Grounding multiple disconnects

[ivsenroute]

What method do you use when installing the grounding electrode system where the disconnects are grouped together?

Do you run the GEC from the closest panel to the electrode then using the internal terminal bars of the disconnects connect the other ones the the first one like a daisy chain?

Do you run the GEC from the farthest disconnect then crimp the other grounds coming from the other panels to the GEC like it is a trunk line (tap method)?

Install a nice thick 1/4 grounding plate (busbar) at a central location?

Another method?

What is popular in your area.

 

[cschmid]

Actually it depends on the situation my favorite is using a grounding bus..it has the best options..

 

[infinity]

I prefer this method with a couple of split bolts for the taps:

 

[ivsenroute]

Are split bolts allowed for this type of connection? If the taps are still part of the GEC then split bolts would not be allowed.

 

[ivsenroute]

I am asking this because there was a change from 2005 to 2008 in this section with the 2008 being more restrictive.

Are there split bolts that are listed as grounding and bonding equipment?

 

[infinity]

Taps to the GEC are permitted as long as the GEC remains unbroken. I would assume that split bolts are listed for connection of bonding jumpers to a GEC but I can't say for sure.

250.64(D) Service with Multiple Disconnecting Means Enclosures. Where a service consists of more than a single enclosure as permitted in 230.71(A), grounding electrode connections shall be made in accordance with (D)(1), (D)(2), or (D)(3).
(1) Grounding Electrode Conductor Taps. Where the service is installed as permitted by 230.40, Exception No. 2, a common grounding electrode conductor and grounding electrode conductor taps shall be installed. 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 conductor(s). Where the service-entrance conductors connect directly to a service drop or service lateral, the common grounding electrode conductor shall be sized in accordance with Table 250.66, Note 1. A tap conductor shall extend to the inside of each service disconnecting means enclosure. The grounding electrode conductor taps shall be sized in accordance with 250.66 for the largest conductor serving the individual enclosure. The tap conductors shall be connected to the common grounding electrode conductor by exothermic welding or with connectors listed as grounding and bonding equipment in such a manner that the common grounding electrode conductor remains without a splice or joint.

 

[ivsenroute]

They are marketed that way. They probably are.

 

[augie47]

Shortly after I noted that "listed for grounding" wording I contacted Burndy and they sent documentation on a number of their products that were "approved" including split bolts.

 

[shortcircuit2]

In exibit 250.27 in post #3 the GEC doesn't connect to the Bus that the grounded service conductor lands...only the tap does. Wouldn't this be a violation of 250.24(A)(1)

shortcircuit2

 

[augie47]

I am asking this because there was a change from 2005 to 2008 in this section with the 2008 being more restrictive.

Are there split bolts that are listed as grounding and bonding equipment?

When that Code change was enacted I contacted Burndy and received an e-mail showing all there split bolts were listed for grounding applications.