14
T400 User’s Guide
Conducting a Loop-Back AutoTest
NOTE:
The loop-back procedure calculates the average loss of two fibers and thus is not recommended
for fiber certification.
1 Set a Loop-Back AutoTest Reference. If this has already been done, skip to step 2.
2 Select an AutoTest rule.
3 Enter a file name.
4 Enter starting fiber names and numbers.
5 Connect to the two fibers under test to the Main Unit and the far-end test jumper (Figure 4-3)
NOTE:
Once the loop-back AutoTest reference has been set do not disconnect the test jumper from
the Main Unit transmit port (Tx2).
6 Conduct the test.
• Press the AUTO TEST key. The Main Unit will conduct the test and will display the results. Use
the ARROW keys to view the additional test result screens.
• Press SAVE (F3) to save the test results.
OR
• Press the AUTO TEST key again to retest the two fibers.
7 To test additional fibers reconnect the Main and the far-end test jumper to the next fiber pair then
repeat step 6. The fiber numbers will increment automatically.
fiber under test
Figure 4-3. AutoTest Setup
side 1
side 2
Rx1
Tx2
Main Unit
far-end test jumper
