Bonding Conduits in an Enclosure

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quantum

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We have 12 RGS conduits entering/exiting a service disconnect (metallic enclosure) using myers hubs. Is it really necessary to bond these conduits to the ground bar since the enclosure is metallic? We will be doing so regardless, but if I understand correctly, we already have an electrically continuous raceway.
 
Hopefully I remember this correctly, if not someone will correct me :)
You mentioned "service" ...Your Myers hubs should be sufficient for any circuit having overcurrent protection.
Not all Myers hubs are listed for bonding of service raceways but thy are available with bonding lugs when used on service conduits
 
augie47 said:
Hopefully I remember this correctly, if not someone will correct me :)
You mentioned "service" ...Your Myers hubs should be sufficient for any circuit having overcurrent protection.
Not all Myers hubs are listed for bonding of service raceways but thy are available with bonding lugs when used on service conduits
Click to expand...

We always buy them with the grounding lug and we always bond them, my question is, is it really necessary? Our conduits are RGS and the service disconnect is metallic. Seems like bonding the conduits to the ground bar is redundant.
 
texie post this a few years back and it is still the case as I understand it:

hubs are covered under DWTT and are suitable for normal grounding. It does not mention use for compliance with 250.92, however if you look at "related products" in DWTT it refers you to KDER which specifically states that KDER covers compliance to 250.92 for grounding and bonding hubs (which are the hubs with the lug on the lock nut).
So bottom line, if you are going to use a myers type hub in a metallic service raceway it has to be the type with the lug and use a bonding jumper. I my neck of then woods, many seem to think a standard hub without the lug (and jumper) is in compliance with 250.92, but after researching this, this is clearly not the case
 
augie47 said:
texie post this a few years back and it is still the case as I understand it:

hubs are covered under DWTT and are suitable for normal grounding. It does not mention use for compliance with 250.92, however if you look at "related products" in DWTT it refers you to KDER which specifically states that KDER covers compliance to 250.92 for grounding and bonding hubs (which are the hubs with the lug on the lock nut).
So bottom line, if you are going to use a myers type hub in a metallic service raceway it has to be the type with the lug and use a bonding jumper. I my neck of then woods, many seem to think a standard hub without the lug (and jumper) is in compliance with 250.92, but after researching this, this is clearly not the case
Click to expand...

I'm going to chew on this information for a bit.
 
quantum said:
We have 12 RGS conduits entering/exiting a service disconnect (metallic enclosure) using myers hubs. Is it really necessary to bond these conduits to the ground bar since the enclosure is metallic? We will be doing so regardless, but if I understand correctly, we already have an electrically continuous raceway.
Click to expand...

If you're using the Basic Scru-Tite Myers hubs for example, vendor cutsheet states it provides an 'electrical ground', therefore you wouldn't need to bond (presuming of course the enclosure is metallic). For an enclosure located in a CID2 classified area, the hubs would have to be bonded to the bus bar per Article 501.30(A).
 
Not much to chew :D
If your metallic conduit contains service conductors (no overcurrent protection) the the hub must be UL KDER listed and requires a bond jumper. Other than service conduits, a KDER or DWTT listed hub can be used and bonding is optional.
 
augie47 said:
Not much to chew :D
If your metallic conduit contains service conductors (no overcurrent protection) the the hub must be UL KDER listed and requires a bond jumper. Other than service conduits, a KDER or DWTT listed hub can be used and bonding is optional.
Click to expand...

Funny how this is so widely asked about and violated. This came up again at a recent IAEI meeting with folks from UL and and CMP 5 present. This was not even a "gray" area for them.
 
HELP- 2 SMALL PARTS STOPPED JOB

HELP- 2 SMALL PARTS STOPPED JOB

I started a thread today but have moved here because this one is in progress and I was kinda asked to do so.

I have a customer who's service is ripped down and they need power so time is of the essence.

Do any of you guys who seem to be much smarter than me know what "MYERS HUB" type product is KDER and or UL 467 rated for the service entrance as it has been stated it has to be? Brand? Retailer?

I need 2" and it must connect to #4 CU bonding jumper.

All products I have looked up say they meet 514B standard with UL E14814 listing or I think just DWTT.
One product line I found says it is approved for service entrance on spec sheet but then has the same 514B standard and E14814 listing.

The supply shop (Rexel) has never heard of such a rating. So I have literally spent hours on line trying to read random products that could meet the spec. None found.

I can find many products that have a ground lug on lock nut but Just having this does not seem to meet KDER.

I have called the manufacture of myers hubs and the guy did not know and needs to research and get back to me. This product also limits the wire size in spec sheet to less than I need witch he is also looking into.

Details of my install in this post
http://forums.mikeholt.com/showthread.php?t=191537

Thanks!
 
Last edited:
florida-sparkey said:
I started a thread today but have moved here because this one is in progress and I was kinda asked to do so.

I have a customer who's service is ripped down and they need power so time is of the essence.

Do any of you guys who seem to be much smarter than me know what "MYERS HUB" type product is KDER and or UL 467 rated for the service entrance as it has been stated it has to be? Brand? Retailer?

I need 2" and it must connect to #4 CU bonding jumper.

All products I have looked up say they meet 514B standard with UL E14814 listing or I think just DWTT.
One product line I found says it is approved for service entrance on spec sheet but then has the same 514B standard and E14814 listing.

The supply shop (Rexel) has never heard of such a rating. So I have literally spent hours on line trying to read random products that could meet the spec. None found.

I can find many products that have a ground lug on lock nut but Just having this does not seem to meet KDER.

I have called the manufacture of myers hubs and the guy did not know and needs to research and get back to me. This product also limits the wire size in spec sheet to less than I need witch he is also looking into.

Details of my install in this post
http://forums.mikeholt.com/showthread.php?t=191537

Thanks!
Click to expand...

Found info for others:
Went to UL KDER product spec and worked backwards till I found a local product. UL link below

"Myers" is a listed trade name of Cooper and product is STG 6

http://productspec.ul.com/document.php?id=KDER.E59509
 
As texie pointed out, it is an often overlooked requirement. Kudos on taking the time to find the proper product.
 
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