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Alarm Definitions
Other Alarms
C-4
SpectraComm 553 Fractional T1 DSU
076R155-000
Installation and Operation Manual
Issue 7
Unit Failure
A Unit Failure alarm indicates that the DSU has not passed its Power On Self Test.
Unsolicited Test
An Unsolicited Test alarm event occurs any time the DSU enters a test mode that is not command-
ed by an SNMP controller. The DSU generates this alarm when it is commanded to perform a test
by a control lead in its DTE interface, an in-band loop code (Remote Test or Remote Digital
Loopback), or a front panel test switch.
Power Up
A Power Up alarm event occurs each time power to the DSU is turned off and then back on. It also
occurs when there is a system reset.
Configuration Change
A Configuration Change (Config Change) alarm event occurs each time there is a change to the
DSU configuration.
Top Supply Fail
A Top Power Supply Failure (Top Supply Fail) alarm event occurs when the DSU is installed in a
SpectraComm 2000 enclosure and the power supply installed in the upper position fails.
Bottom Supply Fail
A Bottom Power Supply Failure (Bottom Supply Fail) alarm event occurs when the DSU is in-
stalled in a SpectraComm 2000 enclosure and the power supply installed in the lower position fails.
Remote Not Responding
A Remote Not Responding alarm event is reported by a master SC 553 DSU when its remote SC
553 DSU does not respond to a wake up signal or to polling. The master DSU continuously polls
its remote, independent of the SCM.
Redundant Mode
A Redundant Mode alarm event occurs when an SC 553 DSU with the cascade port option in-stalled
and the redundancy feature enabled reroutes channel data from the primary T1 interface to the
redundant T1 interface.