AC vs. MC vs. MC Lite

[ron]

Other than the differences that become apparent when comparing AC and MC Cable in their respective code sections, such as the presence of an insulated grounding conductor in MC, support interval diffeences, uses permitted, etc. are there practical differences that are found while installing the two products as a basic branch circuit? Preferences?
And what is the MC Lite product found at many supply houses, and how does it compare with regular MC or AC?
I don't get to handle the products myself, but want to make an educated descision regarding the specification of those items in different situations.

 

[iwire]

Re: AC vs. MC vs. MC Lite

AC cable (Steel Jacket for grounding)
I used to install this a lot, not any now except for hospital grade AC (This is AC cable with insulated ground) We use this for IG circuits sometimes.

I think it is out of favor in my area due to lack of a copper grounding conductor, but it is a tough and durable product, heavy to work with.

MC cable (Steel Jacket NOT for grounding)
What we install some of the time, it is a tough and durable product, heavy to work with.

MC lite (Aluminum Jacket NOT for grounding)
What we install most of the time, one guy can handle 1000' spools of 12/2 and 12/3, and the light weight allows us to pull a few long home runs at a time, not so easy with steel.

It strips easily with dikes (kink, cut, and straighten) or rotosplits just a couple of turns.

Not so durable, if it is not supported properly or if you are to rough with it on the install it will kink. Limited use of connectors, can not be used with the set screw type of connectors.

Fire Alarm MC is always steel on the jobs I have worked, and gets expensive, they tell me 16/2 TW/SP F/A MC is 4 times the price of 12/2 MC

Twisted shielded also takes time to make entry into connectors with out shorting the shield to ground.

MC for feeders, the largest size I have used is 4/0-4 this is hard to install if you go at it like it is a branch circuit, but with some planning it can go in very quickly, a few pulleys, a good rope and enough hands you quickly run a 200 amp 3P 5W feeder complete.

Like most electricians we use Antishorts on MC even though not a code requirement.

We always order our spools reverse wound, this used to be harder to get but now no problem. There is a tremendous difference in ease of pulling armored cable depending on which way it comes off the spool, if you look closely at it you can see why.

Steel MC is what I would specify, if it was up to me.

Hope this helpful and not to rambling.

[ March 22, 2003, 09:11 AM: Message edited by: iwire ]

 

[ron]

Re: AC vs. MC vs. MC Lite

Since the manufacturers refer to the aluminum MC cable as MC Lite, is there a formal definition of MC being made of steel?

 

[iwire]

Re: AC vs. MC vs. MC Lite

I am not sure I understand your question, are you looking for what to put on a spec to make sure that Steel MC is what you get?

"All Type MC cable shall be of steel interlocking tape armor construction"

That in the spec would make it clear to me that you do not want MC Lite.

 

[ron]

Re: AC vs. MC vs. MC Lite

Spelling it out in a spec is the easy part. Sometimes chnages in contract occur without detailing each item, such as the type MC (or steel compression couplings vs cast). I was curious if Type MC automatically covered the steel aspect, or is no MC spec complete without a steel or aluminum choice. MC Lite is of course not covered in the NEC seperately from MC, so I was wondering why the manufacturer should call it differently (I guess I can call a manufacturer).

 

[curt swartz]

Re: AC vs. MC vs. MC Lite

Ron

If you just specify MC cable most likely you will get aluminum armor.

Southwire only manufactures aluminum armor MC and AC cable as far as I know.

AFC has 3 different armor available.
MC Steel
MC TUFF - Lightweight Steel
MC Lite - Aluminum

 

[amptech]

Re: AC vs. MC vs. MC Lite

My supply house stocks only alum MC/AC cable. They can get steel if you need it but nobody around here uses it. I discovered stranded MC last summer and now my supply house stocks it. It costs about $5.00 more per 250' roll than solid but it's a lot easier to work with and has become very popular around here since the supply house started stocking it.