User's Manual

ADCP-75-130 • Issue 3C • August 2006

Page 55

17282-A

OPTICAL LOOPBACK

CONNECTION DETAIL

OPTICAL

TRANSCEIVER

OPTICAL

LOOPBACK

Figure 27. DRU Loopback Test

21. The DRU STATUS LED or DEU HOST LED will turn either blinking red or green. If

the LED turns blinking red, the optical port is faulty and the optical transceiver must be

replaced. If the LED turns green, the optical port is good.

22. At the DHU or supporting DEU, place the PORT ON/OFF switch in the OFF position

(press O).

23. Remove the loopback from the DRU optical port or remote DEU host port.

24. Clean the optical fiber connectors and then reconnect the optical fibers to the DRU

optical port or remote DEU host port.

25. At the DHU or supporting DEU, place the PORT ON/OFF switch in the ON position

(press I).

26. Verify that the PORT OK/NOK LED turns green.

6.4.2 Optical Loss Test Procedure

A break in an optical fiber or a fault with the optical connector will interrupt communications

between linked components. Use the following procedure to isolate a problem with an optical

fiber or optical 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 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. At the DHU or supporting DEU, place the PORT ON/OFF switch for the optical fiber to

be tested in the OFF position (press O) if not already off.