Troubleshooting; Alarms - ADC HiGain HLU-200 User Manual

Troubleshooting

T
ROUBLESHOOTING
Minor alarm and diagnostic messages routinely appear on the HLU-200
front-panel four-character display. This display automatically turns on when
power is initially applied to the HLU-200. To conserve power, the display
remains on for only 5 minutes if neither the MODE or SEL buttons are
pressed. The use of either button activates the four-character display and
restarts the 5-minute power-control timer.
A
LARMS
Only one alarm can be displayed at a time, so the highest priority alarm is
displayed if more than one alarm exists. The following table lists the alarms
ordered by priority.
Table 3. Minor alarm and diagnostic message displays.
Message Full Name
ALRM Loss of Sync Word
LOSW
ALRM RLOS Remote Loss of Signal
DS1 DS1 BPV errors
ALRM MAL1 Margin Alarm Loop1
or or
ALRM MAL2 Margin Alarm Loop2
H1ES or HDSL CRC Error
H2ES Channel 1 or Channel 2
(1) When both HDSL loops lose sync word (LOSW), a system alarm condition exists.
However, since the HLU enters a self test cycling mode, the front panel LED lights yellow
instead of red and the SELF TEST message displays instead of the ALRM message.
12
Description
(1)
One of the HDSL loops has lost synchronization.
Loss of the HRU DS1 input signal.
Indicates that the number of BPVs at the HLU or
HRU DS1 inputs have exceeded the 24-hour ES
threshold.
Indicates that the margin on HDSL Loop 1 or
Loop 2 has dropped below the threshold (1 to 15
dB) set by the user.
Indicates HDSL Loop 1 or Loop 2 has exceeded the
user-defined 24-hour ES CRC threshold.
October 4, 1999
350-200-111-02, Issue 2
HLU-200 List 1A