Comtech EF Data SDM-300A User Manual
Page 347
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SDM-300A Satellite Modem
Revision 6
Troubleshooting
MN/SDM300A.IOM
18–11
Table 18-2. SDM-300A Fault Tree (Continued)
TX I
F OUTPUT OFF
TX FAULT LED
TX FAULT RELAY
RX FAULT LED
RX FAULT RELAY
COM EQ FAULT LED
COM EQ FAULT RELAY
TX ALARM LED
TX ALARM RELAY #2
RX ALARM LED
RX ALARM RELAY #3
SPARE RELAY AL
ARM #1
PRIMARY ALARM RELAY
SECONDARY ALA
R
M RELAY
IBS BACKWARD ALARM
DEFFERED MAIN ALARM
TX AI
S
RX AIS
D&I TERR BWA
COMMON EQUIP FAULTS
(1)
(2)
(3)
(4)
(5)
(6)
**
***
(7)
**
***
**
***
(8)
*
*
**
***
*
**
***
***
BATTERY/CLOCK
X
X
X
-12V
POWER
SUPPLY
X X X
+12V
POWER
SUPPLY
X X X
+5V
SUPPLY
X X X
CONTROLLER
X X X X X
SELF TEST
X
INTERFACE
MODULE
X X X X X
BACKWARD ALARMS
(IDR OVERHEAD ONLY)
BW
ALARM
RX
#4
X X X
BW
ALARM
RX
#3
X X X
BW
ALARM
RX
#2
X X X
BW
ALARM
RX
#1
X X X
BW ALARM TX #4
X
X
BW ALARM TX #3
X
X
BW ALARM TX #2
X
X
BW ALARM TX #1
X
X
Legend
Test Note
Fault/Alarm Relay
Test Points Connector/Pins
(1)
TX FAULT
Pin 4 (NO), 5 (COM), 6 (NC) ****
(2)
RX FAULT
Pin 7 (NO), 8 (COM), 9 (NC) ****
(3)
COM EQ FAULT
Pin 1 (NO), 2 (COM), 3 (NC) ****
(4)
TX ALARM #2
Pin 4 (NO), 5 (COM), 6 (NC) ****
(5)
RX ALARM #3
Pin 7 (NO), 8 (COM), 9 (NC) ****
(6)
PRIMARY ALARM
Pin 43 (NO), 10 (COM), 27 (NC) ****
(7)
SECONDARY ALARM
Pin 44 (NO), 11 (COM), 28 (NC) ****
(8)
DEF MAINT ALARM
Pin 17 *****
*
IDR only.
**
IBS only.
***
D&I only.
****
A connection between the common and N.O. contacts indicate no fault/alarm.
*****
Signal is open collector high impedance if faulted.