×
INTELLIGENT WORK FORUMS
FOR COMPUTER PROFESSIONALS

Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Help me in weird insertion loss problem in cat6F/UTP

Help me in weird insertion loss problem in cat6F/UTP

Help me in weird insertion loss problem in cat6F/UTP

(OP)
Dear friends,
Recently I got a cat6F/UTP. When I run permanent link test on it with DTX1800 fluke analyzer, I get marginal insertion loss(-0.2dB) failure just at low frequency (~3MHz) on all pairs. In higher frequency, the insertion loss is good and fairly below the limit margin!!.
When I run the channel test on this cable, the test is passed and the headroom on insertion loss @250 MHz is about 10 dB for all pairs. Can you help me what is the problem? is it the cable issue or connectors.

RE: Help me in weird insertion loss problem in cat6F/UTP

Reterminate both ends preferably to new jacks/ports and retest. If that doesn't resolve it then it's possible you have some bad cable.

RE: Help me in weird insertion loss problem in cat6F/UTP

Could be Cat 6 copper clad aluminum cable. Check the resistance measurement and compare to what would be expected for copper at the distance and wire gauge of the cable. Also, scrape the copper and see if there is aluminum beneath. If it turns out to be copper clad, replace it with real Cat 6 cable.

RE: Help me in weird insertion loss problem in cat6F/UTP

Definitely check for counterfeit cable. UL-444 can be forged.

NEC 800.179 Communications Wires and Cables. Communication wires and cables shall be listed in accordance with 800.179(A) through (I) and marked in accordance with Table 800.179. Conductors in communications cables, other than in a coaxial cable, shall be copper.

The 2017 (and 2014, 2011, 2008, 2005) NEC code book clearly does not allow CCA for communications...shall be.

_________________________________
"Thank you for calling Technical Support. If you feel you have reached this number in error, please hang up and try again." ~Jane Barbe

RE: Help me in weird insertion loss problem in cat6F/UTP

In the same vein as the two replies above, what is the brand of the cable? Was it purchased from an authorized dealer?

I love2 "FEATURE 00"
http://dexman.webs.com/

RE: Help me in weird insertion loss problem in cat6F/UTP

Copper clad aluminum cable will exhibit the described behavior. At higher frequencies, due to the "skin effect", current crowds to the outside of the conductor where the copper is located and attenuation won't differ so much from an all copper wire. However, at lower frequencies, where current will be flowing in both the aluminum and copper cladding, the attenuation will be higher than would be expected from a solid copper wire. Aside from this, there is the issue of performance with PoE since aluminum has a higher resistance.

RE: Help me in weird insertion loss problem in cat6F/UTP

At this point we can all speculate until the OP responds...if ever.

_________________________________
"Thank you for calling Technical Support. If you feel you have reached this number in error, please hang up and try again." ~Jane Barbe

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members! Already a Member? Login

Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close