User Manual

ADCP-75-136 • Issue 1 • November 2002
Page 55
© 2002, ADC Telecommunications, Inc.
16173-B
Figure 31. Removing Fan From Grill
13. Place the DHU or DEU AC power On/Off switch in the ON position (press I).
14. Verify that the fans run properly following power up.
15. Notify the NOC or alarm monitoring system operator that the system is going back
online.
6.6 DHU or DEU Modular Optical Transceiver Replacement Procedure
The modular optical transceiver should be replaced when testing indicates that the transceiver
has failed. Use the following procedure to replace an optical transceiver in a DHU or DEU:
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 transceiver of any digital 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 transceiver or optical fiber connector
to avoid the potential of dangerous amounts of radiation exposure. This practice also prevents
dirt particles from entering the transceiver or connector.
1. Put on the IR filtering safety glasses.
2. Slip on an Electro-Static Discharge (ESD) wrist strap and connect the ground wire to an
earth ground source such as the grounding stud on the DHU or DEU front panel. Wear
the ESD wrist strap while completing the optical transceiver replacement procedure.
Warning: Electronic components can be damaged by static electrical discharge. To prevent
ESD damage, always wear an ESD wrist strap when handling electronic components.
3. Place the PORT ON/OFF switch for the optical transceiver being replaced in the OFF
position (press O).