Should I connect green and bare grounds?

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  #1  
Old 05-08-12, 11:16 AM
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Should I connect green and bare grounds?

In replacing some old outlets in my house, it looks like they used 14/3 wire and ive verified that black is line, white is neutral, green is ground, bare is ground with a multitester.

The green is connected to the outlets ground terminal, but the bare is just pushed back in the outlet box not connected to anything. It works fine but i'd like to know the correct code compliant way to do it. Im in NH in the US.

Should the green and bare wires be connected then run a pigtail to the outlet ground terminal? Should I run a ground to the metal box as well?

Thanks!
 
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Old 05-08-12, 11:19 AM
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14-3 cable SHOULD have black, white and red insulated conductors along with a bare equipment grounding conductor. Are you certain you have black, white and green?
 
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Old 05-08-12, 11:28 AM
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As Furd said, it is unusual to have both a green and a bare in the wiring.
 
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Old 05-08-12, 11:32 AM
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Can you post a picture with the receptacle pulled out? http://www.doityourself.com/forum/li...-pictures.html
 
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Old 05-08-12, 11:48 AM
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Yes, green and bare wires should all be connected (tied; bonded) together.

In the U.S. green wires may not be used for anything besides grounding.

I have never heard of a cable that has both green and bare conductors inside.

Romex rarely has green insulated equipment grounding conductors but many types of appliance cords do have black, white, and green.

Persons with some kinds of color blindness may confuse the red conductor of 3 wire cable for a green equpment grounding conductor.
 
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Old 05-08-12, 11:54 AM
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In replacing some old outlets in my house, it looks like they used 14/3 wire and ive verified that black is line, white is neutral, green is ground, bare is ground with a multitester.
That doesn't sound like 14/3 cable. That sounds like 14/2 with a "clean" (isolated) ground and a "dirty" (non-isolated) ground. I've only encountered that in health care facilities, and there the two grounds were both insulated. One had a yellow stripe in the green.

Yes, a picture would help.
 
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Old 05-08-12, 05:20 PM
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That doesn't sound like 14/3 cable. That sounds like 14/2 with a "clean" (isolated) ground and a "dirty" (non-isolated) ground. I've only encountered that in health care facilities, and there the two grounds were both insulated. One had a yellow stripe in the green
The OP stated cable, but didn't specify if the cable was NM, MC or even SO cord (or SJ cord) nor was it stated how many cables were in each box. Hospital Grade MC cable typically would have a green grounding conductor and a bare redundant ground.
 
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Old 05-08-12, 07:43 PM
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Hospital Grade MC cable typically would have a green grounding conductor and a bare redundant ground.
FWIW, the HCF MC cable I've worked with was 1) real MC, not MC Lite, and 2) had, for a 2-conductor cable, 1 hot, 1 neutral, 1 green-insulated dirty ground and 1 green-with-yellow-stripe-insulated clean ground. YMMV.
 
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Old 05-09-12, 04:55 PM
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This is what I was referring to as Hospital Grade. There are many different types which could be discussed in another thread.

http://www.afcweb.com/pdf_2011/p12_mc_s_lt.pdf

My point was that if the OP encountered both an insulated green ground and a bare ground, it could have been Hospital Grade (or HCF Grade) MC cable.

Was the bare ground conductor copper or aluminum?
 

Last edited by CasualJoe; 05-09-12 at 05:01 PM. Reason: spelling
  #10  
Old 05-10-12, 12:49 PM
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Ive gotten to the bottom of this issue. There is just black, white and green wires coming out of the cable.

The bare thats in there was a lose piece of wire that had 1 end wrapped behind the large screw on the rommex connector so it looked like it was coming out with the rest of the wires. Im guessing at one point it was used to ground the outlet to the box., Ive seen grounds going to a screw on the metal box, and a clip, but id personally never seen one wrapped around the connector.

Thanks for everyones help!
 
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Old 05-10-12, 12:52 PM
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But if you have Romex it will either have no ground or a bare ground. I will not have a green ground. Are you sure it isn't MC cable?
 
  #12  
Old 05-10-12, 08:25 PM
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If it's a metal box, it must be bonded to ground. This can be done either by supplying it with MC cable, which sounds like what you have, or by connecting the ground wire to the box with a green, hex-head 1032 machine screw.
 
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