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Panasonic Digital Business System - Installation Manual
March 1997
Issue 5
19
Power Fail Telephone Connection
The DBS CCUs have a number of power fail telephone connection points. When a power failure occurs the first
few exchange lines are switched to the Power Fail Units (PFUs). 40% of incoming only lines and 20% of incoming
and outgoing lines must be supported in power fail mode. The DBS CCUs each have the following numbers of
power fail lines.
Table 6 - Power Fail Connections Per CCU
Connection of the PFUs is via DDK in the same way as analogue extensions. The DDK connections are located at
the left hand end of the CCU above the exchange line connection points. The highest lines are on DDK 1 and they
work downwards.
Figure 15 - Power Fail Connection (DBS 90 Shown)
System
No. Of PFUs
Lines Supported
DBS 38
3
1 - 3
DBS 68
4
1 - 4
DBS 90
5
1 - 5
DBS 128
8
1 - 5 CCU 1 / 1 - 3 CCU 2
DBS 158
9
1 - 5 CCU 1 / 1 - 4 CCU 2
DBS 180
10
1 - 5 CCU 1 / 1 - 5 CCU 2