Yes, as you described, there is a green insulated wire included in the run. I will need to open things up to see if there is also a bare copper wire for grounding the box and to confirm that the box is metal... but I know we used an armored cable running on the outside of the wall to get this additional dedicated circuit to my amps, and so the armor on the cable acts as further shielding/ground, but is not the same as the green wire (isolated) ground.
ya, that would be a good idea. Saves a lot of guess work what the electrician used.
Don't forget to turn off the breaker. Verify the circuit is dead.
While looking inside the outlet box look for two green insulated ground wires.
Write down the number of, and colors of, all the wires in the armor cable.
Are you sure the duplex outlet(s) are IG grounding type? They are orange in color or have an orange triangle on the face plate? Like this one for example.
Here is an example of a Hubbell IG Hospital Grade duplex receptacle.
I assume your house is wood framing. Why did you go with IG outlets and IG ground. What did the electrician say about it? Or was it his suggestion?
I'm glad you didn't say the IG ground wire connects to a dedicated ground rod. That's usually the cause.
FWIW not that many IG outlets are installed these days. They really are only used in commercial and industrial facilities. They where big in the 1970s, 1980s, and into the 1990s but really dropped off in the 2000s.
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