An OTDR trace helps characterize individual events that can often be invisible when conducting only loss/length (tier 1) testing. More advanced units can provide easy to understand Event Maps and loss values for individual components as well as the link.
An OTDR trace is a graphical signature of a fiber's attenuation along its length which provides insight into the performance of the link components (cable, connectors and splices) and the quality of the installation by examining non-uniformities in the OTDR trace. Viewing trace results is simplified with advanced features such as pinch and zoomĮxtended or Tier 2 fiber certification supplements Tier 1 testing with the addition of an Optical Time Domain Reflectometer (OTDR) from end to end. Simple Light Source/ Power Meters or more automated Optical Loss Test Sets can perform this function. This test ensures that the fiber link exhibits less loss than the maximum allowable loss budget for the immediate application. Most customers are familiar with Basic Certification - sometimes known as Tier 1 fiber certification – which measures attenuation (insertion loss), length and polarity.
These OTDR parameters will adjust the pulse width, averaging time, dead zones, and the distance range for your given fiber run to offer the most accurate results. For some tests, using the auto-test function may be enough to get you accurate results, but other may require you to manually set the OTDR testing parameters based on fiber cable length, type of cable, and complexity of your system. With so many different uses for OTDR testing, setting the correct OTDR parameters can ensure the tests you run and measurements you get are accurate. This is measured by recording the time it takes for signals to return to the OTDR. This returned scatter and reflections are measured to gather useful information about the cable, such as loss and distances to connectors or faults. Some of the light transmitted through the cable will scatter and some will be reflected and returned to the OTDR. The results are based on the reflected signal that returns to the same OTDR port. The process of running these tests requires the OTDR tool to input a light pulse into one end of a fiber cable. These tools can also test components along the cable path like connection points, bends, or splices to analyze the cable’s capability from start to finish. Hand-held OTDRs build a virtual image of the fiber optic cable to determine the condition and performance capability of the fiber cable. An Optical Time Domain Reflectometer (OTDR) is a device that tests the integrity of a fiber cable and is used for the building, certifying, maintaining, and troubleshooting fiber optic systems.