User's Manual

ADCP-75-158 • Issue 1 • July 2003 • Section 5: Maintenance
Page 5-12
© 2003, ADC Telecommunications, Inc.
10. At the far end HU or STM, place the On/Off switch in the OFF position (press O).
11. Disconnect the optical power meter from the near end of the optical fiber.
12. Connect the optical power meter to the far end HU (Port 1) or STM (Port 2).
13. At the far end HU or STM, place the On/Off switch in the ON position (press I).
14. Measure the optical output power of the far end HU or STM. The power level of the
optical output signal from the HU or STM must meet the following specification:
HU Forward Path Output Signal (Port 1): 0 +
1 dBm
STM Reverse Path Output Signal (Port 2): +2 +
1 dBm
If the power level of the optical output signal is within specifications, the optical fiber is
faulty. If the power level of the optical signal is not within specifications, the far end
HU or STM optical transmitter is faulty.
15. At the far end HU or STM, place the On/Off switch in the OFF position (press O).
16. Disconnect the optical power meter from the far end HU or STM.
17. Reconnect the optical fibers at the HU and the STM.
18. Repeat steps 3 through 17 for each optical fiber that requires testing.
19. When ready to put the system back into service, place the On/Off switch in the ON
position (press I) at both the HU and STM.
20. Notify the NOC or alarm monitoring service that the system is going back online.
4.2 Optical Loopback Test
The following procedures provide tests to determine if an optical port fault exists with the Host
Unit or with the STM.
4.2.1 Host 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 HU, 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.
Danger: This equipment uses a Class 1 Laser according to FDA/CDRH rules. Laser radiation
can seriously damage the retina of the eye. Do not look into the ends of any optical fiber. Do not
look directly into the optical transmitter of any unit or exposure to laser radiation may result.
An optical power meter should be used to verify active fibers. A protective cap or hood MUST
be immediately placed over any radiating transmitter or optical fiber connector to avoid the
potential of dangerous amounts of radiation exposure. This practice also prevents dirt particles
from entering the connector.