An ideal differential network cable pair has 100 ohm impedance along the entire length. In reality, the impedance varies from 100 ohm in different amounts along the cabling link, the deviation being more significant at the positions of connectors. Return Loss (RL) Locator plot provides a view of the cable along its length. The locations of peaks in the RL Locator are representative of spots with poor impedance control. When a cable fails autotest, the RL locator helps determine the TDR or distance to fault location along the cabling link that is most likely to have caused failure.
This is a great aid for trouble-shooting. With accurate location information of the problem spot, a technician can focus on fixing the issue on that part of the cable, whether it is the result of:
- Impedance mismatch in components (non-compliant or damaged cable, inadequate cabling installation practices, too much tension on cables, kinks or non-compliant connecting hardware/patch cords
- Improper termination practices (pair twist not maintained, excessive cable sheath removal)
- Incorrect or substandard components (all cable & connecting hardware must be of same category/class/quality)