The test of an optical power meter equipped with a stable light source is often called the insertion loss method. It reads the total end-to-end loss, which directly corresponds to whether the equipment can obtain sufficient optical power at the end. It and OTDR are not alternatives. The two conclusions must be able to confirm each other.

Reference lines must be set on site

First use a test jumper to directly connect the light source to the optical power meter, select the range and then reset to zero. This step is to set the reference line. Every time you change the test jumper or interface type thereafter, you must reset it to zero, otherwise the adapter's own insertion loss will be included in the link. The light source uses continuous light output, and the wavelength is consistent with the device under test: single-mode dual-fiber links are usually measured once at 1310 nm and 1550 nm, and the results of both levels must be entered in the table.

Positioning sequence when readings exceed budget

  • Check the end face first: dirt or scratches can cause the insertion loss to jump from 0.1 dB to more than 1 dB. Clean it and then measure again.
  • Replace segment by segment: Use short jumpers to replace segment by segment to determine whether the problem lies in the endpoint or the welding segment.
  • Compare device threshold: withSFP Gigabit single mode dual fiber 10KM optical moduleThe luminous power and the receive overload threshold are used to reverse the allowable loss of the link.
  • Test once in both directions, write the difference in the acceptance form, and leave no single conclusion.

and OTDR each have one section

The power method gives the total number, and the OTDR gives the distribution. If the total loss is qualified but the welding point reading of a certain core is abnormal, the point-by-point data of the OTDR shall still be used as the standard; when the OTDR misses a near-end event due to a blind zone, the power method shall be used to find out. Both sets of data are stored in the acceptance form at the same time, providing a more complete basis in case of disputes. EB-LINK technical support can help you calculate the threshold based on the link budget. Call 0755-83179002 on weekdays.

It is recommended to leave a 3 dB margin in design practice, taking into account the loss of optical fiber aging, subsequent reconnection and patch cord replacement. Passing the test is a true pass.