Meter/Disco Bonding

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infinity said:
The hub in that section is not for a Myers hub. A Myers hub is still held in place with a locknut. Now if it had a grounding locknut that might be a different story.
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augie47 said:
As I recall it goes back to the listing (you would need the listing category and a UL White Book). Not all hubs are listed as an acceptable grounding means for service conductors. That is why the hub in your picture has the provision for bonding. Per the UL listing, a bond jumper would be required.
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I see in the handbook it mentions UL 467 (Cat Code KDER). Just stating "threaded hub" is kind of misleading in the code. So I've gone full circle and now I understand. I'd still like to find the code reference that states only one side of a service raceway needs to bonded. Thanks for everyone's feedback on this thread.
 
As you aldready know, 250.92 requires electrical components containing service conductors be bonded. The meter and diaconenct are already bonded to the neutral so the metallic conduit is the only item needing bonding and if it's bonded omn either end that suffices.
FYI Here is a portion of KDER on hubs:
Grounding and Bonding Hubs — Grounding and bonding hubs are certified hubs (see DWTT) provided with a certified grounding or bonding locknut
 
quantum said:
I see in the handbook it mentions UL 467 (Cat Code KDER). Just stating "threaded hub" is kind of misleading in the code. So I've gone full circle and now I understand. I'd still like to find the code reference that states only one side of a service raceway needs to bonded. Thanks for everyone's feedback on this thread.
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I see it as confusing as well because the thing in your photo's is called a Myers "hub" but that's more of a trade name than a code description. If you look at this graphic you'll see that you're not bonding both ends because it's not necessary since the neutral is bonded in both pieces of equipment. All you want to do is bond the raceway with something other than a standard locknut at either end.

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infinity said:
I see it as confusing as well because the thing in your photo's is called a Myers "hub" but that's more of a trade name than a code description. If you look at this graphic you'll see that you're not bonding both ends because it's not necessary since the neutral is bonded in both pieces of equipment. All you want to do is bond the raceway with something other than a standard locknut at either end.
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I understand that, but I was curious if it was explicitly stated some place. The myers hub is sold and spec'd under that name, but it does not have the UL listing mentioned. Without that knowledge, just reading the code verbatim, you would think it fits the bill:

 
quantum said:
I understand that, but I was curious if it was explicitly stated some place. The myers hub is sold and spec'd under that name, but it does not have the UL listing mentioned. Without that knowledge, just reading the code verbatim, you would think it fits the bill:

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The hub you show in post #12 is a grounding hub as it has the ground tab and screw to attach a bonding jumper sized per 250.102 using a lug. This can be used for compliance with 250.92 for bonding of the metallic nipple. You only need one on one end as previously discussed. In your application the hub at the other end of the nipple could be a non-grounding hub or just use the grounding hub and leave the grounding tab unused.
Standard Myers hubs are made as "standard" grounding or specifically as a grounding hub (it has the attachment point for a bonding jumper). These are 2 separate NRTL listings.
 
texie said:
The hub you show in post #12 is a grounding hub as it has the ground tab and screw to attach a bonding jumper sized per 250.102 using a lug. This can be used for compliance with 250.92 for bonding of the metallic nipple. You only need one on one end as previously discussed. In your application the hub at the other end of the nipple could be a non-grounding hub or just use the grounding hub and leave the grounding tab unused.
Standard Myers hubs are made as "standard" grounding or specifically as a grounding hub (it has the attachment point for a bonding jumper). These are 2 separate NRTL listings.
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I agree, also the Myers hub at the top of the nipple is not required at all it could just be two locknuts and a bushing.
 
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