Is this device grounded?

Learn the NEC with Mike Holt now!

Is this device grounded?

  • Total voters
    97
Status
Not open for further replies.
e57 said:
How does this install situation fit the condition in 404.9(B)1?????


IMPO this portion of the code should be more clear - but here we are.... :roll:
Click to expand...
It fits 'cause the passage doesn't say "tight", or something like that, to describe the state of the screws.
 
Probably a stupid question---> I only use P&SL devices so I don't know about other brands but isn't this part of the reason they switched to the little wire screw retaining clips as opposed to the little piece of oil board?
 
al hildenbrand said:
Here's the Code
Click to expand...
2008 NEC

404.9 Provisions for General-Use Snap Switches.

(B) Grounding. Snap switches, including dimmer and similar control switches, shall be connected to an equipment grounding conductor and shall provide a means to connect metal faceplates to the equipment grounding conductor, whether or not a metal faceplate is installed. Snap switches shall be considered to be part of an effective ground-fault current path if either of the following conditions is met:
(1) The switch is mounted with metal screws to a metal box or metal cover that is connected to an equipment grounding conductor or to a nonmetallic box with integral means for connecting to an equipment grounding conductor.
Click to expand...
If this were a surface mounted box with even semi-snug connections I would say it fits the code. In this case the switch can not be considered "Mounted" to anything, and if the screws were tight it would be "mounted' to the sheetrock - not the box....
 
sii said:
Probably a stupid question---> I only use P&SL devices so I don't know about other brands but isn't this part of the reason they switched to the little wire screw retaining clips as opposed to the little piece of oil board?
Click to expand...
That is a self-grounding device.... ;)
 
iwire said:
There is nothing permanent about a intermittent path.

Would you view a foot lug connected loosely to an enclosure as meeting 250.4(A)(5)
Click to expand...
Well, the lug doesn't have the equivalent of the mounting instructions implied in 404.9(B)(1).

One way the language of 404.9(B)(1) could be improved would be by saying something like "firmly mounted" in the condition of (1).

But as is, 404.9(B)(1) doesn't exclude loose mounting, IMHO.
 
e57 said:
If this were a surface mounted box with even semi-snug connections I would say it fits the code. In this case the switch can not be considered "Mounted" to anything, and if the screws were tight it would be "mounted' to the sheetrock - not the box....
Click to expand...
Mounting, IMO, is not exclusively "mounting directly to the box". I just don't see that in the language.
 
iwire said:
There is nothing permanent about a intermittent path.
Click to expand...
Now, if the Poll Question was: "As illustrated, is there electrical continutiy that is reliable between the dimmer yoke and the box?" I would answer no.
 
al hildenbrand said:
One way the language of 404.9(B)(1) could be improved would be by saying something like "firmly mounted" in the condition of (1).

But as is, 404.9(B)(1) doesn't exclude loose mounting, IMHO.
Click to expand...
I agree - but 250.4(A)5 does...

al hildenbrand said:
Mounting, IMO, is not exclusively "mounting directly to the box". I just don't see that in the language.
Click to expand...
In the case of flush mounted boxes - in most cases a mud ring only acts as a toggle for mounting to the gypsum surface... It is and could not be mounted to the box at all - unless the ring were proud of the rock surface. If the yoke could touch the box - I would say it were "mounted" "to the metal box" it "with metal screws" and meet the condition in 404.(B)1 - otherwise it needs an EGC - IMO.

al hildenbrand said:
Now, if the Poll Question was: "As illustrated, is there electrical continutiy that is reliable between the dimmer yoke and the box?" I would answer no.
Click to expand...
The question was is this device grounded? "Grounded" has a definition in 100, and in this case is a connection between the device yoke and the box - not the screws used to do so.
 
jumper said:
Not that my opinion counts, but that is the answer I have been looking for as I have read the posts on this thread. Thank you sir.
Click to expand...
Oh you count.... Just as much as the rest of us. But the question was what it was - is it grounded or not? Only two answers: yes or no? No tricks or qualifiers...
 
e57 said:
Oh you count.... Just as much as the rest of us. But the question was what it was - is it grounded or not? Only two answers: yes or no? No tricks or qualifiers...
Click to expand...

Okay, then yes it it is grounded per 404.9(B)(1). As stated it says metal screws and that is what is shown. I do not like it, but it says what it says. Nothing about tight or in contact. Implied: yes, Stated :no.
 
al hildenbrand said:
One way the language of 404.9(B)(1) could be improved would be by saying something like "firmly mounted" in the condition of (1).

But as is, 404.9(B)(1) doesn't exclude loose mounting, IMHO.
Click to expand...

I think it is generally expected that an electrical connection not be loose and that we are not always specifically told a connection must be tight.
 
iwire said:
I think it is generally expected that an electrical connection not be loose and that we are not always specifically told a connection must be tight.
Click to expand...
I submit that the real issue with the OP diagram is that the mounting is loose. As such it doesn't meet the requirements in 110.13(A). Devices are Equipment.

When this dimmer is firmly against the wall, then the screws are making a connection tight enough, evidently, as that's what 404.9(B)(1) and 404.9(B) seem to say.
 
My two zincs...

e57 said:
I agree - but 250.4(A)5 does...
Click to expand...

As does 404.10(B).

404.9(B)(1) does not say the yoke has to make physical contact with the metal box or grounded box ring. The switch in the picture is mounted to a grounded metal cover with metal screws, thus it satisfies that section.

Loose screws do not make for an effective ground path, so I say the switch is not grounded.
 
jumper said:
Okay, then yes it it is grounded per404.9(B)(1). As stated it says metal screws and that is what is shown. I do not like it, but it says what it says. Nothing about tight or in contact. Implied: yes, Stated :no.
Click to expand...
It says mounted to a metal box - it isn't... If it were tight - it would be mounted to the gyp board... ;) If we want to get technical - it is at minimum mounted to the ring - not the "box". (And it is not mounted to a cover either...)
 
e57 said:
It says mounted to a metal box - it isn't... If it were tight - it would be mounted to the gyp board... ;) If we want to get technical - it is at minimum mounted to the ring - not the "box". (And it is not mounted to a cover either...)
Click to expand...
May I suggest replacing the box / plaster ring with a simple single gang wall case? That side steps this and keeps the focus on your initial question.
 
al hildenbrand said:
May I suggest replacing the box / plaster ring with a simple single gang wall case? That side steps this and keeps the focus on your initial question.
Click to expand...

Alright - It is exactly the same... Still not mounted to the box... And... Not grounded!

attachment.php
 
Status
Not open for further replies.
Top