User's Manual

Appendix I: Optical test Procedures
Optical Loss Testing
MA 2000 Installation and Configuration Guide 72
7. Disconnect connectors B and C. Connect the Cable Under Test (CUT)
between connector B and C as shown below.
Figure 7-3. Connecting CUT
8. Record Power Meter reading as Pcut in dBm units.
9. Calculate Cable Loss Ldut from the equation Lcut = P2- Pcut.
10. The maximum allowable loss should be < 0.5 dB/km for SM cables and <
0.5 dB for every mated pair of connectors.
7.2.3 Example
Testing a 50 meter cable with SC/APC connectors at each end.
• P1 = -1dBm
• P2 = -1.5dBm
• L12= P1 – P2 = -1dBm - (-1.5) = 0.5 dB
Conclusion: the test cables are of sufficient quality to continue testing.
• Pcut = -2dBm
• Lcut = P2 - Pcut= -1.5dBm - (-2dBm) = 0.5 dB
This is acceptable since a mated connector pair was added along with the CUT and a loss of
-0.5 dB is allowed for every mated pair of connectors.