Grounding clip vs. ground screw.

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Fredkehoe

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I am doing a small renovation job in which there is existing two conductor BX cable in the house with no ground except the BX cable. The building inspector wants the box grounded with the wire to the new outlets. Are those green grounding clips that clip on the edge of the box OK? Or does the boxes have to be drilled and tapped and a ground wire screwed in?

I appreciate your help.
 
Fredkehoe said:
I am doing a small renovation job in which there is existing two conductor BX cable in the house with no ground except the BX cable. The building inspector wants the box grounded with the wire to the new outlets. Are those green grounding clips that clip on the edge of the box OK? Or does the boxes have to be drilled and tapped and a ground wire screwed in?

I appreciate your help.
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the clips are UL listed for that purpose.
 
Either method will work but I would just use a self-grounding receptacle and forget the bonding jumper.
 
It's somewhat debatable as to BX is an ECG , as it was not manufactured to be one in the first place

I'd just go with 406.4D, park a DF in the panel ,and use any old crappy receptacle outlet....

~RJ~
 
In NYC even if you use self grounding receptacles you need install a ground tail to the box via a threaded screw, most supply houses around here stock 1900 boxes (4x4) steel boxes with the ground screw already installed some even with the wire to

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nickelec said:
In NYC even if you use self grounding receptacles you need install a ground tail to the box via a threaded screw, most supply houses around here stock 1900 boxes (4x4) steel boxes with the ground screw already installed some even with the wire to

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I believe that you're incorrect can you show me that code requirment?
 
nickelec said:
In NYC even if you use self grounding receptacles you need install a ground tail to the box via a threaded screw, most supply houses around here stock 1900 boxes (4x4) steel boxes with the ground screw already installed some even with the wire to

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That's what can give you extra 'points' to pass inspection. Not a code requirement.
Devil in the detail is that if the box or mud ring is recessed more than 1/4" self grounding clip is not (as much) effective but grounding pigtail is. Grounding path is even worse when you replace the 6/32 screw with a longer one and install switch box extender (goof ring, add a depth adapter, collar).
Self grounding receptacles on powder coated surface 'mulberry' covers require grounding pigtail.
So it is just easier to install a grounding pigtail every time and tell everybody to do so around here.
 
darekelec said:
Self grounding receptacles on powder coated surface 'mulberry' covers require grounding pigtail.
So it is just easier to install a grounding pigtail every time and tell everybody to do so around here.
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That's only on 4 11/16" box mulberry covers, 1900 (4") mulberry covers do not require a bonding jumper.
 
romex jockey said:
It's somewhat debatable as to BX is an ECG , as it was not manufactured to be one in the first place

I'd just go with 406.4D, park a DF in the panel ,and use any old crappy receptacle outlet....

~RJ~
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I agree, there is no way I would rely on an old BX cable armor as an EGC, you might as well strap heating elements to inside of the wall should a fault occur.
 
peter d said:
I agree, there is no way I would rely on an old BX cable armor as an EGC, you might as well strap heating elements to inside of the wall should a fault occur.
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How do you know how old the cable is? The bonding strip was added to AC cable in the mid-1950's and has been there ever since, would that be unsafe as an EGC?
 
infinity said:
How do you know how old the cable is? The bonding strip was added to AC cable in the mid-1950's and has been there ever since, would that be unsafe as an EGC?
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No, I'm talking about the old stuff that has no bonding strip, has rubber and cloth insulated conductors and is usually badly corroded when I encounter it. That makes up the majority of what is installed here in homes, very few have the bonded AC cable.
 
That there was a history of pre EGC wiring methods that evolved to 'bonding strip' BX during the 'two banger' dup rec outlet era ,along with the infamous boston backwrap is indicative of it's viability.

Regardless of the OP's AHJ views on an EGC and/or the provisions of 406.4 to mitigate 'replacement' , one is still dealing with the afci aspect of 406.4




~RJ~
 
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peter d said:
No, I'm talking about the old stuff that has no bonding strip, has rubber and cloth insulated conductors and is usually badly corroded when I encounter it. That makes up the majority of what is installed here in homes, very few have the bonded AC cable.
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I know that BX is a very generic term and has different regional means. Around here some even call modern MC cable BX.
 
darekelec said:
Inspectors here enforce 250.12 on factory painted surface covers
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Then they're enforcing a rule that is not supported by the NEC. 1900/4" Mulberry covers are not required to have a bonding jumper when installed according to 250.146(A). The fact that they're factory painted is irrelevant as they have been tested and listed to bond the receptacle with the factory paint.
 
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