Tempo OPM510 Mode D'emploi page 20

Two Test Jumper Method: Link Loss (cont'd)
2. Connect a light source and optical power meter to the respective
patch panel ports using the test jumpers, as shown on the left.
3. Using the formula shown above, take the dBm reading on the
optical power meter (P3) and the nominal source output value,
corresponding to the light source in use.
Note: Make sure the optical power meter supports the wavelength
of the light source in use.
A
Source
4. It is advisable to measure the loss in both directions. Reverse
the source and optical power meter connections, as shown above.
Calculate the reverse loss using the formula shown above.
5. Report both forward and reverse loss values.
20
REVERSE LOSS (dB) = P2 – P4
Test
jumper 1
Cable
plant
Test
jumper 2
P4
Power meter
B