TC Communications TC1903, User Manual

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MNL-19030-01-19
The RJ-11 cable connectors are frequently the source of various problems. Check out the connectors, cable,
and pin connections first. Once installation of the TC1903s is complete, it is a good idea to perform a bench
test to verify that the TC1903s are working properly.
If no LEDs are lit on the unit, check the DC power supply, terminal block connector plug, and/or power
source. If the problem persists, contact the Technical Support Department at TC Communications, Inc.
When there is an alarm condition, the red alarm "ALM" LED will be lit and the "OPT" & "SYNC" LEDs will
also flash to indicate the optic signal has been lost. The Alarm will also trigger the dry contact relay switch.
Future release.
Future release
Conventionally, fiber optic cable with yellow-colored insulation is used for single mode applications; gray or
orange-colored insulated cable is for multimode use. If multimode cable is used in a single mode application,
the test results could be erroneous and confusing.
The fiber optic link and/or the connectors are frequently the source of communication problems. If problems
are present, check the optic connectors and the integrity of the link first. Ideally, the link should be calibrated
for total loss after the installation has been completed. This will accomplish two things: (1) it will verify that
the total loss of the link is within the loss budget of the device and (2) it will provide a benchmark for future
testing. For example, a system that has been tested as having 6dB of signal loss when installed should not
suddenly test out as having a loss of 10dB. If this were the case, however, the fiber link or connector would
probably be the source of the problem.