atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Fluke DSP-4300

I have a DSP-4300 tester. Were testing Cat 6 UTP cable using the channel adaptors with Cat 6 patch cables on both sides (station/patch panel). 4 of the 46 cables failed NEXT@remote. What I found is when I switch patch cables on the station end they will pass. BUT, If I take the patch cable that failed to a known aready tested cable and run a test it passes.
Question - Is the tester to sensitive? Any suggestions?

RTB -

What were the readings on the cables that failed vs. the ones that passed? Perhaps the failing cables and patch cords were just marginally OK and the combination of the two was just enough to push them into failure.

The same applies to the stations that passed - If they had a lot of "fat" in the readings, then a marginal patch cord might not have been enough to push them over the edge.

Cat 6 testing is a whole lot tougher than 5E so be prepared for stuff like this.

By the way, Cat 6A and Class F (Future Cat 7) are hideous to test. Way worse than 6.

Sam

I've had issues like that with my DSP-4000, but they were solved by doing the calibration. It seems to happen after switching between basic link and channel adapters.

Do you have the calibration module, and if so, did you run it through the calibration?

Are you using the same brand for patch cords as you are for your channel? I've seen issues with that in the past. I would recommend the Permanent Link Head and elimanate the patch cords when testing.

Also - how old is the tester? It maybe due for its yearly factory calibration.

Jeff

Are the cables that failed short runs? Less than 50'?
I know some manufactures spec that runs need to be at least a certain length. Sounds kinda crazy, but I have experienced it on a run less than 20'.

I've also had problems on very short runs. The circuit is too "hot" for the tester. Not all testers, but I can't remember which one gave us grief.


Sam

Thanks for all the advice!
1. The DSP-4300 was just returned from Fluke for it's yearly calibration. Funny that was mentioned.
2. I did calibrate it with the module and then tried the test again.
3. I have experienced the too short of a distance issue as well.
4. Sam - I think your write on with the marginal patch cable suggestion. Thats probably what it is.

I have installed a ton of Cat 5E. It's been awhile since I installed and tested Cat 6. Now I remember that it's a different animal. Cat 6 is finicky!
Thanks again!
RTB