Internal cable clamps

[macmikeman]

Question: On single gang clip in metal boxes with an angled rear wall there are 2 knockouts and a single gull wing cable clamp. Have I answered my question already? Here is the question- counts as a single clamp or a double clamp? Here is the next question. If that particular type of clamp with spread wings as it were is counted as two clamps since it covers two openings, then what is the count if you only enter one cable into the box? Curious minds seek to know these things.

 

[infinity]

If there is a cable clamp at both the top (2 entry hole) and at the bottom (2 entry holes) it counts as a single conductor.

 

[macmikeman]

Ah yes, Always cable clamps count as one. I had a senior citizen moment there, and you fixed it for me. Thanks. Mrs macmikeman is getting worried about me.

 

[infinity]

I hear you I have those moments too. It's one of the mysteries of the NEC why I can remove and throw away one of the two clamps in the box and get no credit for the extra space in the box. It's things like that that I loathe about the NEC.

 

[hbiss]

It's one of the mysteries of the NEC why I can remove and throw away one of the two clamps in the box and get no credit for the extra space in the box. It's things like that that I loathe about the NEC.

If you are saying that by removing it the cubic inches available doesn't increase, that's correct. But if you leave the clamp in the box and don't use it, it still counts as a clamp when counting clamps. So, in effect removing it does increase capacity.

-Hal

 

[infinity]

If you are saying that by removing it the cubic inches available doesn't increase, that's correct. But if you leave the clamp in the box and don't use it, it still counts as a clamp when counting clamps. So, in effect removing it does increase capacity.

-Hal

Removing one clamp physically increases the space within the box but you still have a 1 conductor deduction for the other clamp. One or two clamps in the box same deduction which makes no sense.

 

[hbiss]

Removing one clamp physically increases the space within the box but you still have a 1 conductor deduction for the other clamp.

Two clamps= two conductors. Remove one clamp and you gain a conductor, no? That's the way I've always done it.

-Hal

 

[infinity]

Two clamps= two conductors. Remove one clamp and you gain a conductor, no? That's the way I've always done it.

-Hal

No, one clamp or two clamps same deduction, one conductor. Doesn't make much sense to me why but that's what is says.

314.16(B)(2) Clamp Fill.
Where one or more internal cable clamps, whether factory or field supplied, are present in the box, a single volume allowance in accordance with Table 314.16(B) shall be made based on the largest conductor present in the box. No allowance shall be required for a cable connector with its clamping mechanism outside the box.

 

[electrofelon]

Removing one clamp physically increases the space within the box but you still have a 1 conductor deduction for the other clamp. One or two clamps in the box same deduction which makes no sense.

Better yet, maybe just dump the clamp deduction all together?

 

[infinity]

Better yet, maybe just dump the clamp deduction all together?

Box fill has always been a pet peeve of mine because the inconstancies like this one. For example if I put a metal barrier in a box that's 1/16" of an inch thick that has to count towards box fill. Silly...

 

[electrofelon]

Box fill has always been a pet peeve of mine because the inconstancies like this one. For example if I put a metal barrier in a box that's 1/16" of an inch thick that has to count towards box fill. Silly...

Yeah me too, and you've got huge variations in the way the box is made up, size of wire nuts used, the size of the device, and those don't count for anything....

 

[Dennis Alwon]

Box fill has always been a pet peeve of mine because the inconstancies like this one. For example if I put a metal barrier in a box that's 1/16" of an inch thick that has to count towards box fill. Silly...

What about the 2020 change for the equipment grounding conductor

(5) Equipment Grounding Conductor Fill.
Where up to four equipment grounding conductors or equipment bonding jumpers enter a box, a single volume allowance in accordance with Table 314.16(B) shall be made based on the largest equipment grounding conductor or equipment bonding jumper entering the box. A 1⁄4 volume allowance shall be made for each additional equipment grounding conductor or equipment bonding jumper that enters the box, based on the largest equipment grounding conductor or equipment bonding conductor.

 

[ActionDave]

What about the 2020 change for the equipment grounding conductor

Further evidence that they don't have enough to do at the conference and we should move to a five year cycle.

 

[infinity]

What about the 2020 change for the equipment grounding conductor

Further evidence that they don't have enough to do at the conference and we should move to a five year cycle.

I couldn't agree more. What happened to "if it ain't broke don't fix it"? This ridiculous splitting hairs approach of rewriting code is just plain dumb.

And why address something that isn't a problem in the first place? I'm wondering when will these CMP's will actually go back to code changes where there is legitimate substantiation. I'll bet that 72 million people died because prior code cycles didn't count 1/4 of a conductor for an EGC. Where's the head slap emoji?

I'm too lazy to look up the new EGC and barrier substantiations because these CMP guys really bore me with their nonsense.

 

[electrofelon]

What about the 2020 change for the equipment grounding conductor

Oh God .....how about just ONE measly code cycle where they JUST fix the myriad of horribly worded and ambiguous stuff.....they would probably just screw that up and make it worse, maybe like Dave said tell everyone to take a vaca and find something else to hand wring about...