GEC with 2 Disconnects

[psimmond]

Does the picture show 250.62 (D)(1)(3): GEC tap to common electrode conductor via busbar connection? (This seems more like a jumper than a tap.)

Second question: If a separate GEC were run from each disconnect and both were clamped to a ground rod, you would still only need to run a single 6 AWG copper jumper from that ground rod to a second supplemental rod, right? (This is assuming a scenario where two are needed to achieve 25 ohms or less.)

 

[infinity]

The tap should be outside of the first 200 amp panel. You just use a split bolt.

Second question: yes.

 

[psimmond]

The tap should be outside of the first 200 amp panel. You just use a split bolt.

Second question: yes.

Oops, my OP should have said 250.64(D)(1)(3).

Here's the way I interpreted it:

250.64(D)(1)(1) would be running a short conductor from busbar in Disconnect B to continuous GEC in Disconnect A and connecting them with an exothermic weld.
250.64(D)(1)(2) would be running a short conductor from busbar in Disconnect B to continuous GEC in Disconnect A and connecting them with a split bolt.
250.64(D)(1)(3) would be running a short conductor from busbar in Disconnect B to busbar in Disconnect A (where continuous GEC originates).

Do you think the split bolt is just one of three methods?

 

[psimmond]

The tap should be outside of the first 200 amp panel. You just use a split bolt.

Second question: yes.

I've given this more thought and I think I've been looking at this all wrong. I guess the picture doesn't show a tap. It just shows what might be called a jumper from Disconnect A to B. In a setup like this, you'd probably use the jumper as shown in the picture rather than a tap, right?

 

[infinity]

I've given this more thought and I think I've been looking at this all wrong. I guess the picture doesn't show a tap. It just shows what might be called a jumper from Disconnect A to B. In a setup like this, you'd probably use the jumper as shown in the picture rather than a tap, right?

I don't have access to the codebook at the moment but the tap method is code complaint. From my recollection the jumper from one piece of equipment to the other is not. So if you went GEC from Disconnect A to the electrode and spliced on a bonding jumper to disconnect B that would be code compliant. All of the conductors would be #6 AWG.

 

[jaggedben]

Does the picture show 250.62 (D)(1)(3): GEC tap to common electrode conductor via busbar connection? (This seems more like a jumper than a tap.)

The GEC tap from the disco on the right should be tapped to the GEC to the rod, not landed on the ground bar.

Oops, my OP should have said 250.64(D)(1)(3).

Here's the way I interpreted it:

250.64(D)(1)(1) would be running a short conductor from busbar in Disconnect B to continuous GEC in Disconnect A and connecting them with an exothermic weld.
250.64(D)(1)(2) would be running a short conductor from busbar in Disconnect B to continuous GEC in Disconnect A and connecting them with a split bolt.
250.64(D)(1)(3) would be running a short conductor from busbar in Disconnect B to busbar in Disconnect A (where continuous GEC originates).

Do you think the split bolt is just one of three methods?

Split bolt or exothermic weld to tap one from another (or in other words make two GECs into one) would be option (1).
Option 2 is running separate GECs from each disconnect to the first rod.
Option 3 is a single GEC run from somewhere upstream of both disconnects, such as the meter socket, or a trough or transition box. (Utilities may not allow it in meters, and AHJs may not allow it in enclosures sealed by the utility, but the NEC doesn't require meters or sealing so it considers this an option.)

 

[psimmond]

Thanks! Is there code that would prevent the setup in the picture but instead of terminating the short GEC jumper to the grounding busbar in Disconnect A, you connect it via a split bolt to the continuous GEC right after it leaves its busbar. It seems you could argue it would be practically no different from 250.64(D)(1)(2).

 

[psimmond]

Thanks! Is there code that would prevent the setup in the picture but instead of terminating the short GEC jumper to the grounding busbar in Disconnect A, you connect it via a split bolt to the continuous GEC right after it leaves its busbar. It seems you could argue it would be practically no different from 250.64(D)(1)(2).

I guess I'm asking if 250.64(D)(1)(2) allows the tap from Disconnect B to run across through the raceways and connect 'inside' Disconnect panel A (via split bolt).

 

[roger]

All the services I worked on in GA allowed the CEC to be landed in the meter can, so with that said why not use 250.64(D)(3)

 

[infinity]

I guess I'm asking if 250.64(D)(1)(2) allows the tap from Disconnect B to run across through the raceways and connect 'inside' Disconnect panel A (via split bolt).

It could be argued that the wording of 250.64(D)(1) would not permit the GEC to be run to one disconnect and then a tap to the other regardless of where that connection is made. It specifically states that a tap shall extend to the inside of each servcie disconnecting means enclosure. When the GEC and the taps are all the same size it seems silly to have to cut the GEC and add the taps to it.

250.64(D)(1) Common Grounding Electrode Conductor and Taps.
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 conductor(s) of each set of conductors that supplies the disconnecting means. If the service-entrance conductors connect directly to the overhead service
conductors, service drop, underground service conductors, or service lateral, the common grounding electrode conductor shall be sized in accordance with Table 250.66, note 1. A grounding electrode conductor tap shall extend to the inside of each disconnecting means enclosure. The grounding electrode conductor taps shall be sized in accordance with 250.66 for the largest service-entrance or feeder conductor serving the individual enclosure. The tap conductors shall be connected to the common grounding electrode conductor by one of the following methods in such a manner that the common grounding electrode conductor remains without a splice or joint:
(1) Exothermic welding.
(2) Connectors listed as grounding and bonding equipment