NT5D33 and NT5D34 Lineside E1 Interface cards Page 293 of 906Circuit Card Description and InstallationAn alarm condition is not automatically cleared until the system no longerdetects the respective bit error threshold during the corresponding durationperiod.For example, if AL1 threshold of 6 (representing 10-6) is specified, and aduration period of 100 seconds is specified, an alarm is activated if more than200 bit errors occur in any 100 second period. As soon as the alarm isactivated, the bit counter is reset to 0. If the next 100 seconds pass, and lessthan 200 bit errors are detected, then the alarm clears after the alarm’sduration period. However, if more than 200 bit errors are detected in the next100 seconds, the alarm condition continues for the designated time period.The alarm finally clears when the alarm condition is no longer detected forthe designated period, either by self-clearing (if this function is enabled), orwhen the Clear Alarm (C A) command is entered.In addition to bit errors, the Set Alarm function sets parameters for detectingframe-slip errors by establishing a threshold necessary to activate an alarm. Ifthe threshold value is exceeded, a level 2 alarm is activated. The frame slipthreshold can be specified from 1 to 255 frame slips per time period. Theduration time period can be specified from 1 to 24 hours.When entering the Set Alarm (S A) command, the MMI scrolls through thepreviously described series of alarm options. These options are displayedalong with their current value, at which point a new value can be entered orenter to retain the current value. Table 107 outlines the optionsavailable in the Set Alarm (S A) function.Table 107Set alarm options (Part 1 of 2)Option DescriptionAL1 Threshold Sets the allowable bit errors per second beforealarm level 1 is activated. Factory default is 6.AL1 Duration Sets the duration in seconds (from 1 to 3,600seconds) that alarm level 1 is activated. Factorydefault is 10 seconds.
