Nortel NT1R20 Description page 205

Figure 43
Display Configuration (D C) screen
LEI S/N 1103 Software Version 1.01
Alarms Enabled:
Alarm Level 1 threshold value:
seconds): 10
Alarm Level 2 threshold value:
seconds): 1
Frame slips alarm level threshold:
2
Current dip switch S1 settings (S1..S8)
Current dip switch S2 settings (S1..S8)
Alarm operation and reporting
NT5D33 and NTRB34 Line-side E1 Interface Cards
YES Self Clearing Enabled:
E-7
E-5
The MMI monitors the E1 link according to parameters established through
the Set Alarm command for the following conditions:
— Excessive bit error rate
— Frame slip errors
— Out of frame condition
— Loss of signal condition
— Blue alarm (AIS) condition
Descriptions of the excessive bit error rate and frame slip errors conditions
can be found in "Configuring parameters" on page 170. Bit errors may
activate either a level 1 or level 2 alarm. The remaining conditions, when
detected, will always cause the system to activate a level 2 alarm.
An out-of-frame condition will be declared if 3 consecutive frame bits are in
error. If this condition occurs, the hardware will immediately attempt to
reframe. During the reframe time, the E1 link will be declared out-of-frame,
and silence will be sent on all receive timeslots.
A loss of signal condition is declared if a full frame (255 bits) of consecutive
zeros have been detected at the receive inputs. If this condition occurs, the E1
link will automatically attempt to resynchronize with the distant end. If this
condition occurs for more than two seconds, a level 2 alarm will be declared,
and silence will be sent on all receive timeslots. The alarm will be cleared if,
after two seconds, neither a loss of signal, out-of-frame condition, nor blue
alarm condition occurs.
3/03/95 1:50
YES
Threshold duration (in
Threshold duration (in
5 Threshold duration (in hours)
On Off Off On Off Off Off On
On Off On Off Off Off On Off
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