Rockwell Automation 1786-series ControlNet Fiber Media Planning and Installation Guide - Manual (Page 56)

56 Rockwell Automation Publication CNET-IN001C-EN-P - October 2011
Chapter 5 Verify Your Network
Do not test the cable with the wrong power source because you will get inaccurate
readings. The power budgets are at the source wavelengths.
Verify each segment length by using an optical time domain reflectometer
(OTDR) field tester or by using the markings on the cable jacket.
See page 57 for more information.
Optical power meters transmit a light source at one end of your cable with an
optical power meter at the other end of the cable. You can read the attenuation or
power from the power meter to confirm the attenuation of your section.
See Table 5 on page 33 for module distance ratings.
Incorrect Loss Measurement Example
If you are testing a single-mode or multi-mode cable with a 640 nm light source,
you will get an incorrect loss measurement. You must test the fiber at 1300 nm to
match the cable rating.
Always record and maintain records for attenuation levels for each cable section
strand. The attenuation records are valuable tools for troubleshooting and
maintaining your network.
Table 9 - Fiber Operation Wavelengths
Module Wavelength
1786-RPFS 650 nm
1786-RPFM 1300 nm
1786-RPFRL/B
1786-RPFRXL/B
Power source
must match the
cable segment you
are testing.
Power Meter