"Mikepier" wrote in message
...
On Apr 1, 6:31 pm, "RBM" wrote:
"Mikepier" wrote in message

...

** MC cable has an additional copper ground conductor-

Yes, that is known as MC lite with the aluminum clad . But the old BX
relied on the steel clad for a ground.

** and the new BX (AC) lite relies on it's aluminum shield for it's
ground.

Then why do they put a seperate green ground conductor in the aluminum
MC cable where conventional BX did not have a seperate ground?
These days if you go to Lowes or HD, all they have is MC Lite 12/2
with a ground. I think HD still has the "classic" 12/2 steel BX on
the shelf with no seperate ground.

They are simply two different types of cables, which are used for different
purposes. For example: In places of public assembly, you can use MC cable ,
but AC cable is not allowed.
Aluminum sheathed AC cable has been on the market since 1959, the same year
that the Nec required AC cable to have the bond conductor