AC cable

Disclaimer: These are my educated guesses:

electrofelon said:
. . . I have always wondered why that thing is so tiny . . .
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Because it only needs to carry current from one wrap of the sheath to the next wrap.

electrofelon said:
. . . so why the dramatically larger strip/conductor in AP?
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Because the strip itself is sized to be an EGC, not merely help the sheath be the EGC.
 
electrofelon said:
Good point, never really thought about it that way. So does MC AP have a wire EGC? I know you don't terminate it but is this considered to be a wire EGC and the connection is made by the connector?
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No it does not have a wire type EGC. The jacket with the solid conductor are the EGC. The aluminum conductor does not get terminated like an EGC it just gets cut off.
 
electrofelon said:
But the question is why the dramatically larger bonding strip in MCAP? Presumably the bonding strip in AC has been tested and shown to be adequate (even though I have always wondered why that thing is so tiny) so why the dramatically larger strip/conductor in AP? Perhaps just a marketing thing to make it seem much better?
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It's been awhile since I've touched any AC, but I recall it being much heavier than MC. Maybe there's just more metal in the AC making it a better conductor with a smaller strip than MC?
 
electrofelon said:
But the question is why the dramatically larger bonding strip in MCAP? Presumably the bonding strip in AC has been tested and shown to be adequate (even though I have always wondered why that thing is so tiny) so why the dramatically larger strip/conductor in AP? Perhaps just a marketing thing to make it seem much better?
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It's larger so that it comes into contact with the ribs in the sheathing. The sheathing and the giant aluminium conductor work together to make the sheathing a legitimate EGC.
 
hbiss said:
No, it doesn't become an inductive coil. Rather, corrosion causes the wraps to lose conductivity with each other making the corroded section of armor a straight strip of steel like before it was wrapped around the conductors forming the armor. So, just for giggles, if you took a length of stripped armor that you threw on the floor and untwisted and straightened it out, what would the resistance be if you measured a linear foot of it? Then figure the amount of current that there would have to be passing through it to heat it so it glows red.

-Hal
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That makes sense.
 
CoolWill said:
Are the conductors still wrapped in paper?
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Yes. Exactly the same.

ActionDave said:
AC doesn't have a straight strip.
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Any of the AC I have ever seen does. The same as MCAP only smaller. Running it straight contacts the underside of the armor corrugations with the shortest length of wire which is held in contact by the wrapping of the armor. So, really, MCAP is no better than AC. Both rely on the integrity of the connectors for the EG bond. Even NM is better in that respect.

The original MC with the green insulated ground was introduced to provide a positive EGC because it does not rely on the connectors or the resistance of the armor. Then, I guess, there were complaints of it taking more time to install, box fill, etc. by the commercial guys who were used to working with AC. So, they invented MCAP to make them happy which, AFAIC, is a step backward.

-Hal
 
hbiss said:
So, they invented MCAP to make them happy which, AFAIC, is a step backward.

-Hal
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It also allowed it to get into the HCFC market that had been owned by AC for where flexible cable was allowed.
 
garbo said:
In my area ( no state electrical license ) appears that most towns require far superior type MC cable must be used in non residential locations rather then flimsy AC cable with its very small guage bare wire touching the convolutions to provide the ground. Wish the NEC would do away with AC cable. Worse most dangerous misuse of type AC cable was somebody ran 14/4 AC cable off of a two phase panel to supply four 20 amp fused circuits to office receptacles. They used the metal jacket as the grounded conductor. It ran thru one damp room that caused the steel jacket to severely rust. Jacket was hot to the touch. Replaced it with conduit.
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Ac is supposed to have a meteal liner inside the metal jacket so not just the jacket is used as EGC but i dont know the benefits of mc vs ac or vise versa. They look the same
 
Jpflex said:
Ac is supposed to have a meteal liner inside the metal jacket so not just the jacket is used as EGC but i dont know the benefits of mc vs ac or vise versa. They look the same
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It's not a liner, it's an aluminum conductor that's in contact with the coils of the sheath along it's length. MCAP as well as AC has one.
 
roger said:
It's not a liner, it's an aluminum conductor that's in contact with the coils of the sheath along it's length. MCAP as well as AC has one.
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Correct and the bonding strip in AC is only there to connect the helical coils of the armor to each other. For it to perform as an EGC it probably doesn't even need to be continuous. I have seen it broken within the cable.
 
electrofelon said:
I feel the opposite and hate MC cable. Such a waste and all that labor to terminate the egc's. Just another example of everyone going nutty with grounding despite zero evidence of issues.

Someone could miss use MC and use the sheath as the grounded conductor too.
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So AC has not EGC to terminate but AC has the bonding strip? What happens with the bonding strip?
 
infinity said:
When correctly installed there is nothing wrong with AC. Now with MC-ap there is really no difference between AC and MC-ap.
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Why is there no difference between MCAP and AC? Or better yet what is the difference between regular MC and MC AP? Both have MC's have full size ground.
 
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