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Discussion Starter · #1 ·
I am getting ready to run a 60 amp circuit to a detached garage.
The garage contains a ufer ground.

Do I need to install a rod as well?
Can I use a #10 wire to hit the ufer, or does it need to be larger?

Thanks.
 

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Professional Nit Picker
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(3) Concrete-Encased Electrode.
A concrete-encased electrode shall consist of at least 6.0 m (20 ft) of either
(1) or (2):
(1) One or more bare or zinc galvanized or other electrically conductive coated steel reinforcing bars or rods of not less than 13 mm (1⁄2 in.) in diameter, installed in one continuous 6.0 m (20 ft) length, or if in multiple
pieces connected together by the usual steel tie wires, exothermic welding, welding, or other effective means to create a 6.0 m (20 ft) or greater length; or
(2)] Bare copper conductor not smaller than 4 AWG Metallic components shall be encased by at least 50 mm (2 in.) of concrete and shall be located horizontally within that portion of a concrete foundation or footing that is in direct contact with the earth or within vertical foundations or structural components or members that are in direct contact with the earth. If multiple
concrete-encased electrodes are present at a building or structure, it shall be permissible to bond only one into the grounding electrode system.
 

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Electrical Simpleton
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(3) Concrete-Encased Electrode.
A concrete-encased electrode shall consist of at least 6.0 m (20 ft) of either
(1) or (2):
(1) One or more bare or zinc galvanized or other electrically conductive coated steel reinforcing bars or rods of not less than 13 mm (1⁄2 in.) in diameter, installed in one continuous 6.0 m (20 ft) length, or if in multiple
pieces connected together by the usual steel tie wires, exothermic welding, welding, or other effective means to create a 6.0 m (20 ft) or greater length; or
(2)] Bare copper conductor not smaller than 4 AWG Metallic components shall be encased by at least 50 mm (2 in.) of concrete and shall be located horizontally within that portion of a concrete foundation or footing that is in direct contact with the earth or within vertical foundations or structural components or members that are in direct contact with the earth. If multiple
concrete-encased electrodes are present at a building or structure, it shall be permissible to bond only one into the grounding electrode system.
I could be missing something but if you install 20 feet of 4 cu as the grounding electrode the grounding electrode conductor would still be able to comply with:

250.66(B)Connections to Concrete-Encased Electrodes.
Where the grounding electrode conductor is connected to a
concrete-encased electrode as permitted in 250.52(A)(3),
that portion of the conductor that is the sole connection to
the grounding electrode shall not be required to be larger
than 4 AWG copper wire.

Based on 250.66 the size of the grounding electrode conductor would be permitted to be no smaller than 8awg cu as long as the feeder ungrounded conductors were 2 cu or smaller.

Pete
 

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I could be missing something but if you install 20 feet of 4 cu as the grounding electrode the grounding electrode conductor would still be able to comply with:

250.66(B)Connections to Concrete-Encased Electrodes.
Where the grounding electrode conductor is connected to a
concrete-encased electrode as permitted in 250.52(A)(3),
that portion of the conductor that is the sole connection to
the grounding electrode shall not be required to be larger
than 4 AWG copper wire.

Based on 250.66 the size of the grounding electrode conductor would be permitted to be no smaller than 8awg cu as long as the feeder ungrounded conductors were 2 cu or smaller.

Pete
Well , after reading the sections slowly, carefully one word at a time I can see your point. I am just accustomed to seeing the # 4 bare ran long enough to get to the service ( feeder) disconnecting means. That or a piece of rebar stubbed out to attach the GEC to.
 

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Electrical Contractor
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Well , after reading the sections slowly, carefully one word at a time I can see your point. I am just accustomed to seeing the # 4 bare ran long enough to get to the service ( feeder) disconnecting means. That or a piece of rebar stubbed out to attach the GEC to.
There's a lot of disagreement on the connection issue. We always just stub out the rebar and connect the #4 to that. The 2014 code clears that one up and makes it clear that it's okay to stub out the rebar.
 

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Electrical Simpleton
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There's a lot of disagreement on the connection issue. We always just stub out the rebar and connect the #4 to that. The 2014 code clears that one up and makes it clear that it's okay to stub out the rebar.
The #4 is most commonly used but it isn't required in all situations if it is actually the grounding electrode conductor.

Based upon the size of your service entrance and/or feeder conductors the GEC could be smaller.

Pete
 

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I am getting ready to run a 60 amp circuit to a detached garage.
The garage contains a ufer ground.

Do I need to install a rod as well?
Can I use a #10 wire to hit the ufer, or does it need to be larger?

Thanks.
# 6. I like the ufer but others have said that a strike can pop the crete. I don't believe that. In those cases most probably it was weakly mixed crete.
 

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Discussion Starter · #11 ·
are you an electrician?
No, why do you ask?:whistling2:

Maybe I should have just called you!

Heading back to the wood shop to install the buck boost transformers this weekend.
 
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