Comtech EF Data CRS-500, Installation And Operational Manual

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CRS-500 1:N Redundancy System
Revision 4
Cables and Connections 5–5 MN-CRS-500
5.2 CRS-500 Control Connections
5.2.1 Basic CRS-500 (CSU

DSU) Unit Connection
For 1:N redundancy configurations that do not require use of the optional CRS-280/280L IF
Switch Unit (ISU), use a CA-0000234 Control Cable (DB-25F to DB-25M, 8’) to connect the CSU
to the DSU. This is the basic setup for
all redundancy applications. Otherwise, refer to the next
section to make the Unit-to-Unit cable connections between the CRS-500 CSU, DSU, and
optional CRS-280/280L ISU.
5.2.2 Optional CRS-500 (CSU

DSU

ISU) Unit Connections
Make sure the power supply is disconnected before you connect any
cables. Serious injury or death could occur if the power supply is
connected while you connect any cables.
When a Tx IF ISU is not present, the CRS-500 will mute the offline
modem(s)’ Tx IF.
When the optional Comtech EF Data CRS-280/280L ISU is required, configured in either a
70/140 MHz (Figure 5-1) or L-Band (Figure 5-2), and make all cable connections as instructed in
this chapter section.
Do these steps:
1. Connect and secure the CA-0000234 Control Cable (DB-25F to DB-25M, 8’) between the
CRS-500 CSU and the DSU:
a. DB-25M connector labeled “P2 | Switch Control” on the CSU’s CRS-530 System
Controller, to
b. DB-25F connector on the rear panel of the DSU labeled “J1 | CSU/DSU
CONTROL”.
2. Interconnect the optional ISU. Connect and secure the CA-0021666 Control Cable (DB-
9F to DB-25M) between the CRS-500 DSU and the CRS-280/280L ISU.