Aluminum ground in flex conduit

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Old 02-22-15, 10:42 AM
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Aluminum ground in flex conduit

In my process of tracing the household wiring to have a more accurate description of each breaker on our newly upgraded panel, I came upon a junction box that had 4 cables tied into it:
  • 12 awg, flex conduit to a kitchen 20 amp GFCI
  • 12 awg, outdoor romex to an outlet in sunroom and an exterior outlet
  • 14 awg, outdoor romex to a sunroom outlet
  • 14 awg, outdoor romex feed to 15 amp breaker in panel

Knowing 12 and 14 shouldn't be on the same run, I separated all the wires. I added a new 15 amp outlet to connect the two 14 AWG's in. But I'm not sure how to wire the 12's.

I have a 20 amp outlet in a nearby utility room on it's own breaker that I would like to tap the other two 12 AWG's to, but I'm not comfortable with the flex wiring. The flex has a black, white, and a very short aluminum wire that was curled up and was not connected to anything in the junction box. Something tells me joining an aluminum and copper ground is not a safe thing to do. Replacing the flex with Romex is not an option without ripping out some walls to re-run it. Any ideas on what to do from the pro's here?
 
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Old 02-22-15, 11:25 AM
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Can you post a picture? .
 
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Old 02-22-15, 11:56 AM
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Spiral metal flex conduit may have an aluminum strip or a bare wire running the full length inside, outside any paper lining in the conduit. This together with metal outlet boxes and proper box to conduit clamps is needed to qualify the conduit as being the equipment grounding conductor for that portion of the branch circuit. This strip or bare wire does not need to come into the box and be wire nutted to other equipment grounding conductors.
 
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Old 02-23-15, 08:31 AM
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I've tried uploading a .jpg pic from my computer and photo bucket. Both get an error failed message. Don't know why, I've done it before.
 
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Old 02-23-15, 09:07 AM
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Ah...had to make the pic smaller.

If I'm understanding ALLANJ correctly. This flex cabling needs to be properly connected/clamped in the metal J-box and by that it's qualified as grounded? From that point, I'm ok to join the 2 wires from the flex to the feed romex and a 12 AWG romex running to 2 outlets?
 
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Old 02-23-15, 09:18 AM
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That small Al conductor shown is the bond strip. It can be cut flush or wrapped into the spirals. Use a proper connector and a redhead bushing.
 
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Old 02-23-15, 09:34 AM
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The grounds for your new NM runs will be connected together with a pigtail and the pigtail secured to box using a ground screw.

The box is grounded to panel using the BX Steel jacket, properly clamped to metal box.
After securing BX to box, check for a good ground by measuring hot wire to box. It should be ~120V
 
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Old 02-23-15, 09:52 AM
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That's what I needed to know. Thanks Handyone!
 
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