Stripping Large Type TC Cable

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Just curious; is there actually a market for TC-ER for 500 kcmil and larger. Personally, I would never design for a multiconductor cable construction for tray installation in those sizes. In fact, I would rarely go for single-conductor tray installations in those sizes.

If you go back to the late 90's, early 2000's NEC documentation, you will find I was a major proponent for what ultimately became TC-ER. At the time, it was the manufacturers of MC that was opposed to it since it was expected to cut heavily into their market. It sounds like making a large conductor TC-ER that meets the crush/impact of MC is more or less futile especially if even a moderate ease of installation is a consideration ("-ER" or not).
 
rbalex said:
Just curious; is there actually a market for TC-ER for 500 kcmil and larger. Personally, I would never design for a multiconductor cable construction for tray installation in those sizes. In fact, I would rarely go for single-conductor tray installations in those sizes.

If you go back to the late 90's, early 2000's NEC documentation, you will find I was a major proponent for what ultimately became TC-ER. At the time, it was the manufacturers of MC that was opposed to it since it was expected to cut heavily into their market. It sounds like making a large conductor TC-ER that meets the crush/impact of MC is more or less futile especially if even a moderate ease of installation is a consideration ("-ER" or not).
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HUGE market as we are selling TONS of it....which has spawned the need to provide an easy trimming alternative to the knuckle buster approach. We are seeing a lot of this being used in data centers as well now days. As for the market...the easy way to skin that puppy is to make both MC and TC....which we do so both add to sales.
 
MasterTheNEC said:
...As for the market...the easy way to skin that puppy is to make both MC and TC....which we do so both add to sales.
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It was the manufacturers that made both the were the major opponents - back in the day. They didn't want TC-ER cutting into their MC business. It's one of the reasons for making some of the more "unusual" (and unnecessary IMO) restrictions on TC-ER. But I haven't dealt with the issue since the 2001 NEC, so I'm rusty.

Nevertheless, huge market or not, it sounds like overall poor design if it's hard to install. "Time is money" and, in the size of projects I used to deal with, I would be getting HEAVY feedback from my field if they were even having modest installation issues.
 
rbalex said:
It was the manufacturers that made both the were the major opponents - back in the day. They didn't want TC-ER cutting into their MC business. It's one of the reasons for making some of the more "unusual" (and unnecessary IMO) restrictions on TC-ER. But I haven't dealt with the issue since the 2001 NEC, so I'm rusty.

Nevertheless, huge market or not, it sounds like overall poor design if it's hard to install. "Time is money" and, in the size of projects I used to deal with, I would be getting HEAVY feedback from my field if they were even having modest installation issues.
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Well I can only speak on volumes of sales as to the interest in the use of Type TC Cable. And again we sell alot of it in the larger sizes. The issue of installation is coming from the newer sales being driven by the product as the "Old School" installers have developed a technique that they are not sharing with the "New Cats" on the block which is why the increase in installation questions.

As for the limitations to the TC-ER, you will see those fall over the next few cycles because in most recent CMP meeting the use of Type TC-ER was lightened up for a specific use in a Single Family Dwelling to be installed without a raceway or cable tray for generator applications. The debate was very good and arguments said it was too much of a jump from the limitations in 336.10 to now allow in a residence but in the end it passed (not sure it will survive the ballot however) but the buzz on the sidelines was....lets reexamine at 336 next time and await public inputs that are sure to come by the next cycle.

It is not hard to install in a cable tray, if you design it right and set up your pull correctly and the increased jacket affords it additional protection in specific applications...either way people are buying it, it is no different than normal sized Type TC-ER Cable...just bigger of course.

Oh..I forgot to address the manufacturers opposition....not all companies who make MC and AC actually make TC cable as well...most certainly at that day and time. The investment into the large extrusion lines, massive cabling that was needed and the lines needed to produce it are vastly different than what it needed for MC and AC Cable.....so yes if the companies that did not have the capability to expand into that market would fear the expanded use....but that is slowly changing as each company thrives on expansion.
 
MasterTheNEC said:
We also ordered one of those and tried it....just could not cut that material on the larger Type TC Cables....was fine on the size shown in the video but the larger Type TC-ER with 500-750 kcmil was a no go....actually damaged the cutter as the jacket was so thick.......BUT again thank you for the suggestions as it helps confirm that the methods we have been trying are what others would have tried versus the old school KNIFE HACK treatment.
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I have another tool bought for stripping large cable jackets.... Slower, but effective. It is a utility tool more for medium voltage products. I will see if I can find it. . The can opener worked great on recently installed 3/C #500 VFD cable....as well as TC-ER... But only ran up to #250
 
Just out of curiosity, what basic type of plastic is your jacket on those sizes? Other smaller ones?
 
jtrezon said:
Here is the other tool I have that might work for you
http://www.ripley-tools.com/tools.php?tool=WS_64U&category=Primary Distribution (Overhead)
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Thanks jtrezon...

Yes, we experimented with a stripper just like this and due to the allowable tolerances of the PVC Jacket it would occasionally cut into the inner conductors insulation. Even if ever so slight we would not wish to risk a potential insulation resistance issue down the road so it was a no go on this as something we can recommend. In the hands of a skilled worker like yourself it may be fine but when we recommend something as a manufacturer we want to make sure we have a foolproof.
 
MasterTheNEC said:
Thanks jtrezon...

Yes, we experimented with a stripper just like this and due to the allowable tolerances of the PVC Jacket it would occasionally cut into the inner conductors insulation. Even if ever so slight we would not wish to risk a potential insulation resistance issue down the road so it was a no go on this as something we can recommend. In the hands of a skilled worker like yourself it may be fine but when we recommend something as a manufacturer we want to make sure we have a foolproof.
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The problem I have found with people that use that type is, they always want to set the blade depth so it cut all the way through the jacket. As a result, it nicks an inner conductor's insulation where there jacket is on the thin side.

What I suggest you try is using one of those type with the blade depth set only to score the jacket pretty close to all the way through at the jacket's thinnest point (you know, the maximum minimum thickness :p). Then follow the score with the type of tool I posted in #12 above.

If you want to get radical on the scoring, try one of these... :D
img_18_01.jpg.jpg

http://www.seof.co.jp/english/product/tool/pdf/HS_Cable_Sheath_Cutter.pdf
http://www.seof.co.jp/english/product/tool/pdf/HS_Cable_Sheath_Cutter_Type_S.pdf
 
Smart $ said:
Well the logic is sound!

There has to be a minimum minimum and a maximum minimum in order for the term average minimum to have any substance.

:angel:
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For this case, yes, but for a general mathematical problem with an infinite number of values there can be a well defined average (and even a finite standard deviation) but neither a maximum nor a minimum.
 
Smart $ said:
Please elaborate.
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Without going into too much detail, you can for example have a distribution of integers such that the bulk are grouped near zero, but there are outliers which are less and less common the farther you go from the center.
The result is that you can always find a larger number eventually, but the average is still a finite number.
For an example, you can look at a convergent integral over the range -infinity to +infinity and interpret it as a probability distribution.
 
I must be getting confused. We have a cable manufacturer asking how to strip their own cable. If I had a problem stripping a cable I would contact the manufacturer for advice and not go on the internet asking a group of random guys.

Call me sceptical if you like but I don?t believe a word of this.
 
GoldDigger said:
Without going into too much detail, you can for example have a distribution of integers such that the bulk are grouped near zero, but there are outliers which are less and less common the farther you go from the center.
The result is that you can always find a larger number eventually, but the average is still a finite number.
For an example, you can look at a convergent integral over the range -infinity to +infinity and interpret it as a probability distribution.
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But... and you should no there is a BUT coming if I have anything to say about it :D... the minimum minimum and maximum mininum of your example would be -infinity and the mean, respectively.

Now take that to the next order, as I understand the described requirement for jacket thickness by Master'. Your samples (values) have been cut in half, the lower half, and you take the average thereof. At least that's the mathematics version. A manufacturing tolerance can be specified differently.
 
I disagree that the maximum minimum would be the mean. But it would really depend on the definition of maximum minimum if there is an accepted one, as well as the details of the distribution defining the value at different locations.
 
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