Optical Time Domain Reflectometer (OTDR)
Optical Time Domain Reflectometer (OTDR) The Optical Time Domain Reflectometer (OTDR) is useful for testing the integrity of fiber optic cables. It can verify splice loss, measure length and find faults. The OTDR is also commonly used to create a "picture" of fiber optic cable when it is newly installed. Later, comparisons can be made between the original trace and a second trace taken if problems arise. Analyzing the OTDR trace is always made easier by having documentation from the original trace that was created when the cable was installed. OTDRs are most effective when testing long cables (more than aproximately 250 meters or 800 feet) or cable plants with splices. The data that the OTDR produces are typically used to create a picture called a "trace" or "signature" that has valuable information for the trained user and can be stored for later reference or to check against a blueprint when network trouble arises. OTDRs should not be used for measurin...