George's "Which Is Right" of the Day

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George Stolz

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Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
It's not makeup, assume I am kneeling in front of the box fixing to make it up directly. :)

Edit to add: Sierra, it's not Jeopardy, you don't have to phrase your answer in the form of a question. :D
 

p real

Member
Location
Fort Collins, CO
Picture 2 is a violation. The inner tracer wire on the hcf mc has to be spiralled as it is in pic 1. It is my understanding that the tracer ground is redundant to ensure constant grounding on the cable sheath.
 

p real

Member
Location
Fort Collins, CO
spiralling it is tricky. To get the mc split, antishort bushing installed, tracerwire spiral (going with the ridges on the sheath, and then put into a connector is a bit more time consuming than normal mc. the tracer wire, if properly wound around the cable to allow the connector to fit properly on it, would be visible above the connector. I have seen where guys cut them off inside the connector and it makes for a very poor mechanical connection between the connector andmc.
 

infinity

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Staff member
Location
New Jersey
Occupation
Journeyman Electrician
On MC-ap the aluminum conductor should be cut off as it exits the armor. Nothing more is required. My 2 cents, I hate spiraling especially on AC cable, it's unnecessary and a waste of time. :)
 

Dennis Alwon

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Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I see 3 possible answers

1) the duplex connector is not rated for hospital grade. I will assume the single ones are however I have never seen that style connector.

2) the aluminum strip is twisted on the first pic and is required for hospital grade-- I never worked with hospital grade so this is a bad guess. LOL I know that with reg. mc the strip just gets cut off. I can't imagine why twisting it around the sheath is required for hospital grade

3) The single connectors are not rated as hospital grade
 

wirebender

Senior Member
From Southwire
Field Inspection Guidelines for MCAP cable
Here is a list of details to verify for when inspecting
installations of MCAP and HC MCAP cables.
? Aluminum ground conductor cut flush with armor
? MC Cable Fitting packaging marked MCI-A
 
MC does not need an anti-short bushing.

Picture 1 not supported within 12" from box termination.

spiralling it is tricky. To get the mc split, antishort bushing installed, tracerwire spiral (going with the ridges on the sheath, and then put into a connector is a bit more time consuming than normal mc. the tracer wire, if properly wound around the cable to allow the connector to fit properly on it, would be visible above the connector. I have seen where guys cut them off inside the connector and it makes for a very poor mechanical connection between the connector andmc.
 

Jljohnson

Senior Member
Location
Colorado
I'm going with pic # 2 being the violation, set screw connector and aluminum sheath do not go together. Although, it is hard to tell from the pic if these connectors are actual set screws that contact the sheath or if there is a wedge that the set screw traps against the sheath. The latter would negate my guess :)
 
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