grounding electrode conductor in pvc to rigid

[nickelec]

I think a little more information is needed if you stub out of the ground with a price of rmc on both ends why can't one use gorunding bushings to bond the conduit?

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[ActionDave]

I think a little more information is needed if you stub out of the ground with a price of rmc on both ends why can't one use gorunding bushings to bond the conduit?

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Because you would not be able to bond both ends of both pieces of metallic conduit.

 

[roger]

I think a little more information is needed if you stub out of the ground with a price of rmc on both ends why can't one use gorunding bushings to bond the conduit?

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Read 250.64(E)

Roger

 

[wwhitney]

Because you would not be able to bond both ends of both pieces of metallic conduit.

If both ends of the PVC portion are in accessible locations, then you could put a metal type C-condulet at each end of the PVC, tap a hole in the back of the condulet, and put in a lay-in lug to bond to the grounding electrode conductor as it passes through.

Cheers, Wayne

 

[infinity]

How does using PVC and RMC together get around 250.64(E)(1)?

 

[wwhitney]

How does using PVC and RMC together get around 250.64(E)(1)?

That section uses the phrase "electrically continuous." The bonding of each end of each segment to the GEC renders the segments "electrically continuous." If the intention was to require the RMC itself to be continuous, the wording would be different.

Cheers, Wayne

 

[don_resqcapt19]

That section uses the phrase "electrically continuous." The bonding of each end of each segment to the GEC renders the segments "electrically continuous." If the intention was to require the RMC itself to be continuous, the wording would be different.

Cheers, Wayne

How would you make that bond with one end of the rigid 90 underground and connected to PVC conduit?

 

[infinity]

That section uses the phrase "electrically continuous." The bonding of each end of each segment to the GEC renders the segments "electrically continuous." If the intention was to require the RMC itself to be continuous, the wording would be different.

Cheers, Wayne

I the way I read it it says that the ferrous raceway shall be electrically continuous not that it shall be made electrically continuous. IMO the RMC>PVC>RMC violates that section.

 

[wwhitney]

I the way I read it it says that the ferrous raceway shall be electrically continuous not that it shall be made electrically continuous. IMO the RMC>PVC>RMC violates that section.

If that were the intention, they would have left out the modifier "electrically" and just said the ferrous raceway shall be continuous. And unless there's some way to bond a ferrous raceway directly to a grounding electrode, the "electrical continuity" has to depend on the GEC at the electrode end. So why not in the middle?

Cheers, Wayne

 

[wwhitney]

How would you make that bond with one end of the rigid 90 underground and connected to PVC conduit?

I'm having trouble picturing a situation where the GEC has to go underground like that, but perhaps that's due to a narrowness of experience.

I can't think of any good, practical way to do it. You could set a manhole and use a type C condulet as previously suggested.

You could put an external bonding clamp on the end of the elbow, bring a bonding jumper up to grade alongside the elbow, and use a type T condulet on the above grade elbow end to bring the bonding jumper in and bond to the GEC there. But perhaps that would violate the purpose of the requirement, even it meets the letter of the requirement. I'm not clear on the choke effect details.

You could run a bonding jumper alongside of the underground PVC conduit from metal elbow to metal elbow, but again, would that accomplish the goal of reducing the choke effect?

Cheers, Wayne

 

[roger]

I'm having trouble picturing a situation where the GEC has to go underground like that, but perhaps that's due to a narrowness of experience.

I can't think of any good, practical way to do it. You could set a manhole and use a type C condulet as previously suggested.

You could put an external bonding clamp on the end of the elbow, bring a bonding jumper up to grade alongside the elbow, and use a type T condulet on the above grade elbow end to bring the bonding jumper in and bond to the GEC there. But perhaps that would violate the purpose of the requirement, even it meets the letter of the requirement. I'm not clear on the choke effect details.

You could run a bonding jumper alongside of the underground PVC conduit from metal elbow to metal elbow, but again, would that accomplish the goal of reducing the choke effect?

Cheers, Wayne

Once again, the OP should ignore the spec and use PVC for the whole run. In all contract documents there is wording something like "this contractor is responsible for all applicable codes" and in this case that's what he would be doing.

A creative person can make this extremely difficult and expensive for no reason.

Roger