3Com 3C13840, Руководство по установке

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4-port Channelized T1/PRI FIC 4T1 (3C13870) and 4-port Fractional T1 FIC 4T1-F (3C13821) 69
Internal DIP Switch
Interface cables
1 Select the 4E1/E1 cable appropriate to the type of the port on the remote device,
and correctly set the DIP switches of the 4-port E1/CE1/PRI FIC/4-port Fractional E1
FIC.
■
If the impedance of the remote port is 75-ohm, select the E1 75-ohm
unbalanced coaxial cable and 75-ohm 4E1 adapter cable, and set all the DIP
switches on 4-port E1/CE1/PRI FIC/4-port Fractional E1 FIC to the ON position
(that is, the port impedance is 75-ohm).
■
If the impedance of the remote port is 120-ohm, select the E1 120-ohm
balanced twisted-pair cable and 120-ohm 4E1 adapter cable, and set all the
DIP switches on 4-port E1/CE1/PRI FIC/4-port Fractional E1 FIC to the OFF
position (that is, the port impedance is 120-ohm).
2 Insert the DB25 connector of the 4E1 adapter cable into the desired DB25 port
on 4-port E1/CE1/PRI FIC/4-port Fractional E1 FIC port and tighten the
thumbscrews.
3 Determine the sequence number of the DB15 connector at the other end of the
4E1 adapter cable, and connect the connector to the E1 cable.
4 Power on the Router, and check the status of the LINK LED on the card panel.
An OFF LED means that the line has failed and the signal has not been
synchronized. Check the line in this case.
4-port Channelized
T1/PRI FIC 4T1
(3C13870) and 4-port
Fractional T1 FIC 4T1-F
(3C13821)
4-port Channelized T1/PRI FIC
4-port Channelized T1/PRI FIC function to transmit, receive, and process T1 data
flows. In addition, they provide CT1 access, implementing the ISDN PRI function,
so that one board can serve multiple purposes.
4-port Fractional T1 FIC
4-port Fractional T1 FIC are fractional T1 (T1-F) cards. They are different from in
the sense that:
■
The time slots can only be bundled into one channel at the speed of nx64K or
56K, given n=1-24. However, a T1 card allows the arbitrary grouping of 24
channels and multiple bundling operations.
■
The FIC cards do not support PRI mode.
Interface Attributes
The following table describes the interface attributes of the FIC cards.
Table 8 Interface attributes of FICcards
Card
4-port
Channelized FIC
4-port Fractional
E1 FIC
DIP switch S2 S1 S2 S3 S4
The controlled E1
interface
Interface 1
Interface
0 Interface
1 Interface
2 Interface
3