Grounding

I was putting up some new lights at my house. The first couple were wired so that the bare metal ground on the light and in the house wiring were connected together using a wire nut. There were also a couple where these two wires were connected to a screw on the mounting bracket. I went ahead and just wirenutted the two together as above. Now I get to thinking any particularly important reason I shouldn't do that and use the screw on the mounting instead?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Were these metal boxes? If so, I believe the ground should be attached to the box but don't quote me on that. Hopefully an Electrician will come along soon! I have always tied the wire to the box with a grounding screw, unless the box is plastic, then I just wire them together about 15 times and cap it off with a wire nut. Cheers, cc
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
James "Cubby" Culbertson wrote:

If its a metal box or metal fixture you want the ground wire connected to the box or fixture also...this way you wont get the crap knocked out of you if a hot wire comes into contact with the box or fixture.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I do it this way: I leave the ground long, wrap the _incoming_ power feed ground a turn around _one_ box screw (wire is direct from the cable entrance/box clamp to the screw and hard against the back of the box), use the loose end to wirenut to any "outgoing" grounds (cables to other boxes, fixtures mounted on the box etc), and push all of the grounds against the back of the box before doing any more wiring. Takes up virtually zero room.
Some inspectors (and Knight for example), consider using the box _itself_ as a grounding conductor is a sign of poor workmanship - eg: implying that you only use _one_ screw per box, and all grounding circuitry is copper-to-copper connections. Further, Knight wants all boxes in a gang grounded, not using the box-to-box clips as the conductor.
With gang boxes, I leave the feed ground _very_ long. It goes in a line from one screw in each box to the next, with a loop around each. The free end is then used to wire nut to all other grounds. That, plus the way I do hots, mean that the boxes containing gangs of switches look virtually empty - eg: only two wirenuts.
This is more or less what you do for your first inspection - layout and connect all the grounds, leaving a loose end of the ground exposed where you're going to install box devices (outlets, fixtures).
Thus, your first inspection permits the inspector to see your grounding workmanship without the rest of the stuff in the way.
Once you pass your first inspection, except for loose ends in boxes where you now have to install outlets/devices, you don't have to touch the grounds again.
--
Chris Lewis, Una confibula non set est
It\'s not just anyone who gets a Starship Cruiser class named after them.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.