1 rs-485 interface, 2 red auto/manual signal – Comtech EF Data CSAT-5060 User Manual
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C-Band Transceiver
Revision 1
Redundant Systems
MN/CSAT5060.IOM
5–7
5.2.1
RS-485 Interface
The RSU-5060 provides a single point interface for the customer’s M&C system by pig
tailing the 4-wire RS-485 input to J5 and passing it out on both the J1 and J3 interface
connectors. When using the RS-485, 4-wire interface to talk to the individual CSAT’s
are addressed at subsequent addresses through the use of the ‘B SELECT *’ signal going
to CSAT B on the J3 interface connector. To set or change the address of both units, use
the SPA=XXXX command defined in sections 3 and 4 in conjunction with the global
address 0000.
Example: To set the two CSAT’s to addresses 0064 and 0065 send the
following command: <0000/SPA=0064’cr’
5.2.2
RED AUTO/MANUAL Signal
Pin P on the J5 connector is the ‘RED AUTO/MANUAL’ input pin. The user can use this
signal to control the operating mode of the RSU-5060. If this pin is left open, the RSU-
5060 is operated in the AUTO mode. In AUTO mode, the RSU-5060 monitors the state
of CSAT A and CSAT B via the ‘A/B FAULT N.O.’ signals on the J1/J3 connectors. If
the ONLINE unit fails, the RSU-5060 will automatically command both the Tx and Rx
transfer switches to change position.
Note: If the OFFLINE unit also is FAULTED, no switchover will occur.
The ‘RED AUTO/MANUAL’ signal has a corresponding REMOTE COMMAND,
“RAM=X”. This command, defined in section 4, can be used to control the operating
mode of the RSU-5060 assuming that Pin P is left open. (Note: Grounding Pin P forces
the RSU-5060 into MANUAL mode independent of the “RAM=X” remote command.)