MC/AC Clamp in bracket boxes

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""Hospital Grade AC" although, it is a somewhat common term"

I totally understand that, as it is really just a appoval code.

I do have the data on HCF, and I will dig into it. We don't use the stuff yet in my jurisdiction. Everything here is done economy syle, and it is a constant effort on my part to get the best materials in here and eliminate some of this Chinease garbage that get's in, as the recent mess with GFCI's indicated.

I'm sure the stuff is just great and top notch, but Square D is a rarity in these parts unless you are dealing with the best electricians. I never used anything but, and all Leviton devices as well, but the market is different here.

My only point for arguing this, is that most AC is indeed legal, and the fittings are really important.

I'll look up the data on the others. I have only seen one MFGR's stuff and I have the book.
 
roger said:
Wirestripper, you still have not accurately described the difference between AC and HCF, the sheath is only part of the equation in Patient Vicinity's.

There is no such thing as "Hospital Grade AC" although, it is a somewhat common term. I'll point it out tomorrow if you haven't found it by morning.

Hint, regular AC can be used above 7.5'


Roger
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OK Roger, ya got me.

What I just read, some data from AFC, or Tyco MFG is that their AC Cable constuction is identical to the HCF except for a green colored ground wire.

Ground wires can be created in the field on AC and most MFG's make a number that has one included in their AC lines of cable, specifically for equipment grounding. I could not find any other differences at all, including the wire quality and sizes. The sheath was identicle as was everything else. Just the green to satisfy the redundancy requirements which is really all we are talking about.

So what is the 7.5'? (see ya tomorrow)
 
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Roger, I am a bit of a perfectionist, and I went to bed, still tying to decifer where you were going with your comment about 7.5'.

I came to the conclusion that you are refering to what I call the six foot rule, where when used as a equipment ground, manufactured flex conduits that do not meet the grounding standards for safety, must be limited to 6 or 6.5 feet.

But AC does, and HCF or Hospital facility grade AC cable does as well. The cable would have a redundant ground however and is quite suited to motor or fixture grounding.

Both cables are run in exactly the same way. In fact, HCF is only a grade of AC and that is quite clear to me. What a manufacturer decides to call it's AC with ground is not really worth arguing. They should really call it MCF, Medical care Facility cable, to be more specific. We use it in Dentist offices and out patient clinics. But then we use it for other purposes as well, where redundant grounding and possible human contact with the conduit or the downline devices are indicated for safety reasons.

Good night......

Mike
 
Good morning Mike ! Hope you had a good night sleep.
I will help you with Rogers 7.5' look at 517.13 (B) Exception No. 2
Now you can have another sip of coffee! Maybe a dounut or two.
The differences between AC and HCF is that HCF has an Insulated ground. Both the armor of AC and HCF is suitable for ground but in patient care area you have to have the insulated ground and that type of cable is called HCF cable. As Roger said MC came out with an approved cable for parient care area.

You say that the Vendors don't carry the right stuff out there and they don't like you for telling them to. You may want to start by telling them about HCF cable now that you know about it. When you got the fax from the cable company did it not have the trype of cable it was? It should have said what type it was.

Anyway------ This site with guy's like Roger, iwire, charile, and the list goes on are of great great help. You will learn something new everyday as I do and I have been in the contracting business for 30 years and I am still ashamed on what I don't know.
I wonder what we would do without the Internet and a site like this.
I will tell you one thing it has educated many people including myself.
THANKS GUY'S
 
roger said:
Fc, boy, that took me a long time to type, you hadn't posted when I started, I didn't mean to be redundant. ;) (as in grounding) :D

Roger
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LOL: That's OK you tell it better then me ! or I should say your ground in connected mines a little loose!
 
Rick Haupt said:
Is there a requirement that bracket boxes that have the internal MC/AC clamp be used on 250volts or less only? Or is this a jurisdictional item?
I have always used standard boxes with ko's and external clamps on 277 swicthes.
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Getting back to the first question

I know of no requirement unless in your jurisdiction there is.
 
Mike
With the advent of the new type of MC cable that is now on the market and available in sizes 14 WG - 10 AWG and soon to have larger sizes, the use and sale of AC cable will go "by-by".
The new style MC cable was designed to help manufacturers, supply houses and contractors be able to stock only one cable type. Now the use of AC will not be necessary and the word in the manufacturing sector is that in 3 years or less AC cable will no longer be manufactured, only MC type will be available.
In a lot of the supply houses here, MC cable is slightly less $ per 1000' than AC cable is, and the contractors are buying MC cable.

As an inspector, there a lot of installation "issues" out there. You seem to be fixated on this MC/AC thing. How do you handle all of the other issues?
Don't get me wrong, it is good to see an inspector who cares about the industry and the men, I am just curious how you handle all of the other issues that must pop up.
 
"Don't get me wrong, it is good to see an inspector who cares about the industry and the men, I am just curious how you handle all of the other issues that must pop up."


Not a fixation, but more of a aggravation or irritation.

It's not the materials, it's the various and variable terminologies.

For years, there has been a AC cableing system that can be ordered with a green ground and is therefore approved for hospital uses, but I come here, or wherever and mention this and I'm told by people in the know that HCF is the proper cable and it is not AC.

I'm sorry to say that I don't agree. It is AC......

1. The code does not refer in any way to HCF.

2. The code does refer to AC and does list it as approved for healthcare if it meets certain conditions.

3. AC refers to the cable armor construction, not the wire within. All of it is THHN.

4. Therefore, the code recognises that HCF is AC cable and in order to "keep it simple stupid" it has declined to mention the various labels used by the industry.

5. HCF is very simply put as AC cable with ground.

The following is a paragraph from the AFC cable systems pocket guide that is mentioned quite often on this forum, so I use it as a demonstration since everyone probably has seen it of has it.

This is on the top of page seven and I quote verbatim......

"Type AC cable is available in standard AC, AC-Lite (aluminum) or Health Care Facilities Cable (AFC's and KafTech's HCF-90 and it's aluminum version HCF-Lite)

HCF, or Hospital Grade cable, is constructed in the same manner as standard AC cable, but with the addition of a green grounding conductor."

It then goes on to explain the relation to the various code sections and why it meets the requirement for healthcare.

It is the manufacturer who labeled and named this version of AC and as per usual, the terminology debate rages on, as it did with BX and the numerous descriptive terms that electricians like to employ.

Just like Doctors and other proffessionals, we pride ourselves on our knowlege of terms and love to see it happen when someone shakes their head and says, "what are you talkin about?".

The code had to read through all this and get back to bascics, where it refuses to mention HCF and treats it for what it is, a redundant manufacturers term, lie a set of Klines, Dikes or Duck Tape.....Even a Wiggy!:)

All I try to do, as a representative of the code, is to force the conversation back to basics where everyone is on the same page. And that is all I am trying to do now, and like a pit bull, I rarely relent when I know that I am right.

HCF is indeed a version of AC.

And although I have never laid eyes on this new Hospital grade MC, I can probably predict that it is a new version of AC cabeling because the term MC and bonding jacket are not synonomous as it is with AC, so it must be constructed like AC cable and would be viewed by most as a confusing term to use and the code would be required to address it if problems persisted in the field.

This sort of thing is one of the inspectors worst nightmares when it comes to avoiding misunderstandings. We need to use the correct term to define what we do. When several brand names become synonomous with descriptive terms, the communications suffer.

I was once asked by a job forman if I had had much experience with "RobRoy"?

I was working in various parts of the country, but the term eluded me and I did not want to appear stupid, so I said yes....I assumed he was asking everyone the same question.

This time it turned out fine, because about ten minutes later I saw a truck enter the gate with a rack loaded with "Plasti-Bond" and I had bent, cut and threaded tons of the stuff for Brown and Root. But others were not so lucky, and I soon discovered that I was the only Journeyman with experiance on that pipe, and I had to tutor everyone else. It caused delays and the job time was slower as a result of learning the devious nature of this product.....:)

So yes, terms are important.

That's about all I have to say on the subject, and I think I'll leave it at that.
 
I appreciate the kind reply Fc.....

But I know all about the wire diferences and why.

The distribution of Tyco or AFC products is non-existant in my area, and prior to my retirement from my tools in 2000, I had never heard the term HCF used, we ordered Hospital grade AC. It comes with the required ground and to the best of my knowlege, some manufacturers are still doing this and do not separately label their hospital grade product.

It's really not all that important, unless you are trying to communicate, which is what I have to do a great deal of the time.

I promise you, that when the code says HCF, rather than AC, I will begin to call it that and the term will be a part of my vocabulary. That may or may not happen. I just don't know.

In the mean time, I don't want to add further confusion, but I do understand that the two descriptions are synonomous.

If you were a inspector, and you inspected a small addition to a hospital, like the installation of a new room, and during the inspection you saw a piece of AC cable with the proper fittings and one of the wires was properly taped with the green phase tape on both ends for a equipment ground. Would you pass or fail it?

Would you make the electrician jerk it all out and by some other product? Or would you recognise the legality, but get a bit angry that the vendor did not carry the right stuff for a neat and tidy installation.

I did pass it, and I did get angry with the vendor. We should be able to do the things we need to do, in order to build a safe and attractive job when we sign our name on it. The lead time on the cable was far too long to get the job done on time, (4-6 weeks) or a huge premium had to be paid which would have taken much of his profit from the job, and the electrician that did it was frustrated and I understood how he felt.

Nobody wants to do that. But it is a reality that I have to deal with out here in the boonies.....And I do it....

But I do it safely and code legal. As per Art. 250.119-B 1,2 and 3

These are the realities of the job, and although it is nice to order a special assembly system from a big vendor, we more likely have to build it ourselves and do it right, which the code allows.
 
Fc, thank you for the kind words.

Wirestripper, to help you with your better understanding of the difference in the plain Jane AC verses HCFC and where HCFC must be used, click on the link below. Also,
Yes, I heard about that stuff, but I have yet to see it. If it is true MC, then it would have a steel jacket. If it is aluminum with a stringer, then it seems to me to still be AC.
Click to expand...
note the steel jacket.

Patient Area Bonding

Roger
 
And that is all I am trying to do now, and like a pit bull, I rarely relent when I know that I am right.
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Such confidence, I basically agree with you this time, but believe me there have been times when "I knew that I was right" when I was not right. It can be quite a humbling experience.
 
I understand what you are saying Roger, but we seem to be going in circles...LOL

MC is indeed steel, and that is not one of the best conductors.

AC in it's basic form has always been aluminum, in my past memory, but there seem to be some MFG's that make a different jacket, that may or may not conform to the NEC bonding rules for healthcare. I have always referred to this AC as a lower cost alternative or mislabeled MC that without UL approvals cannot be used for Healthcare and I watch for it in the field, but frankly we do so little healthcare stuff, maybe once or twice a year, that it has not turned up.

I do understand your point about AC cabling, and that it is possible that AC is not always a effective bond because of the type. But as a general rule, AC meets the requirments and to order the wrong kind would certainly be a big mistake. But I have never had to deal with that. The AC I see is always aluminum and does meet the code requirements per the MFG and the vendors.

They use the term, Hospital grade, and that is the term we use, or have used for decades.

The next time we expand our Hospital or build a clinic, that may change because there seems to be a effort to deem HCF as being the terminology to use. But the code still does not recognise it specifically and the last I checked, there were MFGr's making hospital grade AC.

The next time I am over at the local vendor, I will see what he has. But as far as confusion on my part, there is none. The contractor always must furnish proof to me that his materials meet the specifications for the job. I need only ask for that proof. and have done so in the past.

I also pick up clippings to examine the wire and the jackets.
 
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dlhoule said:
Such confidence, I basically agree with you this time, but believe me there have been times when "I knew that I was right" when I was not right. It can be quite a humbling experience.
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I have done that.........You bet!

And it is hard as heck to admit you are wrong, but I will and I have done so on occassion. But I do fight hard for my positions. It is my nature to do so.

If I am, proven wrong here, I will submit my apologies. Sooner or later, that will happen.
 
wirestripper said:
I understand what you are saying Roger, but we seem to be going in circles...LOL

MC is indeed steel, and that is not one of the best conductors.

AC in it's basic form has always been aluminum, in my past memory,
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Now here goes my age again "In my day that's all AC cable was Steel.
In fact I seen it delivered to one of my job's just the other day and the foreman refused it. He said "we don't handle the heavy stuff anymore"
So it's still can be had.
Ah------------the good old day's !! Thank God there not here anymore.
 
That's good to know....

With prices being what they are, there is all sorts of stuff appearing, according to the skip I have been getting from the State.

They still ship aluminum wired mobile homes into this state. I think we finally eliminated them, but you never know...

You should see the Katrina cars!

Marketing has few rules.
 
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