thing. Think GES and that covers it all.
 
He in Indiana this code was changed to say "if made available" if it wasn't we are not required to connect, so it's kind of left up to the builder if they want a CEE or not.

While on the other hand some inspectors have tried to make the concrete guys turn up a piece of re-bar out of the footer then make us connect to it, its not really enforceable here with state wide codes.
 
Cow said:
When the ufer gets missed, one of our inspectors here lets us dig a trench as deep as the footing next to the footing and lay 20' of #4 in it. Then cover with concrete.

Anybody else get the same workaround when the ufer gets forgotten?
Click to expand...
I'm pretty sure that is compliant under any circumstances. Codebook is out in the truck but there is something that says if you have multiple spots that meet the rules for a CCE you are only required to use one of them.
 
infinity said:
It would be the EC's responsibility to get there before the footing is poured and install the connection to the CEE. Around here you won't pass the footing inspection without it. No passed footing inspection, no pour.
Click to expand...
Sort of like that here, but the concrete contractor often provides and installs the provision needed for the EC to use the CCE. In many cases the electrical contract has not been let at the time the footings are poured.
 
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