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Cat 5e distance 1

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eanda10

Programmer
Apr 9, 2002
141
US
What is the maximum distance for a cat5e (350mhz) run and still be able to get a 100baseT connection and to be in spec.?

my instatler is telling me 200 meters is this correct?
 
It is 285 feet. I beleive that is 100 meters.

Mike Jones
LSUHSC
 
100 meters, which is 328 feet.
Normal recomendation is not to exceed 300 feet per run.
That way you still have additional for patch cords.
 
the 200 meter figure is way off

you can run 100 meters install a switch or hub to act as a repeater then go another 100 meters if you need the distance

the 100 meters includes the patch cords so you have to factor that in .
 
The permanent link which is the solid conductor from patch panel to jack is 90 mtrs or 295 ft.
You may have 10 mtrs of stranded (typically) patch cord and equipment cords totaling 100 mtrs or 328 ft for the channel.

By the way, Cat 5e is not 350 Mhz it is only 100 Mhz same as Cat 5, but with Cat 5e you are using all 4 pairs to acheive 1000BaseT (Gigabit) performance, unlike Cat 5 which only uses 2 pair for 10BaseT or 100BaseT.

Cat 6 is 200 Mhx tested to 250 Mhz, and uses all 4 pairs.

Richard S. Anderson, RCDD
 
the wire we used was rated at 350mhz and was marked cat 5e
 
A manufacturer can mark a box anything he wants, the standard rates Cat 5e at 100 Mhz.
Don't believe all the marketing hype. Read the standard and you will see only 100 Mhz for anything less than Cat 6 in copper.

Richard S. Anderson, RCDD
 
Cat5E requires 100MHz to operate, and it does indeed operate within that requirement... but a manufacturer can test their cable to 350MHz and write that on the box... so are you saying that they're writing 350MHz when it does indeed not function at that high of a frequency? I'm not clear on what you were saying.
 
Berk-tek’s Landmark 350 is a CAT5e cable tested to 350 Mhz. They say it was independently test verified.

What does it mean? – they make great cable. Of all the factors that affect transmission (microbends, copper consistency etc.) you will get very little problems from this cable versus others who barely meet the minimums. The certification is still only 5e.

In one CAT5 case, we had several locations beyond the 100 meter limit. The customer did not want electronics to extend the limit. They agreed to CAT7 cable without the certification for those locations. The extended length (450’) CAT7 performed just as well as the CAT5 cable within limits.


Regards
Peter Buitenhek
Profit Developer.com
 
Are the electronics built for more than the standard says?
NO, so does it really matter? Not really, the manufacturer can test his cables to a higher bandwidth sure, but does it mean it can carry more data than the elctronics will provide, which are built based on the standards?
If a cable is Cat 5e compliant it will perform to the standards.

Here is a link to an article in Cable Installation Magazine, you may have to register with their site to see it, but they do have a great magazine for our industry.


Hopefully the link works.

What was this Cat 7 cable constructed of?
Exceeding the distance limitation can have effects the you can't compensate for due to delay propagation and delay skew.

Richard S. Anderson, RCDD
 
I read that link you posted and I still don't understand. It says that Belded made cat5 cable that exceeded cat6 standards, so does that mean I am going to get cat6 performance on that cat5 cable. Can I put cat6 ends on those runs and have a tester certify that cable to cat6??

The article seem to focus on the confusion the ratings give in comparison to the standards needed.
 
I never said that the equipment would utilize the higher bandwidth capability of the cable. I'm trying to make the point that regardless of whether or not it's being used at 100baseT, or gigabit, that it was tested to 350MHz which gives it more headroom. That being said, in rare instances where the cable is some how affected, etc. etc. etc. that headroom can be helpful.

Would I rather buy cable that's been tested to 100MHz or 350MHz if it's only going to be used in a spectrum up to 100MHz? 350MHz of course.
 
Bospruell: If the cable exceeds the cat6 standards and passes cat6 testing when installed then, yes you can put cat6 ends on it and use it for cat6 applications. The only thing is it's not CERTIFIED for cat6 but that may not matter in your situation.
 
When I visited the Amp Cabling Plant many years ago I was amazed to see the cable making equipment. My biggest wow was when they told me that they tested every xx thousand feet and if that cable passed CAT5e then it was labled CAT5e, if it only passed 5 it was labled accordingly.

Does anyone have any input into this same practice to date? This may explain why the cable is tested to 350 Mhz, but gets a CAT5e rating.

Richard - The 450' CAT7 cable was Belden plenum and passed all CAT5 standards per the tester after install. Yes, the tester was certified and properly calibrated. My only explanation was that the superior cable material and construction actually helped. The 7 locations each had smart hubs attached. The network did not show any unusual overhead activity.

Regards
Peter Buitenhek
Profit Developer.com
 
Peter

I was more curious about the Cat 7 composition, since I haven't seen much available in the market. Or was it Level 7 from Anixter?

Also, what you mentioned about manufacture is true for most companies, which we discussed quite a bit in regards to SM and MM optical fiber connectors a while back.

It is the same stuff in many cases. Several manufacturers a couple years ago were touting their 200, 250, 350 or 400 or whatever cable and at the same time talking down even their own "normal" 100 Cat 5e as "minimally compliant" they didn't do that because it did not pass the tests, but because the margin wasn't as good, which is demonstrated by your comments about your tour Peter.

Back when manufacturers were making these claims I did some testing in as controlled environment as I could, and for the most part there was not a real difference. I will see if I can find any of those tests and post them later.


Richard S. Anderson, RCDD
 
Richard,

No the cable was not part of Anixter’s Level 7 program.
The cable was manufactured by Belden and was listed as CAT7. The install took place several years ago in both California and Alabama. The cable was bonded and had a crescent shape. The 1K box weighed about 1.4 x that of a regular cable (presumably due to greater copper content).

Responding to a question at another forum about cost of poor cabling:

What is cost of poor cabling?

My answer was:
The cost of poor cabling 1/1000 of good cabling.
Tested older CAT5 (poorly installed) cable and discovered 100,000 bit error rate per 1 million sent on cable that was 395' (over limit). Installed CAT7 Belden cable and BER went under 100 errors per 1 million sent. This translated into dramatic reduction in re-transmissions which resulted in access time to network in seconds versus 1-2 minutes.

Since no other changes were made (electronics wise to the above mentioned), this prompted us to try the longer 450’ runs in Alabama. Although the BER did go up slightly versus the 395’ it still was within the customer’s expectations.

The intent of the thread was not to propose using longer lengths indiscriminately. We put a lot of effort into the CAT5 designs and found a great work around that proved effective. The manufactures are truly designing their newer cables for optimum performance. Back when we did the install, I am certain many of the proposed (future CAT7) standards limits were ETHER (vapor) and Belden designed for the max.

The customer was aware of the length limitations and was willing to proceed knowing the cables would not pass “standards”. The Standards Police were not happy with this install.


Regards
Peter Buitenhek
Profit Developer.com
 
Peter...LOL

Thanks for the info, Cat 7 should be a screened and shielded cable...i.e. Overall screen and shield around individual pairs. Which would certainly make it heavier.
I would be curious if it was indeed Cat 7 if the shielding provided more protection that enable the better performance.
Well, maybe I don't want to start that...I hear a theory argument starting..
Usually when we go long we go with fiber, but that sounds like something worth looking at in those extreme cases.
Just curious about the cost difference to putting in a switch and repeating the signal over the cost of that cable and repulling and terminating?

Richard S. Anderson, RCDD
 
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