Mc/ac wiring

[Alwayslearningelec]

Ok the difference between the the two is that ac uses a bonding strip which enables the jacket to be used as a ground and mc has a full size ground. In commercial work wouldnt it make sense to wire branch circuits receptacles sect with ac and not mc???? Thanks

 

[jmellc]

Good question. I never used much AC. True, the grounding is simpler. However, AC has to be supported every 4 1/2 feet and MC every 6 feet. With long runs, that can make some difference in labor. Not sure on cost difference, as I've never bought AC. AC requires bushings too, or bushed connectors, which are optional with MC.

I'm sure someone here has worked with both & can enlighten us

 

[ActionDave]

Ok the difference between the the two is that ac uses a bonding strip which enables the jacket to be used as a ground and mc has a full size ground. In commercial work wouldnt it make sense to wire branch circuits receptacles sect with ac and not mc???? Thanks

It would until you spend a day working with it.

 

[iwire]

Ok the difference between the the two is that ac uses a bonding strip which enables the jacket to be used as a ground and mc has a full size ground. In commercial work wouldnt it make sense to wire branch circuits receptacles sect with ac and not mc???? Thanks

Sure, and we used to use a lot of it. It is still NEC compliant for many uses. I liked working with AC, less connections to make in each box.

The problem is that many job specifications require copper wire EGCs and MC.

 

[bphgravity]

From a code standpoint there are only a few minor differences between the two similar products.

Type AC can only be used in dry locations and never in damp or wet locations. Type MC is sometimes permitted in damp and wet locations. The supporting and securing requirements are more restrictive for Type AC verses Type MC. Anti-shorting bushings are required for Type AC and not for Type MC. And then you have the equipment grounding adequacy of all Type AC but only certain Type MC products.

Reference the .10, .12, .30, .40, and .108 sections of Article 320 and 330 of the 2011 NEC.

 

[infinity]

From a labor perspective AC is easier and faster since you don't have to terminate an EGC at every box, fixture or panelboard, although the thinner jacket on MC is easier to strip. MC-ap has the best attributes of both types of cable.

 

[Alwayslearningelec]

Thanks everyone...good stuff. THat may have been one of my better questions :grin::roll: