Alarm Option For Digital Loop Carrier Feed; Retiring System Alarms - ADC H2TU-C-202 User Manual

Testing
Front-Panel
Alarm
(a)
Message
(b)
xxx-MAL Margin Alarm
(b)
xxx-LA Loop Attenuation
ALRM
(a) The message, , displays prior to any alarm message.
(b) Message displays repeatedly as long as the alarm condition exists and is not included in the priority order.
(c) Only these alarms assert the System Alarm bus on pins 30 and 22 of the card-edge connector if the ALM option is enabled.
(d) When the HDSL2 loop loses sync word (LOSW), a system alarm condition exists. However, since the H2TU-C-202 List 2F
enters the acquiring mode, the front-panel status LED flashes red, and the ACQ or SIG message displays instead of the
ALRM
message.

Alarm Option for Digital Loop Carrier Feed

To improve HiGain HDSL2 compatibility with the switch-to-protect features used in Digital Loop Carrier (DLC)
feeder applications, the H2TU-C-202 List 2F has an Alarm Pattern (ALMP) option that allows you to select either
an AIS or LOS DS1 output payload for the following alarms:
•
LOSW on any loop
•
LOS DS1

Retiring System Alarms

To retire a system alarm, press the LBK pushbutton to execute an Alarm Cutoff (ACO). An ACO turns the alarm
off and replaces the ALRM message with an ACO message. The second part of the ALRM message, which defines
the cause of the alarm, remains. Both parts of the message remain until the alarm condition clears or another higher
priority alarm occurs.
50
Table 21. Front-Panel System Alarms Summary (Continued)
Description
The margin on the HDSL2 loop has dropped
below the minimum threshold value set for the
system. xxx denotes either TUC or TUR. If TUC
and TUR occur at the same time, then TUC
displays.
The attenuation on the HDSL2 loop has
exceeded the maximum value set for the HDSL2
loop attenuation threshold. xxx denotes either
TUC or TUR. If TUC and TUR occur at the same
time, then TUC displays.
October 25, 2002
LTPH-UM-1072-03
To Inhibit
Set the Margin Alarm
Threshold option to 0
(zero).
Set the HDSL2 Loop
Attenuation Threshold
option to zero.
H2TU-C-202 List 2F