The Optical Time Domain Reflectometer (OTDR) is a test device for characterizing, maintaining and troubleshooting fiber optic networks. An OTDR testing measures the strength of return reflections in optical fibre by transmitting and analysing pulsed laser light traveling through an optical fibre. When the laser light is sent, a photodiode measures the returning light energy or optical power over time and converts it into an electrical value that is sampled, amplified, and graphically displayed on a screen. It provides detailed information about the optical link and the condition of passive optical components by indicating their location, associated power loss and fibre lengths.

How to properly perform an OTDR testing?

OTDR measurements provide information on the quality of the installed fibre system before it is put into service, to ensure that the network is functioning properly. It diagnoses the condition of an optical cable that would otherwise be impossible to see.

The accuracy and utility of an OTDR testing depends on several criteria:

- First, the ends of all fibres under test, launch cables, connectors, and adapters must be cleaned and inspected.

- Telecom technicians then need to set and adjust the correct parameters: measurement wavelengths, measurement mode (manual or automatic), range, laser pulse width, measurement accuracy, etc.

- Next, the information related to the fibre link must be filled in for the post-processing of the measurement results (e.g.: name and number of the fibre, its increment, etc.).

- Once the parameters have been set, telecom field engineers must check the compatibility of the connection of the link to be tested with the connection of the launch cable and the reflectometer.

- Then, technicians must run the OTDR for the necessary time to acquire the test results and “trace”.

In addition to reliable OTDRs, Telenco store provides technicians with fibre launch boxes, fibre inspection devices and fibre cleaners which are necessary equipment to ensure that all measurement tests are carried out as accurately as possible.