Is this a violation

acin

Senior Member
Location
pacific grove california
Occupation
general building contractor est.1984 . C 10 elec. lic.as of 8 / 7/ 2020
Looks like they tried to hit the studs with the staples. Wonder if there long enough with 5/8 sr?
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
I'll give anyone $20 who can damage that cable with a ladder.

I'm pretty sure we don't have to assume that something like out of a John Wick movie is going to be happening in that garage.
Yup, In my garage the #22 gauge garage door sensor cable is stapled all over the place, along the ceiling and down the wall. To date that has never been damaged either.
 

retirede

Senior Member
Location
Illinois
I'll give anyone $20 who can damage that cable with a ladder.

I'm pretty sure we don't have to assume that something like out of a John Wick movie is going to be happening in that garage.

Also consider the force vectors involved. The force exerted on the NM by the ladder will be a fraction of the person’s weight depending on the angle of the ladder.
And in the example pictured, it would be almost impossible to put a ladder there due to the garage door track in front of it.
 

Knuckle Dragger

Master Electrician Electrical Contractor 01752
Location
Marlborough, Massachusetts USA
Occupation
Electrical Contractor
How about just don't lean the ladder on the live wire.

My entire 18 year old tool shed is wired in NM.
Chain seas, rakes,shovels, crowbars, pikes, bow saws, weed wackers, etc. None of it has been subjected to physical damaged.
But when I wire a customer's shed it's typically in emt and metal flexible conduit.
 

DrSparks

The Everlasting Know-it-all!
Location
Madison, WI, USA
Occupation
Master Electrician and General Contractor
Also consider the force vectors involved. The force exerted on the NM by the ladder will be a fraction of the person’s weight depending on the angle of the ladder.
And in the example pictured, it would be almost impossible to put a ladder there due to the garage door track in front of it.
Compression damage to copper wire is surprisingly easy to accomplish. You may not see the problem until years down the road when the damaged section heats up and fails due to metal fatigue.

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ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min without traffic from wing
Occupation
Licensed Electrician
Compression damage to copper wire is surprisingly easy to accomplish. You may not see the problem until years down the road when the damaged section heats up and fails due to metal fatigue.

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So what are we to do about the coming apocalypse from all the wires stuffed in junction boxes, especially the ones behind a GFI receptacles?
 

DrSparks

The Everlasting Know-it-all!
Location
Madison, WI, USA
Occupation
Master Electrician and General Contractor
So what are we to do about the coming apocalypse from all the wires stuffed in junction boxes, especially the ones behind a GFI receptacles?
Well I wouldn't put it to that extreme. A receptacle outlet is at the end of a circuit. A cable feeding a whole string of outlets potentially sees considerably more load.

Also stuffing an outlet is not the same as striking a cable with a sharp edge.

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jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
Retired Electrical Engineer - Power Systems
Compression damage to copper wire is surprisingly easy to accomplish. You may not see the problem until years down the road when the damaged section heats up and fails due to metal fatigue.
In that case, I hope you don't step on any NM during the installation process.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
Compression damage to copper wire is surprisingly easy to accomplish. You may not see the problem until years down the road when the damaged section heats up and fails due to metal fatigue.

So…
334.30 is setting us up for failure??
:unsure:;)
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
Retired Electrical Engineer - Power Systems
A 20 oz. hammer and a metal staple will do more damage than a leaning ladder.
I agree. It seems most examples given for possible NM damage are really incidental contact or not much more than it sees during installation.
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
I agree. It seems most examples given for possible NM damage are really incidental contact or not much more than it sees during installation.
Most of the rules put in place to protect stupid people from doing dumb things that will hurt themselves or others, this is not limited to electrical installation requirements.
Some changes came about as a better understanding of risks or how things actually work. Look at KT, it worked for years and I've come across some that is still in use, or old romex with undersized ground conductor used for years as well, but as knowledge increased it was seen the safety concerns with them.
Other changes just to protect people from doing dumb stuff, like using the hair dryer in the shower, or the person that wants to continue using a damaged cord
Of course getting rid of all these extra rules could be used for population control and create a smarter society. "If common sense was so common, more people would have it."
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
The varying opinions in this thread show us why the ambiguities in the NEC should be rewritten or removed.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
I can almost guarantee everyone on this forum has witnessed energized NM used as clothes hangers, tool rests, or used as something other than a means of carrying current conductor without any problems.
It’s tough stuff. It’s why it’s used so much.
Personally, I see no problem with the OP.
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
I can almost guarantee everyone on this forum has witnessed energized NM used as clothes hangers, tool rests, or used as something other than a means of carrying current conductor without any problems.
It’s tough stuff. It’s why it’s used so much.
Personally, I see no problem with the OP.
But I've also seen where it had made a dangerous situation, sheathing torn open, conductor pulled from the box, etc. Not everyone has for instance a quality ladder in good condition. I've also seen where a GC in process of setting up a ladder that a sharp edge sliced into an NM sheathing that was exposed similar to above.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
Retired Electrical Engineer - Power Systems
I've also seen where a GC in process of setting up a ladder that a sharp edge sliced into an NM sheathing that was exposed similar to above.
Is a slice in the sheath an unsafe condition? Can't it be repaired with just electrical tape?
I cannot think of more typical potential damage than what can be caused during installation by pulling around sharp corners, being hit with a hammer as described by infinity, or the countless other perils of a construction site.
 

kwired

Electron manager
Location
NE Nebraska
IMO almost everyone goes way overboard with this "subject to physical damage". really guys, what on Earth is going to damage that cable especially at eight feet up? Hang a rake on it, lean a ladder against it I'm sure it's going to be just fine. The nec allows exposed NM, as long as it closely follows the surface, so I hate this interpretation that whenever it's run exposed, then it's subject to physical damage. Why did the code writers allow it be run on the surface then if whenever it's run on the surface its subject to physical damage and thus can't be run exposed..... 😕🙃😶??

All that said, I do consider that pretty hack....

And that is where some these rules come from. Inspector learned earlier on that you should protect it because whoever he learned it from thought that way, which is a fine design decision but still not what code is really saying, so inspector maybe thinks it is the rule without ever reading deep enough to discover otherwise.

It says what it says not what you think it says.

Charlies rule hasn't been mentioned in a while that I am aware of.
 
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