brass mounting screw on receptacle

hi

i'm extending a 20 amp circuit. the 20 amp receptacles i bought have a brass mounting screw on one of the ears. also the ear has a brass covering over it.

what is the purpose of this?

thanks in advance.

 

I take it these aren't the 39 cent receptacles? Some of the higher quality receptacles I've seen have a retention clip for the mounting screw on one of the ears. I assume this is to maintain better contact for the self-grounding feature. Of course this would only apply if the device were mounted in a metal box.

 

In some jurisdictions, and in the opinions of the governing body of the code commitee, that screw and retainer can be used on metal boxes as the ground path!

I have mentioned this before, the NEC code is only a guide, Municipalities may or may not at thier discretion pass laws making it the official code for that area!! Very often larger municipalities revise the code before making it LAW. NYC, State of Mass and varoius other araes use it with Revisions written into the law.

 

Hotarc and imjerry: since you mentioned the ground path in your post, I might as well ask my next question here.

I’m installed twin receptacles in one metal box. Both receptacles have the ground strap connecting both mounting ears and ground screw. Both have the brass screw and retention clip.

Instead of a ground wire from each receptacle, is it acceptable to connect a ground to only one receptacle? I figure the 2nd outlet is grounded by the metal box which is grounded by the 1st receptacle. Also my test lamp indicates the outlets and box are properly grounded.

This saves a very small bit of work but it makes the job a bit neater.

Thanks again

 

If you use a self-grounding receptacle, it may not be necessary to run a wire to the receptacle screw if you run a grounding wire to the box (which is required). But I would anyway. The improved grounding connection is worth the extra sixty seconds.