Troubleshooting; System Alarms; Hdsl System Alarms - ADC HiGain HLU-432 User Manual

150-432-100-02, Revision 02
T
ROUBLESHOOTING
This section provides information about system alarms and loopback testing. In addition to these troubleshooting
aids, the Maintenance Terminal provisioning interface includes troubleshooting screens (see
Troubleshooting Screen" on page
S A
YSTEM LARMS
Table 12 lists possible HLU-432 alarm states and the corresponding front-panel messages. More than one alarm
condition can exist at any given time, but only one message can be displayed. For multiple alarms, only the highest
priority alarm displays.
Front-panel
Alarm State
Message
ALRM LOSW Loss of Sync
(a)
Word
ALRM LLOS Local Loss of Signal Loss of the DSX-1 input signal.
ALRM RLOS Remote Loss of
Signal
(b)
ALRM R(L)AIS Remote (or Local)
Alarm Indicating
Signal
ALRM MAL1 Margin Alarm
or Loop1
ALRM MAL2 or
Margin Alarm
Loop2
ALRM BER Bit Error Rate
exceeded
NONE No alarm
(a) When both HDSL loops lose sync word (LOSW), a system alarm condition exists. However, since the HLU-432 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.
(b) This message is reported in the Span Status screens, but not on the front-panel display.
HLU-432 List 1
36) that provide a basic graphical analysis of system problems.
Table 12. HDSL System Alarms
Description
One of the HDSL loops has lost
synchronization.
Loss of the HRU DS1 input signal.
Indicates an AIS pattern of all ones is being
transmitted (XMT) from the remote (or
local) T1 output port.
The margin on HDSL Loop 1 or Loop 2 has
dropped below the minimum threshold
value set by the terminal MARGIN ALARM
THRES.
The combined T1 and HDSL BER has
exceeded you set threshold limits of 10
- 7
or 10 .
No current alarm condition.
July 18, 2002
"View
To Inhibit:
Cannot be inhibited.
Cannot be inhibited.
Disable the RDA (Remote DS1 Alarm)
option. This prevents an LOS condition at
the DS1 input to a HRU from closing the
alarm contacts (pins 20 and 21 on the
card-edge connector). The front-panel
Status LED still flashes red and the ALRM
RLOS message displays to alert you of the
LOS state. LOS is sent towards the network
from the HLU. This option prevents the
common occurrences of a CPE LOS
condition from generating recurring alarms
and AIS payloads.
Set LBPK option to ENA or DIS.
Set the Margin Alarm Threshold option to 0
(zero).
Select NONE for the BER system option.
-6
Cannot be inhibited.

Troubleshooting

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