Bldg steel concrete encased electrode

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hhsting

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Glen bunie, md, us
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Please note we are still in NEC 2014. So any references please only NEC 2014.

I am going to have brand new building, nothing is existing and plans show building steel is per NEC 2014 Section 250.52(A)(2)(2) which requires hold down bolts connected to concrete encased electrode which should be per NEC 2014 section 250.52(A)(3).

Attached sketch shows one grounding electrode conductor to that building steel. However do I also need separate grounding electrode conductor to concrete encased electrode as shown in attached sketch with Dotted line or is concrete encased electrode considered bonded to grounding electrode system thru hold down bolts? Can anyone here help?




587121f5263bf3abc27b42e263cd3028.jpg
 

augie47

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Tennessee
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IMO, the separate conductor is not needed. '04, 250.52(A)(2) recognizes building steel with j bolts connected to the UFER as an electrode so you have electrodes interconnected,.
 

infinity

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IMO, the separate conductor is not needed. '04, 250.52(A)(2) recognizes building steel with j bolts connected to the UFER as an electrode so you have electrodes interconnected,.
I agree and if you wanted an extra conductor you would not need a GEC run all the way back to the service disconnect since a bonding jumper between the two is all that you would install.
 

kwired

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NE Nebraska
IMO, the separate conductor is not needed. '04, 250.52(A)(2) recognizes building steel with j bolts connected to the UFER as an electrode so you have electrodes interconnected,.
Just trying to further clarify here.

If the J bolts are indeed tied to the reinforcing bars used to help make up the CEE. Think just steel ties like used for tying rebar together are sufficient enough.

CEE with rebar but not tied to the J bolts would need additional bonding between them and the building steel or at least one J bolt somehow.
 

SSDriver

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California
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Electrician
That is usually fine and is to code. The code does recognize metal tie wire as an approved method between the metal rebar. But you do need a listed connector going to your GEC. However I usually run a ground clamp with bare wire to the main steel cage and j-bolt. It looks much better to everyone else.

250.52 A(3) said:
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
 
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