Bare copper grounding conductor in EMT

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gatorgep

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The AHJ at a recent inspection stated that the installation of a 3/0 bare copper conductor in EMT Conduit between grounding bars in Tele/Data rooms is a code violation. He is using Articles 250.64 (E) "Where raceway is used as protection for a grounding electrode conductor, the installation shal comply with the requirements of the appropriate raceway article." and 358.12 (6) " Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action." as the specific code references to back up his argument.
Are these the appropriate code references and interpretation?
 
I don't buy it. 'Course, I may be wrong. 250.64 is for grounding electrode conductors, & from your post you are describing grounding for communications circuits. I don't believe it's a gec. Article 800.100 might apply instead. If so, see 800.100(A)(1) & (6). JMHO.
 
First off I don't agree with the argument that you can't have a bare copper EGC conductor installed in a conduit. 250.148 requires that if we have an EGC run into a box and the circuit conductors are spliced or terminated on a device int he box we must also connect the copper EGC directly to the metal box. If there was a problem with copper being in direct contact with a galvanized metal pipe or box this section would not make sense.

Second 250.64 regulates the installation of the grounding electrode conductor, which the conductor you describing is not.

Section 800.100(A)(1) Does require the grounding conductor for communications equipment to be insulated so this section should have been the one the inspector cited.

Chris
 
I think that 250.118 allows it.

250.118 Types of Equipment Grounding Conductors

The equipment grounding conductor run with or enclosing the circuit conductors shall be one or more or a combination of the following:

(1) A copper, aluminum, or copper-clad aluminum conductor. This conductor shall be solid or stranded; insulated, covered, or bare; and in the form of a wire or a busbar of any shape.

250.62 Grounding Electrode Conductor Material
The grounding electrode conductor shall be of copper, aluminum, or copper-clad aluminum. The material selected shall be resistant to any corrosive condition existing at the installation or shall be suitably protected against corrosion. The conductor shall be solid or stranded, insulated, covered, or bare.

Edit to add 250.62
 
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electricalperson said:
so we have to put antioxidant when we bond boxes?
Click to expand...

And now we'll have to insulate all the bare grounds in the non painted back boxes.
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gatorgep said:
The AHJ at a recent inspection stated that the installation of a 3/0 bare copper conductor in EMT Conduit between grounding bars in Tele/Data rooms is a code violation. He is using Articles 250.64 (E) "Where raceway is used as protection for a grounding electrode conductor, the installation shal comply with the requirements of the appropriate raceway article." and 358.12 (6) " Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action." as the specific code references to back up his argument.
Are these the appropriate code references and interpretation?
Click to expand...

Another guy that went to a seminar and thought he learned something.
I would not change the installation.
Remind the inspector that an electrolyte must be present to have a galvanic reaction.
I dont think you are going to have any risk of a constant moisture or acid in your data room.
 
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