User's Manual

ADCP-75-158 • Issue 1 • July 2003 • Section 5: Maintenance

Page 5-13

5. Plug a 15 dB in-line optical attenuator into the PORT 1 optical port.

6. Connect a patch cord between the optical attenuator and the PORT 2 optical port.

7. Place the On/Off switch in the ON position (press I) and observe the PORT 1/PORT 2

LED indicator.

8. The PORT 1/PORT 2 LED indicator will turn either red or green. If the LED turns red,

either the PORT 1 optical transmitter or the PORT 2 receiver is faulty. If the LED turns

green, both PORT 1 and PORT 2 optical ports are good.

9. Place the On/Off switch in the OFF position (press O).

10. Remove the dust caps from the optical fiber connectors.

11. Clean each connector (follow connector supplier’s recommendations) and then insert each

connector into the appropriate optical port.

12. When ready to put the unit back into service, place the On/Off switch in the ON position

(press I).

13. Notify the NOC or alarm monitoring service that the system is going back online.

4.2.2 STM Loopback Test

1. Put on the IR filtering safety glasses.

2. Notify the NOC or alarm monitoring system operator that the system is going offline.

3. At the STM, place the On/Off switch in the OFF position (press O).

4. Disconnect the optical fiber connectors from the PORT 1 and PORT 2 optical ports and

place a dust cap over each connector.