Comtech EF Data CRS-300 - Manual (Page 160)

CRS-300 1:10 Redundancy Switch MN/CRS300.IOM
Cables and Connections Revision 19
4–86
4.11 CDM-600/L Modem Connections
If adding a modem to an operating 1:N system, care needs to be taken not to interfere with the
existing traffic. The cabling and power-up sequence must be correct to avoid contention in the
system from the modem Tx carrier. This sequence is described in Sect. 6.2.2.5 CONFIG: ACTIVE
(Activate Modems).
Traffic modems with differing data types can all be supported by the Redundant
Modem.
4.11.1 Control and Data Connections – CRS-300 to Modems
See Sect. 1.4.3.3 Modem Interface Cards for detailed information on the Switch RMI
and TMI cards available for use with the CDM-600/L modems.
The 25-pin Control/Data Cable CA/WR0066 provides the EIA-422/-232/LVDS traffic data path
and serial communication path between the Switch and the modems. Therefore, you must
alwys use this cable, even when the data type is G.703.
The Switch TMIs feature jumpers that are pre-set to ensure proper operation with
the following traffic data:
• For EIA-422 RTS/CTS, DTR/DSR signals using the CRS-340
• For HSSI with CA/TA signals using the CRS-370
See Chapter 5. MODEM, TMI, AND SWITCH CONFIGURATION for this important
configuration information.
See Figure 4-36 and do these steps to connect and secure the CA/WR0066 cables between the
Switch and each CDM-600/L:
• DB-25M connector labeled “P1” on the Switch RMI or TMI(s), to
• DB-25F connector labeled “P3B Data Interface” on the CDM-600/Ls.
If G.703 is the traffic data type, also do these steps to connect the CA/WR9038-6 data cable,
which you must use for either Balanced or Unbalanced G.703 Data:
• DB-15M connector labeled “P2” on the Switch RMI or TMI(s), to
• DB-15F connectors labeled “P7 Balanced G.703” on the CDM-600/Ls.