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- Thread starter kenet
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bphgravity
Senior Member
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Re: 1
Your question is a little vague. The best place to start would be 250.148 of the NEC. Many of these requirements are related to continuity of attachment and dedicated and purposeful use.
One common misconception is that the code requires a green colored grounding screw. This is not the case. The main concern is ensuring that whatever screw is used to terminate or connect an enclosure to the equipment grounding conductors, that it is used for no other purpose. (250.148(A).
Similar to the requirement of green wire connectors, use of a green screw should be reserved for grounding connections, however a green screw is not necessarily required.
Your question is a little vague. The best place to start would be 250.148 of the NEC. Many of these requirements are related to continuity of attachment and dedicated and purposeful use.
One common misconception is that the code requires a green colored grounding screw. This is not the case. The main concern is ensuring that whatever screw is used to terminate or connect an enclosure to the equipment grounding conductors, that it is used for no other purpose. (250.148(A).
Similar to the requirement of green wire connectors, use of a green screw should be reserved for grounding connections, however a green screw is not necessarily required.
Re: 1
250.8 Connection of Grounding and Bonding Equipment.
Grounding conductors and bonding jumpers shall be connected by exothermic welding, listed pressure connectors, listed clamps, or other listed means. Connection devices or fittings that depend solely on solder shall not be used. Sheet metal screws shall not be used to connect grounding conductors to enclosures.
According to 250.8 the bonding screw in the box must be listed. Thus you would have a green screw
[ May 18, 2003, 08:28 PM: Message edited by: gregory ]
250.8 Connection of Grounding and Bonding Equipment.
Grounding conductors and bonding jumpers shall be connected by exothermic welding, listed pressure connectors, listed clamps, or other listed means. Connection devices or fittings that depend solely on solder shall not be used. Sheet metal screws shall not be used to connect grounding conductors to enclosures.
According to 250.8 the bonding screw in the box must be listed. Thus you would have a green screw
[ May 18, 2003, 08:28 PM: Message edited by: gregory ]
Re: 1
250.126 seems to be for DEVICE(s).
Is a screw which is screwed (by an electrician) into the 10/32 threaded hole in the back of an electrical device box or a 1900 box " not readily removable" ?
Apparently if the area near the 10/32 threaded hole has the ground sysmbol, the answer is , yes 250.126(3).
The reason I'm questioning this, is because recently I saw the bus screws in a 3? 4W sub-panelboard which used green and / or blue screws to assemble the phase bus(s) as well as the un-grounded neutral bus(s). I did not note a "ground" sysmbol near-by.
250.126 seems to be for DEVICE(s).
Is a screw which is screwed (by an electrician) into the 10/32 threaded hole in the back of an electrical device box or a 1900 box " not readily removable" ?
Apparently if the area near the 10/32 threaded hole has the ground sysmbol, the answer is , yes 250.126(3).
The reason I'm questioning this, is because recently I saw the bus screws in a 3? 4W sub-panelboard which used green and / or blue screws to assemble the phase bus(s) as well as the un-grounded neutral bus(s). I did not note a "ground" sysmbol near-by.
- Location
- Illinois
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- retired electrician
Re: 1
250.126 only applies to wiring devices. In my opinion 250.148(A) permits any 10-32 screw to be used as long as it serves no other purpose.
Don
250.126 only applies to wiring devices. In my opinion 250.148(A) permits any 10-32 screw to be used as long as it serves no other purpose.
Don
Re: 1
The question was requirments for grounding screws, Art. 250.126 makes that very clear.As for the screw not been readily removable, once the device,or light fixture, etc. is installed the green ground screw is no longer readily removable, due to the fact that you would have to remove the device and plate, or disassemble the fixture to get to the ground screw, as for that green ground screw been used for just grounding purposes, the 10/32 that is for the cable clamps would be a violation of Art. 250.148 (A), just as you would not be permitted to use a 10/32 screw that is been used to support a light fixture,or a screw that is been used to support a box or fixture. As for a listed device, a ground clip would be permitted and as Gregory stated the screw would also have to be listed, in other words meet the requirments of Art. 250.126.
The question was requirments for grounding screws, Art. 250.126 makes that very clear.As for the screw not been readily removable, once the device,or light fixture, etc. is installed the green ground screw is no longer readily removable, due to the fact that you would have to remove the device and plate, or disassemble the fixture to get to the ground screw, as for that green ground screw been used for just grounding purposes, the 10/32 that is for the cable clamps would be a violation of Art. 250.148 (A), just as you would not be permitted to use a 10/32 screw that is been used to support a light fixture,or a screw that is been used to support a box or fixture. As for a listed device, a ground clip would be permitted and as Gregory stated the screw would also have to be listed, in other words meet the requirments of Art. 250.126.
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