When Your Copper Cable Certification Fails, Don’t Jump to Rip-and-Replace — Troubleshoot With the WireXpert 4500 Locator Function
After spending a lot of time and effort installing hundreds of copper Ethernet cables, the last thing you want to learn is that your cable failed certification testing. Certification failures often precede a time-consuming headache of troubleshooting — checking terminations, connections, cable grades and more. This process quickly drains time and resources. For example, if it costs $6 per link to install and you then spend a half hour finding a problem, you've blown your budget. But if you can quickly find the fault location, actions can be taken to help keep project costs in line.
To minimize project downtime and lost revenue, it is crucial to find the point of failure as soon as possible. But if the source of certification failure isn’t found, the dreaded rip-and-replace may be the only fix — further increasing wasted time, labor and costs.
The WireXpert’s locator function provides a quick, simple solution to the challenge of locating failure points within your installed Ethernet cable — helping technicians save time while reserving rip-and-replace as a last resort. Here’s a brief overview of the WireXpert locator function.
WireXpert Locator Function
The WireXpert 4500 locator function enables technicians to easily find and troubleshoot near-end crosstalk (NEXT) and return loss (RL) failures in order to meet stringent certification requirements.
Installation Issues That Cause Certification Failures
Physical misuse — including pulling, bending or twisting the cable beyond its specifications — is often the cause of NEXT and RL failures. When the cable is physically damaged, its geometry is destroyed. At the site of the damage the cable’s impedance is non-uniform, which affects its performance.
Detecting Certification Failures
The locator function determines where the site of non-uniform impedance is by sending an incident signal down the line and detecting frequency disturbances. The WireXpert then converts this frequency data into the time domain, which provides the actual distance between the source of disturbance and the WireXpert. This allows the technician to immediately find the source of certification failure.
Meeting NEXT certification requirements is a challenge and is the most likely test to fail. NEXT is the signal interference between cable pairs, when the signal of one pair is picked up by an adjacent pair.
Many simple issues can cause NEXT failures, such as physical damage, incorrect cable and connector pairing, poor terminations and poor overall cable assembly quality. Keep in mind that if a cable fails NEXT testing but passes every other certification standard, it can still operate in a minimal performance application. In networks that require a higher degree of performance, NEXT certification is necessary.
When the WireXpert locator detects RL issues, it measures the return loss per pair and throughout the length of the cable. For example, it can provide a readout that RL is highest at the far connector on the 1,2 pair on a faulty cable. The locator function enables technicians to find the kink, bend, break or other issue that is causing the return loss and fix it.
Finding the distance to the fault that caused the certification test failure is exactly what the locator function does, allowing technicians to reserve full replacement as a last resort.
When using the locator function, the WireXpert displays an xy-plane to plot each cable pair’s performance. The x-axis shows the length of the entire cable, originating at the 0 ft mark, while the y-axis represents the value of the parameter of interest, such as NEXT or RL.
WireXpert Product Demo
WireXpert’s locator function provides an easy and fast method for identifying cable problems and locating the distance to the problem. Easy and fast troubleshooting tools like the locator can be the difference between achieving project margins — or not — when the problem-finding clock starts.