Common Causes of Cable Installation Failures 

Before diving into troubleshooting, it's helpful to know the usual suspects. Some of the most common reasons a test fails include: 

Poor terminations – Loose or incorrectly crimped connectors 

Excessive cable length – Exceeding the maximum Length affects performance. 

Crosstalk (NEXT, ACR-F) – Interference from adjacent cables 

Return loss – Signal reflections caused by impedance mismatches 

Damaged or kinked cables – Physical damage impacts performance 

Once you've identified the issue, it's time to fix it. 

 
 

Step-by-Step Troubleshooting Using a DSX-5000 or DSX-8000 

Run an Autotest 

The DSX-5000 and DSX-8000 feature an Autotest function that quickly evaluates the cable's performance. If it fails, check the detailed report for error specifics. 

Analyse the Failure Details 

If the failure is Near-End Crosstalk (NEXT), look for tight cable bundling or untwisted pairs near terminations. 

If the failure is a Return Loss, check for mismatched connectors or kinks in the cable. 

If the failure is Length, ensure the cable run is within limits (90m for permanent links, 100m for channels). 

Inspect Physical Connections 

Sometimes, the problem is as simple as a bad termination. Check that all connectors are properly crimped and fully seated. 

Re-run the Test After Fixes 

Once you've corrected the issue, test again. If it still fails, review the results carefully; sometimes, multiple minor issues compound the failure. 

Save and Document Results 

If you're working on a project, permanently save your test results. The DSX tester allows you to generate reports, which can be helpful for quality assurance and client handovers.