Nortel Networks 1000 User Manual
Page 292
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NT5D33 and NT5D34 Lineside E1 Interface cards
If self-clearing alarm indications are disabled, carrier-fail line supervision
terminates when the alarm condition has ceased, but the external alarm
contact and faceplate LED remain active until the alarm is cleared.
A heavy bit-error rate can cause 200 bit errors to occur much more quickly
than100 seconds. This causes the alarm to be declared sooner.
An alarm condition is not automatically cleared until the system no longer
detects the respective bit error threshold during the corresponding duration
period.
For example, if AL1 threshold of 6 (representing 10-6) is specified, and a
duration period of 100 seconds is specified, an alarm is activated if more
than 200 bit errors occur in any 100 second period. As soon as the alarm
is activated, the bit counter is reset to 0. If the next 100 seconds pass,
and less than 200 bit errors are detected, then the alarm clears after the
alarm’s duration period. However, if more than 200 bit errors are detected
in the next 100 seconds, the alarm condition continues for the designated
time period.
The alarm finally clears when the alarm condition is no longer detected for
the designated period, either by self-clearing (if this function is enabled), or
when the
Clear Alarm (C A)
command is entered.
In addition to bit errors, the Set Alarm function sets parameters for
detecting frame-slip errors by establishing a threshold necessary to
activate an alarm. If the threshold value is exceeded, a level 2 alarm is
activated. The frame slip threshold can be specified from 1 to 255 frame
slips per time period. The duration time period can be specified from 1 to
24 hours.
When entering the
Set Alarm (S A)
command, the MMI scrolls through
the previously described series of alarm options. These options are
displayed along with their current value, at which point a new value can be
entered or enter
<CR>
to retain the current value.
outlines the options available in the
Set Alarm (S
A)
function.
Table 112
Set alarm options
Option
Description
AL1 Threshold
Sets the allowable bit errors per second before alarm level 1 is
activated. Factory default is 6.
AL1 Duration
Sets the duration in seconds (from 1 to 3,600 seconds) that
alarm level 1 is activated. Factory default is 10 seconds.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311
02.06
Standard
27 August 2008
Copyright © 2003-2008 Nortel Networks
.