Avaya Nortel Communication Server 1000 Reference page 229

The duration value is set in seconds and can be set from 1 to 3,600 seconds (1 hour). This
duration value indicates how long the alarm condition must last before an alarm is declared.
Low bit-error rates (10
than one second to detect an alarm condition above10
to shorter durations because the MMI error counter fills at 65,000 errors.
If the Set Clearing (S C) "Enable Self Clearing" option is set, the alarm indications (LEDs
and external alarm contacts) is automatically cleared after the specified period, or duration,
expires. Otherwise, the alarm continues until the command Clear Alarm (C A) is
entered.
When an alarm is cleared, all activity caused by the alarm indications is cleared:
• the external alarm hardware is deactivated (the contact normally open is reopened)
• the LED goes out
• an entry is made in the alarm log of the date and time the alarm was cleared
• carrier-fail line supervision ceases (for alarm level 2 only)
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 than 100 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.
Set alarm options
function.
Circuit Card Reference
7 9
through 10 ) are restricted to longer durations because it takes more
on page 230 outlines the options available in the Set Alarm (S A)
Man-Machine E1 maintenance interface software
6
. Higher bit-error rates are restricted
Table 98:
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