|You can also click here to see a video of Adrian Young from our Technical Assistance Center walking you through these steps. |
In this case study, the installer was failing Return Loss when certifying a number of category 6 permanent links. With the DTX CableAnalyzer, it is possible to discover why these links were failing.
After the AUTOTEST, the installer was presented with the following DTX CableAnalyzer test result.
Your DTX CableAnalyzer can help you diagnose the failing Return Loss result. Let's review the process. Do not skip Step 1 please.
Find out which pair is causing the FAIL.
Here we see that Pair 7,8 is failing, The trace passes through the red limit line. As a rule of thumb, if we see Return Loss fail at the lower frequencies, it suggsests a cable issue. (Assuming Resistance is good, which it is in this case)
Look at the HDTDR Analyzer trace for this marginal pair.
As a rule of thumb (not in the standards), we do not want to see any events in the cable exceed 0.8 or -0.8 which is roughly half way up the vertical scale (hence the 64X zoom). Clearly we see too many events exceeding 0.8 and -0.8 in the cable. What makes this trace interesting is that the middle section of the cable looks to be good. This suggests that the cable was damaged during the installation. It is not always this obvious.