Comdial DXP Plus Series, Руководство пользователя

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Configuring The Services and Interface Boards
The DXP Plus extracts clocking information from the central office (CO) that supplies the ISDN–PRI lines, and
routes this information to the DXOPT–SYN card. The sync card uses this clocking information to derive the
synchronizing signal for the T1/PRI board’s transmit clock signal. Therefore, the T1/PRI board’s transmit clock is
slaved to the CO supplying the ISDN–PRI lines. If there is only one CO supplier, that source is the primary clock
source; however, if you are using two different suppliers, use the more reliable supplier as the primary source and
the other supplier as the secondary source.
You must designate one T1/PRI board as the primary board. Choose this board from among those boards that
interface the ISDN–PRI lines supplied by the primary CO supplier. Designate the primary board by placing straps
on the services board and by setting DIP switches on the expansion cabinet interface boards.
If your system has only one CO supplier, you do not need to designate a secondary board; however, if the system
has a second CO service supplier, you must designate one T1/PRI board as the secondary board. Choose this
board from among those boards that interface with the secondary CO supplier. Designate the secondary board by
placing straps on the services board or by setting DIP switches on the expansion cabinet interface boards.
If you designate primary and secondary boards to the system even though there is only one CO clock source, the
DXOPT–SYN card functions as though it is receiving two clock signals and lights both PRI and SEC LEDs on
the front edge of the card.
IMI89–255 Installing And Programming The DXPRI Card
12 – Configuring The Services and Interface Boards