What is an OTDR trace?

OTDR trace is a . sor, . trc, or other format file containing a graph with the data about the measured duct. Attenuation is a characteristic showing how much power (dB or dBm) is lost at a given location (attenuation at splice, cross) or in a given section of the duct.

How do you analyze OTDR trace?

First place one of the markers or cursors (usually called 1 or A on your OTDR) just before the reflectance peak. Next, place the second marker (referred to as 2 or B on your OTDR) just after the reflectance peak. The OTDR will calculate the loss between the two markers.

What is an OTDR used for?

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.

How do you use an OTDR machine?

Test Procedure

  1. Turn on OTDR and allow time to warm-up.
  2. Clean all connectors and mating adapters.
  3. Attach launch cable to OTDR. Attach receive cable (if used) to far end of cable.
  4. Set up test parameters on OTDR.
  5. Attach cable to test to end of launch cable. Attach receive cable (if used) to far end of cable.
  6. Acquire trace.

How does OTDR testing work?

OTDR injects a series of optical pulses into the fiber under test. It also extracts, from the same end of the fiber,light that is scattered or reflected back from points along the fiber. The strength of the return pulses is measured and integrated as a function of time, and is plotted as a function of fiber length.

How does OTDR measure distance?

The OTDR measures distance to the event and loss at an event – a connector or splice – between the two markers. To measure splice loss, move the two markers close to the splice to be measured, having each about the same distance from the center of the splice.

What is dB in OTDR?

Whenever tests are performed on fiber optic networks, the results are displayed on a power meter, OLTS or OTDR readout in units of “dB.” Optical loss is measured in “dB” which is a relative measurement, while absolute optical power is measured in “dBm,” which is dB relative to 1mw optical power Loss is a negative …

What is OTDR measurement?

The OTDR measures distance and loss between the two markers. This can be used for measuring loss of a length of fiber, where the OTDR will calculate the attenuation coefficient of the fiber, or the loss of a connector or splice.

How to interpret the OTDR trace?

If there is a reflective fault (mechanical connection, break, fiber end), then the OTDR trace indicates in this place a powerful reflection, much higher than the light coming from Rayleigh scattering, and we see a peak on the graph.

Is OTDR viewer software free?

Some OTDR viewer software packages are available free of charge usually with limited functionality. More sophisticated packages with comprehensive reporting and analysis functions will cost. OTDR software cannot magically compensate for poor OTDR data acquisition!

What can an OTDR do for You?

As opposed to the simple light source and power meter test method, the OTDR can identify and locate any potential faults, macrobends or breaks that could impact network performance. Dynamic range: The maximum optical loss an OTDR can analyze from the backscattering level at the OTDR port down to a specific noise level.

How do you measure the power output of an OTDR?

The most reliable way is to measure it with testers, or with a tester + OTDR with a tester function. Turn on the “transmitter” mode on one tester, and the “receiver” mode on the other.