Does everyone use 300.5 for depth of GEC? Example between 2 ground rods away from the building.

Paul,

I do. Most people probably don't understand your question because that is one of the least enforced codes in Florida.

If they can't bury the GEC to code, then I make them strap it to the side of the building, from one ground rod to the next, and I consider that protected.

Throwing some dirt, cypress mulch, or pine bark on top of the conductor is not adequate, IMHO. In fact it is pretty lame.

Paul I also use the requirements of 300.5(D) as well as the requirements of 250.64(B)

Exhibit 250.25 in the handbook would be deceiving then wouldn't it?(ref 250.56)
Some might even question whether 300.5 actually applies to a single conductor



Is a single conductor a "cable"?
In that regard 300.5 is wrong because we also use it for USE
Do you apply column 1? (24")
Has anyone actually put city hubs on the rod and run RNC between them?

It is a great question if the rod is not right next to the building.

I completely agree the GEc needs to be rptoected from physical damage and 300.5 seems to be a resonable section to reference and use a a guide for determining what would be considered protected, however, attempts to get language into the NEC regarding this topic has failed the last three code cycles. Here are a few from the 2008 code cycle:

Bryan I think that the reason those proposals would not pass is because there is too much language, and it is too confusing. In reality we only need to add one last sentence (underlined below):



250.64 Grounding Electrode Conductor Installation.
Grounding electrode conductors shall be installed as specified in 250.64(A) through (F).

(A) Aluminum or Copper-Clad Aluminum Conductors. Bare aluminum or copper-clad aluminum grounding conductors shall not be used where in direct contact with masonry or the earth or where subject to corrosive conditions. Where used outside, aluminum or copper-clad aluminum grounding conductors shall not be terminated within 450 mm (18 in.) of the earth.

(B) Securing and Protection Against Physical Damage. Where exposed, a grounding electrode conductor or its enclosure shall be securely fastened to the surface on which it is carried. A 4 AWG or larger copper or aluminum grounding electrode conductor shall be protected where exposed to physical damage. A 6 AWG grounding electrode conductor that is free from exposure to physical damage shall be permitted to be run along the surface of the building construction without metal covering or protection where it is securely fastened to the construction; otherwise, it shall be in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, electrical metallic tubing, or cable armor. Grounding electrode conductors smaller than 6 AWG shall be in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, electrical metallic tubing, or cable armor.

(C) Continuous. Grounding electrode conductor(s) shall be installed in one continuous length without a splice or joint except as permitted in (1) through (4):

(1) Splicing shall be permitted only by irreversible compression-type connectors listed as grounding and bonding equipment or by the exothermic welding process.

(2) Sections of busbars shall be permitted to be connected together to form a grounding electrode conductor.

(3) Bonding jumper(s) from grounding electrode(s) and grounding electrode conductor(s) shall be permitted to be connected to an aluminum or copper busbar not less than 6 mm × 50 mm (¼ in. × 2 in.). The busbar shall be securely fastened and shall be installed in an accessible location. Connections shall be made by a listed connector or by the exothermic welding process.

(4) Where aluminum busbars are used, the installation shall comply with 250.64(A).

(D) Grounding Electrode Conductor Taps. Where a service consists of more than a single enclosure as permitted in 230.71(A), it shall be permitted to connect taps to the common grounding electrode conductor. Each such tap conductor shall extend to the inside of each such enclosure. The common grounding electrode conductor shall be sized in accordance with 250.66, based on the sum of the circular mil area of the largest ungrounded service entrance conductors. Where more than one set of service entrance conductors as permitted by 230.40, Exception No. 2 connect directly to a service drop or lateral, the common grounding electrode conductor shall be sized in accordance with Table 250.66 Note 1. The tap conductors shall be permitted to be sized in accordance with the grounding electrode conductors specified in 250.66 for the largest conductor serving the respective enclosures. The tap conductors shall be connected to the common grounding electrode conductor in such a manner that the common grounding electrode conductor remains without a splice or joint.

(E) Enclosures for Grounding Electrode Conductors. Ferrous metal enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode and shall be securely fastened to the ground clamp or fitting. Nonferrous metal enclosures shall not be required to be electrically continuous. Ferrous metal enclosures that are not physically continuous from cabinets or equipment to the grounding electrode shall be made electrically continuous by bonding each end of the raceway or enclosure to the grounding electrode conductor. Bonding shall apply at each end and to all intervening ferrous raceways, boxes, and enclosures between the service equipment and the grounding electrode. The bonding jumper for a grounding electrode conductor raceway or cable armor shall be the same size as, or larger than, the required enclosed grounding electrode conductor. Where a raceway is used as protection for a grounding electrode conductor, the installation shall comply with the requirements of the appropriate raceway article.

(F) To Electrode(s). A grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system, or to one or more grounding electrode(s) individually, or to the aluminum or copper busbar as permitted in 250.64(C). The grounding electrode conductor shall be sized for the largest grounding electrode conductor required among all the electrodes connected to it. Where the grouding electrode conductor is run below grade, it shall comply with the minimum burial depth per Table 300.5.




Reason:

There is confusion in the industry as to the required depth of the conductor, considering that the required depth of a ground ring is 30". So it is odd that the "conductor" run between electrodes, which would not normally carry current, could be less than that amount.

"Ground Ring. The ground ring shall be buried at a depth below the earth’s surface of not less than 750 mm (30 in.)."



SOMETHING TO THINK ABOUT.

There us no requirement in the NEC for the GEC to comply with 300.5 Being that this state has a uniform code and a process for code amendments, there should be no jurisdiction or inspector that would require more or something different than the code itself.

90.1(b)


Maybe we should read Charlie's rule for Reading the NEC:
The idea is that after all...the code says exactly what it should say.

Mike, I believe that there is a minimum cover requirement for the grounding electrode conductor.

1) GEC is a conductor.
2) The table covers installations between "0 to 600 Volts"

Maybe he is reading the actual rule that references the table. The GEC is not a cable or conduit or other raceway(s)

The grounding electrode conductor is a conductor and the table applies if one chooses to bury it. What Mike pointed out is not specific to the table.