Comtech EF Data SDM-2020 - Manual (Page 63)

SDM-2020 Satellite Modulator Revision 7
Front Panel Operation MN/SDM2020M.IOM
5-21
5.6.5.3 FAULTS/ALARMS:COMMON
COMMON
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Selections available include the following:
Fault/Alarm Possible Problem and Action
BATTERY/CLOCK M&C battery voltage or clock fault. Indicates a low voltage in the memory battery.
Typically will be active when a modulator has been Hard Reset, or the firmware has
been changed.
When a Hard Reset has been executed or the firmware has been changed, this fault
will typically be active when the modulator is first turned on.
It should automatically clear as the battery charges up.
-12 VOLT
SUPPLY -12V power supply fault. Indicates a high or low voltage condition. Level is ± 5%.
Check for a short on the -12V line from the power supply or on the board. Check TP2
on the M&C section to verify the proper -12V monitor voltage (1.06V).
If this voltage is not correct, it will verify that the -12V supply is not at the proper level.
This would indicate the power supply is faulted. Return modulator for repair.
+12 VOLT
SUPPLY +12V power supply fault. Use the same procedure as with -12V fault. To verify the
+12V power supply voltage, check TP4 on the M&C. A voltage of 3.81V will be
monitored when the +12V is at the proper level.
+5 VOLT SUPPLY +5V power supply fault. Use the same procedure as with -12V fault. To verify the +5V
power supply voltage, check TP5 on the M&C section. A voltage of 2.5V will be
monitored when the +5V is at the proper level.
CONTROLLER Controller fault. Indicates loss of power in the M&C card. Typically indicates the
controller has gone through a power on-off cycle.
1 Use the [ ←] [→] arrows to make a selection.
2 Press .