Method 3: Use Fiber-Optic Cable Test Equipment; Remote Device Fault Isolation - HP 27115A Installation Manual

Remote Device Fault
Isolation
Method 3: Use Fiber-Optic Cable Test Equipment
Another method to test the duplex cable is to test each fiber using special test
equipment (optical power source and meter). Refer to the "Cables, Test
Equipment, and Tools" section in chapter 1.
The operation of fiber-optic test equipment varies. The equipment may require
calibration. Consult the user manuals for your particular brand and models.
The basic test procedure is as follows:
1. Obtain a loopback cable like the one with part number
HFBR-3020.
2. Connect the optical power source to one end of the test cable, and the
optical meter to the other end. Use the optical meter to determine
optical power received.
3. Remove the test cable and go to the installed duplex cable.
4. Identify both ends of a single fiber in the duplex cable.
5. Connect the optical power source to one end of the fiber, and the
optical power meter to the other end.
6. Measure the optical power through the fiber. Compare this with the
power measured with the test cable. The difference must not exceed
6 dB. If it is greater, replace the duplex cable.
7.
If the loss is not excessive, repeat the process on the other fiber, starting
with step 5 above.
8.
If both fibers pass the test, the cable is not faulty. You should proceed
with testing the remote device.
To test the remote device, refer to the procedures provided in the applicable
device service manuals.
Troubleshooting and Diagnostics 3-13