Hi all, Would anyone know the exact twist rates in a cat6 cable? Also will a twisted wire pair run along the length of the cable or is it twisted internally as well.Hope this query makes sense.Thanks in advance,
Sriram
Each pair is different.
Twisting mostly cancels out inductive (current based) coupling over a long cable. Think of an untwisted pair as a very long and narrow loop, which will generate a magnetic field when current runs through it.
If it is near a similar loop, current will be induced in that loop. With the twist, half the time the loop (and magnetic field) will be in the other direction.
Two twisted pairs with the same pitch (twist rate) near each other would easily arrange so that the twists cancel out and the currents add up. Having different pitch means that on average over a long cable they pretty much cancel out.
There may also be an overall twist, but it has a very long pitch, and doesn't contribute much. It might help a little against coupling between nearby cables, though.
-- glen
The Belden catalog used to specify the twists per foot of each of its type of cables. gr
The query does make sense. Yet you have to realize that most vendors actually patent their twisting schemes and other cable design details. So, if you are simply copying the twist lengths, you are pretty much infringing on their copyright. They want you to put up your own multimillion dollar lab and design your CAT6 cables there.
Cheers! Dmitriy
-------------------------------------
##-----------------------------------------------## Delivered via
Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.