150-451-104-02, Revision 02
Installation
HDU-451 List 4
September 18, 1998
13
If the HDU-451 loses power, the HLU at the central is not present. Measure
the resistance of the HDSL input loop. Resistance should be normal loop
resistance plus the 25-Ohm signature of the HLU.
Line Unit Status Menu Messages
shows the messages that can appear on the line unit four-character
front panel display.
Table 5.
HLU-451 Status Menu Messages
Message
Full Name
Description
ALARMS
NONE
No Alarms
LLOS
Local Loss of Signal
No signal from local T1 interface.
RLOS
Remote Loss of Signal
No signal from remote T1 interface.
MNR
Minor Alarm
A Minor Alarm condition is in effect.
LOSW
Loss of Sync Word
One of the HDSL loops has lost synchronization.
H1ES
HDSL Loop 1 Errored
Second
Loop 1’s CRC has exceeded the user-selected
Errored Seconds threshold.
H2ES
HDSL Loop 2 Errored
Second
Loop 2’s CRC has exceeded the user-selected
Errored Seconds threshold.
DS1
Digital Service 1
DS1 input BPVs have exceeded the
user-selected Errored Seconds threshold.
ACO
Alarm Cut Off
An Alarm Cut Off is in effect.
LAIS
Local Alarm Indicating
Signal
Indicates an AIS (all 1s) pattern is being
transmitted from the local T1 output port.
RAIS
Remote AIS
Indicates an AIS (all 1s) pattern is being
transmitted from the local T1 output port.
HDSL-1(2)
HDSL Loop 1(2)
Defines HDSL loop 1(2) in any given span.
MAL 1(2)
Margin Alarm 1 (2)
The Margin on HDSL loop 1 (2) has dropped
below the threshold (1 to 15) set by the user.
