# does every metal box need to be grounded?



## jlmran (Feb 8, 2010)

I don't believe it is a requirement that the screw be green.


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## Bluehawks (Jan 13, 2012)

Yes and yes, it shall be a green screw


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## jlmran (Feb 8, 2010)

Green screw citation?


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## stickboy1375 (Apr 28, 2012)

Bluehawks said:


> Yes and yes, it shall be a green screw


It doesn't have to be green... :no:


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## stickboy1375 (Apr 28, 2012)

amakarevic said:


> I was wondering if every metal receptacle need to be grounded via a green ground screw screwed in a hole in the back and connected to the other ground wires coming into and out of the box, in addition to the ground terminal of the possible power outlet or light for which the box is used. Also, if the box is used only as a JB, does it still need to be grounded?
> 
> Thanks


Every metal box needs to be bonded to the grounding conductor...


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## jlmran (Feb 8, 2010)

stickboy1375 said:


> Every metal box needs to be bonded to the grounding conductor...


Yet, I believe it is possible for the box to BE the grounding conductor (e.g. Conduit?)


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## stickboy1375 (Apr 28, 2012)

jlmran said:


> Yet, I believe it is possible for the box to BE the grounding conductor (e.g. Conduit?)


The conduit would be the EGC.... and the box would be bonded by that wiring method.


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## jlmran (Feb 8, 2010)

stickboy1375 said:


> The conduit would be the EGC.... and the box would be bonded by that wiring method.


But couldn't the box act as (a part of) the EGC in the middle of a conduit run? Otherwise, what bonds one pipe to the other?


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## darren (Nov 25, 2005)

stickboy1375 said:


> It doesn't have to be green... :no:


But how will the electrons know that it is a ground screw and not a regular screw.:thumbup:


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## bbo (Feb 28, 2010)

darren said:


> But how will the electrons know that it is a ground screw and not a regular screw.:thumbup:


well if there is one electron missing, you can be positive its a ground screw :laughing:


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## parman (Aug 9, 2012)

amakarevic said:


> I was wondering if every metal receptacle need to be grounded via a green ground screw screwed in a hole in the back and connected to the other ground wires coming into and out of the box, in addition to the ground terminal of the possible power outlet or light for which the box is used. Also, if the box is used only as a JB, does it still need to be grounded?
> 
> Thanks


Your title asks one question and your post asks another.

Does every metal box need to be grounded.....I would say yes. We could argue about special circumstances, but the rule is yes.

Your post asks if every metal receptacle needs to be grounded...I would say yes. A receptacle is not a box. Do you have to use the the green ground screw in the back of a metal box to ground a receptacle? Not necessarily. Some receptacles are self grounding. You could use a self grounding receptacle and attach it to a grounded box and would be fine.

Does a metal box containing wires that is just used as a junction box need to be grounded...Yes. I would use the equipment grounding conductor you pulled with the circuit and bond that to the back of the box via the pre-drilled and tapped hole that is provided.

Now, if you use metal conduit and properly connect your fittings to your metal boxes, then you would not have to use a green ground wire with your circuit. Your conduit would be your equipment ground and would take the place of the green ground wire. But you still would have to connect any grounding means from a light fixture, receptacle, etc to the back of the metal box via the pre-drilled and tapped hole that is provided.

Lets make this real simple. ALL METAL boxes, conduit, etc used in an electrical system needs to be grounded. How you ground them is where it gets interesting.


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## Bluehawks (Jan 13, 2012)

stickboy1375 said:


> It doesn't have to be green... :no:


It says in 250.126 that the terminal for the connection of the equipment grounding conductor shall be identified by one of the following:
1) A green, not readily removable terminal screw with a hexagonal head.
2) green, hexagonal, not readily removable terminal nut.
3) A green pressure wire connector. If the terminal for the grounding conductor is not visible, the conductor entrance hole shall be marked with the word Green or ground, the letters G or GR, a grounding symbol, or otherwise identified by a distinctive green color. If the terminal for the equipment grounding conductor is readily removable, the area adjacent to the terminal shall be similarly marked.


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## Missouri Bound (Apr 9, 2011)

bbo said:


> well if there is one electron missing, you can be positive its a ground screw :laughing:


 
I'll add to the jocularity....if it's a ground screw it can't be *positive*:laughing:


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## Bluehawks (Jan 13, 2012)

parman said:


> Your title asks one question and your post asks another.
> 
> Do you have to use the the green ground screw in the back of a metal box to ground a receptacle? Not necessarily. Some receptacles are self grounding. You could use a self grounding receptacle and attach it to a grounded box and would be fine.


250.146 says that an equipment bonding jumper shall be used to connect the grounding terminal of a grounding type receptacle to a grounded box unless, it is a surface mounted box where you have direct metal to metal contact between the device yoke and the box.


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## stickboy1375 (Apr 28, 2012)

Bluehawks said:


> It says in 250.126 that the terminal for the connection of the equipment grounding conductor shall be identified by one of the following:
> 1) A green, not readily removable terminal screw with a hexagonal head.
> 2) green, hexagonal, not readily removable terminal nut.
> 3) A green pressure wire connector. If the terminal for the grounding conductor is not visible, the conductor entrance hole shall be marked with the word Green or ground, the letters G or GR, a grounding symbol, or otherwise identified by a distinctive green color. If the terminal for the equipment grounding conductor is readily removable, the area adjacent to the terminal shall be similarly marked.


250.126 is for device terminals... not boxes... i.e, a receptacle, switch... etc...


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## stickboy1375 (Apr 28, 2012)

parman said:


> ALL METAL boxes, conduit, etc used in an electrical system needs to be *grounded.* How you ground them is where it gets interesting.


I dislike this terminology, and hopefully it gets addressed in the future, what we are doing is BONDING... and should be treated as such.


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## parman (Aug 9, 2012)

stickboy1375 said:


> I dislike this terminology, and hopefully it gets addressed in the future, what we are doing is BONDING... and should be treated as such.



All metal boxes are to be GROUNDED. You do that by BONDING the equipment GROUNDING conductor to the box.


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## stickboy1375 (Apr 28, 2012)

parman said:


> All metal boxes are to be GROUNDED. You do that by BONDING the equipment GROUNDING conductor to the box.


Dude, you are bonding the boxes... that is the correct terminology...


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## parman (Aug 9, 2012)

stickboy1375 said:


> Dude, you are bonding the boxes... that is the correct terminology...


Don't want to get into a P***ing contest.

You ground your box by bonding it.

Grounding is the act of connecting something to the equipment ground system.

The physical act of connecting something to the equipment ground system is bonding.


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## stickboy1375 (Apr 28, 2012)

parman said:


> Don't want to get into a P***ing contest.
> 
> You ground your box by bonding it.
> 
> ...


Me neither... but bonding is what clears faults... not grounding. :whistling2:


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## parman (Aug 9, 2012)

stickboy1375 said:


> Me neither... but bonding is what clears faults... not grounding. :whistling2:


Do we need to start our own thread?

You cannot clear a fault unless you are grounded. You can bond all you like, but if the system is not grounded.....No fault clears.

Like I said previous. You ground your equipment by bonding it. These are two very distinct words with two very distinct meanings.

I am kind of agreeing with you. You seemed like you wanted to split hairs and that is what I am doing. I am splitting hairs with grounding and bonding terminology and I stand my original statement as being correct.

Do you agree with the terminology in my last post along with my description? If not can you explain, like I did in my last post, the difference besides just repeating "bonding, bonding, bonding".

I am more that willing to accept I am wrong if you can provide me with what the difference is?


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## darren (Nov 25, 2005)

I have to agree with stickyboy. You are bonding the box to the grounding conductor in the panel.


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## jlmran (Feb 8, 2010)

Grounding does nothing to clear faults. Noun vs verb thanks to NEC.


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## stickboy1375 (Apr 28, 2012)

parman said:


> Do we need to start our own thread?
> 
> You cannot clear a fault unless you are grounded. You can bond all you like, but if the system is not grounded.....No fault clears.
> 
> ...


Sure, start a thread, but I can tell you right now, you are using the definitions
incorrectly.  just as the NEC leads you to.


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## stickboy1375 (Apr 28, 2012)

darren said:


> I have to agree with stickyboy. You are bonding the box to the grounding conductor in the panel.


should be ground(ed) conductor....


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## stickboy1375 (Apr 28, 2012)

Here is the easiest way to show that your terminology is wrong, replace the word grounding with earth, and show me how that will clear a fault... Now, we bond everything to the ground(ed) (neutral) conductor to clear faults, not to the earth... the NEC needs to replace the wording of grounding with earth, and more people will understand the confusion.


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## jbfan (Jul 1, 2004)

Grounded, bonded, to the layman they are the same thing, but many electricians do not know the difference either.

The green wires you buy that comes with the screw is called a bond jumper, at least in my neck of the woods.


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## jlmran (Feb 8, 2010)

jbfan said:


> Grounded, bonded, to the layman they are the same thing, but many electricians do not know the difference either.
> 
> The green wires you buy that comes with the screw is called a bond jumper, at least in my neck of the woods.


Bond...James Bond.


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## parman (Aug 9, 2012)

"I have to agree with stickyboy. You are bonding the box to the grounding conductor in the panel."

I agree with this statement, except to say bonding the box to the equipment grounding conductor.



stickboy1375 said:


> should be ground(ed) conductor....


I don't agree with this statement. The grounded conductor would be the "neutral". The "Neutral" or "Grounded conductor" is "White" wire of a 240/120V system. It would be a "Neutral" when it is shared by two Ungrounded conductors.


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## parman (Aug 9, 2012)

jbfan said:


> Grounded, bonded, to the layman they are the same thing, but many electricians do not know the difference either.
> 
> I agree.
> 
> The green wires you buy that comes with the screw is called a bond jumper, at least in my neck of the woods.


That is because it is a bonding jumper.


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## stickboy1375 (Apr 28, 2012)

parman said:


> "I have to agree with stickyboy. You are bonding the box to the grounding conductor in the panel."
> 
> I agree with this statement, except to say bonding the box to the equipment grounding conductor.
> 
> ...


The ground(ed) conductor is what clears the faults.... that's why we BOND to it...


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## parman (Aug 9, 2012)

stickboy1375 said:


> The ground(ed) conductor is what clears the faults.... that's why we BOND to it...


Yes, yes, yes.. Do we actually agree on something?

I find no fault in this statement. But this would be at the source and the original discussion was for a random junction box in the field.


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## jlmran (Feb 8, 2010)

The NEC has created a monster.


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## jlmran (Feb 8, 2010)

parman said:


> Yes, yes, yes.. Do we actually agree on something?
> 
> I find no fault in this statement. But this would be at the source and the original discussion was for a random junction box in the field.


But, the fact that the grounded conductor is grounded has nothing to do with its ability and function to clear faults.


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## ryan50hrl (Jul 14, 2012)

Damn it.....all thats been accomplished here is that I just remembered that I forgot to bond my boxes to the ground in the last two outlets I put in......LOL


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## stickboy1375 (Apr 28, 2012)

parman said:


> Yes, yes, yes.. Do we actually agree on something?
> 
> I find no fault in this statement. But this would be at the source and the original discussion was for a random junction box in the field.


I think we agree, i just take is a step further and realize the NEC has bastardized the word grounding... 

And once they replace the word grounding with earthing, everyone will agree on what is being accomplished.


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## amakarevic (Apr 12, 2007)

what can happen if a metal receptacle is NOT grounded but the outlet or light that it is used for is?


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## parman (Aug 9, 2012)

stickboy1375 said:


> I think we agree, i just take is a step further and realize the NEC has bastardized the word grounding...
> 
> And once they replace the word grounding with earthing, everyone will agree on what is being accomplished.


NEC has gotten better in this regard. You may be right with the replacement of the word grounding with earthing.

I gotta go for the night. I will try and reread my original statement and your comments and rethink what is actually being said. I believe in more ways than is evident, we agree on a lot of what is being discussed.

Your "earthing" comment made me go back and read the NEC definitions and I think I know why we disagree on some things.

And LOOOOOOOOl for this discussion in the DIY forum. Now no one will know what the heck to think:laughing:


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## jlmran (Feb 8, 2010)

amakarevic said:


> what can happen if a metal receptacle is NOT grounded but the outlet or light that it is used for is?


Receptacles receive things. Outlets provide things. Lights are installed at outlets. So are receptacles.

I think what you mean to ask is, what if an outlet box is not bonded, but the device attached to the outlet box is bonded. 

Answer: .....it depends. 

Is the device self bonding?
Is there a fault?
Who is on first?


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## amakarevic (Apr 12, 2007)

jlmran said:


> Receptacles receive things. Outlets provide things. Lights are installed at outlets. So are receptacles.


by "receptacle" i mean just a metal box.
by "outlet" i mean a power outlet, usually a duplex, AKA socket, into which you put the plug from a device or an appliance.
a "light" would be anything that provides illumination and is mounted to a receptacle.
so a receptacle most commonly hosts either an outlet, a light, or is a junction box

sorry for any confusion


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## amakarevic (Apr 12, 2007)

Bluehawks said:


> 250.146 says that an equipment bonding jumper shall be used to connect the grounding terminal of a grounding type receptacle to a grounded box unless, it is a surface mounted box where you have direct metal to metal contact between the device yoke and the box.


what is a "device yoke"?


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## Julius793 (Dec 13, 2011)

amakarevic said:


> what is a "device yoke"?


The metal part on top and bottom of every device where the 6-32 screws go though.


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## electures (Dec 22, 2009)

Bluehawks said:


> Yes and yes, it shall be a green screw


 
Screw does not have to be green.


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## ryan50hrl (Jul 14, 2012)

Julius793 said:


> The metal part on top and bottom of every device where the 6-32 screws go though.


So that meets the requirement? Standard outlets are fine then if I pull the little washer off the 6-32 screw?


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## Jim Port (Sep 21, 2007)

The box cannot be bonded by the 6-32 if the device is grounded. 

A device may be grounded if the box is grounded under certain conditions.


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## brgmgb (Aug 25, 2011)

amakarevic said:


> I was wondering if every metal receptacle need to be grounded via a green ground screw screwed in a hole in the back and connected to the other ground wires coming into and out of the box, in addition to the ground terminal of the possible power outlet or light for which the box is used. Also, if the box is used only as a JB, does it still need to be grounded?
> 
> Thanks


I think all of his questions have been answered, but not in one post. I'll attempt to do that.



> I was wondering if every metal receptacle need to be grounded via a green ground screw screwed in a hole in the back and connected to the other ground wires coming into and out of the box


By receptacle, the OP meant box. It was also established that the ground/bond screw does not have to be green. It also is implied in the answers that it is no good to just put in a screw if you do not connect it back to the grounding conductor coming into the box. The question is, "Does every metal box need to be grounded via a screw in the hole in the back of the box?" For safety, yes. 



> ...in addition to the ground terminal of the possible power outlet or light for which the box is used.


If the "device yoke" is in contact with the metal box, then you probably do not need to run a ground wire to the device's ground screw. But if in doubt, running the extra conductor will not do any harm.



> Also, if the box is used only as a JB, does it still need to be grounded?


I would ground the junction box for the same reason as in question #1. If the bare hot wire comes in contact with the metal box, someone touching the box could receive a nasty shock. In the junction box, you'll wire nut the ground conductors anyway. Just add one more as a jumper/pigtail to the box's ground screw.


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