Excalibur ISX 5312, Руководство по эксплуатации

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Excalibur ISX 5312/5314 T-1 Multiplexer Installation and Operation
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ES Alarm
An Errored Second (ES) is any second in which one or more ESF error events occur. An
ESF error event is defined as a CRC6 error event (when the CRC6 field calculated by the
customer equipment does not agree with the CRC6 field contained in the DS1 signal
received from the network), an OOF event, or a Controlled Slip event. The ISX
5312/5314 generates an ES alarm when it detects one or more ESF error events in a
1-second interval. The alarm is cleared when no ESF error events occur in a 1-second
interval.
BPV Alarm
The ISX 5312/5314 declares a BPV alarm when it detects a bipolar violation. The alarm
is cleared when the unit no longer detects any bipolar violations.
LOS Alarm
When the ISX 5312/5314 detects a loss of signal, it generates a LOS alarm and transmits
a Blue alarm, provided a Yellow alarm is not already being transmitted, to the far end via
the outgoing bit stream. In a daisy-chained configuration, when the master generates an
LOS alarm, it transmits a Blue alarm to the daisy-chained slave(s).
Reference Clock Changed Alarm
The ISX 5312/5314 generates a Reference Clock Changed alarm when it detects the
primary Transmit Clock Reference has failed and the unit has internally changed its
clock source to one in the user-selectable priority fallback clock list. When a higher
priority timing reference has recovered for 20 seconds, the unit automatically switches
back to that higher priority clock reference, provided the Clock Tolerance parameter is
set to Disabled.
DTE Failed Alarm
The ISX 5312/5314 generates a DTE Failed alarm when the specified DTE interface (1-
4) has an invalid signal level. The DTE Request-to-Send signal is monitored to
determine if an alarm condition exists.