when running ground into a metal box,is it enough to just pig tail the grounds and attach them to box,or should you also attach a ground to the green screw on the outlet also.....basically what i did was run an additional outlet in my basement,i pigtailed the grounds and attached them to the metal box,and also ran a short green wire fron the outlet screw into the pigtail.i was told there is no need to ground the outlet because the metal box is grounded....

 

You need the ground pigtail to the receptacle grounding screw. While the receptacle may be adequately grounded by the attachment screws, this is an unreliable ground path.

When you're done, check the new receptacle and the other receptacles in this circuit with a $10 circuit analyzer and call your electrical safety authority for an inspection.

 

If you use a special receptacle labeled as "self-grounding", then simply mounting the receptacle to the metal box will ground it. These special receptacles have something more than just the screws to establish the grounding connection. Nevertheless, I still prefer the security of a grounding wire to the green screw.

 

thanks guys for the replies...i have the grounds connected to the box itself and also put a dhort groung fron the pigtail to the outlet ground screw itself,i rather play it safe