Galvinaized 90 with PVC

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Do I have to bond, and how do I when using galvanized 90's with pvc pipe.
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Yes, unless the 90 is covered with 18" of earth or 2" of concrete. 250.86 Exception #3. As far as how to do it, there is no good way.
Don
 
I've never had to bond a 90 like that, but I would probably use a grounding clamp like those used on water lines for services.
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That is the easy part. Where and how do you run the bond wire?
Don
 
I always assumed the contractor would direct burry a bare ground wire (running along with the PVC) to the next metal elbow. If the last section of conduit is metal, and lands on a panel or disconnect, thats the "where".

Steve
 
:oops: Well Don, now that's a good question. I suppose if an AHJ forced me to bond one of these elbows, my only choice would be to run a properly sized bare copper conductor to the grounding grid for the building. (I think this discussion proves that running PVC above ground with metallic elbows is just not a good idea!!!)
What do you think?
 
Steve,
But then we would have an EGC that is not run in the same raceway as the circuit conductors. 300.3(B).
Don
 
ramdiesel,
my only choice would be to run a properly sized bare copper conductor to the grounding grid for the building.
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It would have to connect to the point where the circuit EGC originates.
(I think this discussion proves that running PVC above ground with metallic elbows is just not a good idea!!!)
What do you think?
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I think that in many cases, that the conductors cannot be installed without damage unless you use a rigid 90.
Don
 
Quote:
(I think this discussion proves that running PVC above ground with metallic elbows is just not a good idea!!!)
What do you think?

I think that in many cases, that the conductors cannot be installed without damage unless you use a rigid 90.
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Don
I agree! What I meant was that, in general, running PVC raceway above ground with exposed metallic elbows is just not very practical. Thats why I always switch to metallic raceways above grade.
 
don_resqcapt19 said:
Steve,
But then we would have an EGC that is not run in the same raceway as the circuit conductors. 300.3(B).
Don
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How would you apply 300.3(B) when I bond two raceways together where I have flex between them at the building expansion joints? I have always put a pipe clamp on both ends of my EMT and the appropriate jumper between them. Bonding 90's, as mentioned, is the same concept.

I'm going to go out on a limb and say 300.3(B) does not apply because I'm bonding the raceway, and not the equipment. So therefore, it's not part of the circuit.
 
Paul,
How would you apply 300.3(B) when I bond two raceways together where I have flex between them at the building expansion joints?
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300.3(B) provides for your installation with a reference to 250.102(E). I'm assuming that in the case of isolated rigid 90's you would not be able to comply with the 6' maximum length in 250.102(E).
Don
 
I was talking about below ground conduit runs where the top of the elbows don't have the required depth to not be bonded. Or sections that are metal conduit that comes out of the ground. So maybe we aren't exactly on the same page :) (Runs completely above ground were also mentioned).

But 2501.102E does provide an exception where you aren't limited to 6', and I think it applies to just these cases.

Steve
 
Steve,
But 2501.102E does provide an exception where you aren't limited to 6', and I think it applies to just these cases.
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There is an exception, but it is limited and only applies at outside poles.
Exception: An equipment bonding jumper longer than 1.8 m (6 ft) shall be permitted at outside pole locations for the purpose of bonding or grounding isolated sections of metal raceways or elbows installed in exposed risers of metal conduit or other metal raceway.
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Don
 
There is an exception, but it is limited and only applies at outside poles.
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Can the contractor drives a 3' stick of 2"x2" into the ground and call it a pole? :)

Otherwise, we have the lesser of two evils: Either ignore the bonding completely, or pretend there is a pole where there isn't one.
 
Steve,
Otherwise, we have the lesser of two evils: Either ignore the bonding completely, or pretend there is a pole where there isn't one.
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You can use metallic raceways and eliminte the bonding problem.
Don
 
Don, slight change of subject. Exhibit 250.43 seems like a poor example. Most motors have a ground connection provided inside the box as well as most combination starters. It would be more cost efficient to run wire internally in this example. Now above they talk about hazardous locations, but the flex they are showing I do not think is approved for any hazardous location.

Educate me. Please!
 
Larry,
Most motors have a ground connection provided inside the box as well as most combination starters. It would be more cost efficient to run wire internally in this example.
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Plant specs where I am at require both an internal EGC and and external bonding jumper for the sealtight.
Now above they talk about hazardous locations, but the flex they are showing I do not think is approved for any hazardous location.
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Flexible metal conduit is permitted in Class I, Divison 2 locations. 501.10(B)(2)(2).
Don
 
Don said:
Plant specs where I am at require both an internal EGC and and external bonding jumper for the sealtight.
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Open mouth and insert foot. Thanks for ref 501.10(B)(2)(2).

We use the orange non metallic sealtight. What type do you use? I don't see any advantage to using an external bond unless it is metal.

I am accustomed to paint fumes and solvents and didn't take the time to investigate.
 
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