Verilink QPRI 2921 (880-503143-001) Product Manual - Manual (Page 79)

Troubleshooting
Verilink QPRI 2921 4-5
Loss of
Frame
Alignment
(E1 Only)
This condition occurs when three consecutive in-error frame alignment
signals (words) are received, or when Bit 2 in a frame containing the non-
frame alignment signal (NFAS word) is received in error three consecutive
times.
The condition clears when the following events are satisfied:
• The frame alignment signal is detected in frame N.
• The non-frame alignment signal 1 is detected in frame N+1.
• The frame alignment signal is detected in frame N+ 2.
Loss-of-frame alignment (LOFA) after one continuous second causes a major
alarm and activates the relay contacts on the rear connector panel of the CIM.
This alarm activates the CFA if the LOFA is active from 2 to 45 seconds (as
defined by the user).
Frame
Alignment
Signal Error
Rate
(FASER) (E1
Only)
This alarm indicates that the FAS error rate exceeds a user-selectable
threshold of 10 -3 or 10 -6 for at least four seconds. This user-selectable alarm
can be designated as a major or minor alarm and activates the relay contacts
on the rear connector panel of the CIM.
This alarm activates the CFA if the FASER is active from 12 to 60 seconds (as
defined by the user).
Loss of
TS16
Multiframe
Alignment
(LOMA)
(E1 Only)
This condition occurs when the module cannot find the multiframe alignment
signal (MAS) pattern on TS16 when enabled for CAS signaling.
This alarm activates the CFA if the LOMA is active from 2 to 45 seconds (as
defined by the user).
Minor Alarms
Minor alarm fault conditions do not affect traffic along the network line. They
generate a minor alarm.
Alarm Type Description
Power
Supply
Missing
In redundant power supply configurations, this alarm indicates that one of
the redundant power supplies has failed or has been removed from the shelf.
Remote
Alarm
Indication
(RAI)
RAI. This alarm indicates that the remote end is in a state of alarm. A Remote
Alarm or Remote Alarm Indication is the alarm a receiving channel bank or
multiplexer sends to the other end of the circuit when it detects a Loss Of
Signal or Loss Of Frame. There is a 2- to 3-second integration period upon
detection of LOS or LOF before a Yellow Alarm is sent to the far-end
equipment. This condition is also referred to as a Yellow Alarm.
Bipolar
Violation
(BPV)
Threshold
A violation of the T1 bipolar AMI transmission pattern requiring successive
Ones (pulses) to be transmitted as pulses of opposite polarities. A BPV alarm
indicates transmission errors. However, B8ZS patterns contain intentional
BPVs that are not counted as errors.
Severely
Errored
Second
(SES)
15 min. Threshold/SES 24 hr. Threshold—An SES alarm is declared when 320
or more ESF error events occur within one second, or when an OOF (Out-Of-
Frame Second) occurs. An SES is a one-second period containing greater than
30% errored blocks (more than 1 errored bit) or at least one Severely
Disturbed Period (SDP).
Bit Error
Rate (BER)
Threshold
The Bit Error Rate is the ratio of the number of bit errors received to the total
number of bits transmitted in a given interval. The BER threshold indicates the
level above which a CSU alarm is generated and reported.
Alarm Classification/
Alarm Type Description