Comtech EF Data DMD-2050E - Manual (Page 170)

DMD2050E Univeral Satellite Modem Maintenance and Troubleshooting
MN-DMD2050E Revision 2 6–8
6.4 Alarm Masks
The DMD2050E self-monitors and isolates faults. Alarms for these faults are categorized as:

Active Alarms

Common Equipment Alarms

Backward Alarms
CAUTION
Masked alarms can cause unwanted effects in the performance of the unit.
You can mask certain alarms. Masking alarms can be helpful during debugging, or when you
need to to lock out a known failure.
When an alarm is masked, the front panel LEDs and the Fault Relays are not activated, but the
Alarm is shown in the display.
6.4.1 Active Alarms
6.4.1.1 Major Alarms
If a major alarm is on constantly, the modem has a hardware failure.
A major alarm flashes briefly during configuration changes and power-up. No action is
necessary.
Alarms are grouped into transmit and receive alarms. Transmit and receive alarms are completely
independent of each other.
6.4.1.2 Minor Alarms
Minor alarms show that a problem exists outside of the modem. Examples of such problems are:
• Loss of terrestrial clock
• Loss of terrestrial data activity
• Transmit or receive AIS condition