PairGain PG-Flex, Manual

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PG-Flex System Overview
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The 23-inch COT Shelf (Figure 3), when fully populated, accommodates four complete systems.
Each system requires one COT line unit and up to three channel units.
Figure 3. Four 24-Channel PG-Flex Systems (23” Shelf)
Alarm Unit
PG-Flex supports two types of Alarm units, the FAU-728 List 1 and the FAU-728 List 2. Both
Alarm units provide PG-Flex Shelf interface to the CO Audio and Visual Alarms, and provide at
least one test jack for line breakout functions (Looking-In, Looking-Out, Bridging). Neither Alarm
Card supports the Pair Gain Test Controller (PGTC) test function.
FAU-728 List 1
The FAU-728 List 1 interfaces with the Central Office alarms and provides unique test jacks for up
to four installed COT line units within a single PG-Flex COT shelf. The FAU-728 does not operate
unless powered by a COT line unit in any slot position in an FCS-718 (19” shelf) or in the System
1 or 2 positions in an FCS-719 (23” shelf).
FAU-728 List 2
The FAU-728 List 2 Alarm Unit provides one test jack which is shared by all the COT line units
installed in the PG-Flex shelf. Additionally, the Alarm Unit serves as a Craft Port Multiplexer for
all COT line units installed in the shelf. Upon detection of the List 2 Alarm Unit, the Craft
Maintenance Port connectors on the individual line units are disabled and communications are
routed to the backplane.
The FAU-728 List 2 Alarm Unit can be used in situations where digital data service cards (ISDN,
DDS) are used in the shelf but the PGTC function is not required. The List 2 Alarm Card provides
an 8 kHz sync signal to all COT line units installed in the COT Shelf. The 8 kHz sync signal is
derived from the Central Office supplied Composite Clock. The Alarm Unit reports a loss of the
Composite Clock signal. The severity of the failure is user definable (Major, Minor, disabled).
The FAU-728 List 2 is powered from the CO battery independently of the COT line units.