ADC 150-2248-01, User Manual

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Installation 150-432-100-02, Revision 02
8 July 18, 2002 HLU-432 List 1
V
ERIFICATION
Once the HLU-432 is installed, verify that it is operating properly. To do this, you need to monitor the following:
• Status LED
• Status messages reported by the front-panel display (see Table 2 on page 5 )
Verification without a Downstream Device
If there is no downstream device installed:
1 Verify that the HLU powers up. The front-panel display illuminates and reports four-character status
messages. (See
Table 2 on page 5 for a list of messages.)
2 Verify that the HLU attempts to communicate with downstream devices. Even if a downstream device is not
present, the following events should occur:
a The front-panel display reports four-character status messages.
b The HLU enters self-test mode (Status LED is yellow).
c The HLU again attempts communication with downstream devices, repeating events a through b until a
downstream device is detected.
Verification with a Downstream Device
If a downstream device has been installed:
1 Verify the HLU powers up. (The front-panel display illuminates and reports status messages.)
2 Verify the HLU attempts to communicate with downstream devices (status LED flashes green). One of the
following occurs:
• If downstream devices are successfully identified and the HDSL loops synchronize, the HLU status LED
will be a steady green. The HLU reports normal margin messages on the front-panel display.
• If downstream devices are not successfully identified, the HLU reports four-character status messages
and enters self-test mode. The HLU successively:
a enters self-test mode
b completes self-test mode
c attempts communication again
d reports four-character status messages.
The HLU repeats this cycle until a downstream device is detected.
3 If there is more than one span, verify that each subsequent span synchronizes normally by monitoring the
front-panel display messages.
4 If a remote unit is installed, verify that the last span synchronizes normally. The HLU status LED should be
a steady green, and the front-panel display reports normal margin messages.
5 Verify that a valid T1 signal has been applied to the HLU and the HRU.
• If no T1 signal is being applied to either the HLU or the HRU inputs, then the appropriate T1 alarms
(LLOS or RLOS) are observed on the front-panel display and the status LED flashes red.
• If a valid T1 signal is being supplied to the HLU and HRU, then T1 alarm indications should be absent
and the status LED should be a steady green.