5
If the optical loss is less than 5dB, connect the two ends of the optical cable to the APU and use the
tuning software to disable both processors. When configured in this manner, the APU will not alarm
when the fiber is shaken. The alarm relay will change states if the fiber is broken, cut, or unplugged. If
the IP port is being used, the processor will output a fault indicator via XML messaging when the cable
is disconnected or cut. Figure 3 below displays a screenshot from the FD322 Tuning Software
reflecting the proper parameters for cable break detector applications; observe that all the detection
related settings are disabled.
Figure 3
The cut and climb settings are disabled, so movement of the cable does not cause an alarm; only
cuts, breaks, or unplugging the connector will cause an alarm with these settings.
