AR 10006896, Operating And Service Manual

Page: 30 / 68

Model 500T2G8
18 Rev E
System Shutdown Screen - In the event of a system shutdown due to a latched fault (i. e., a fault such as body
overcurrent or power low line that requires a reset), the MENU screen is replaced by a screen indicating the
nature of the fault. Softkey S4 (labeled OK) is implemented as a reset key; pressing S4 brings back the
MENU screens. Line 3 of MENU 1, which normally displays the operational state of the TWTA, is used as a
fault display line until the fault is cleared. When the fault clears the system will automatically resume the
standby state and high voltage on will be enabled once again.
Factory Service Screens - A number of screens intended for factory service and calibration are behind
passwords and are not accessible to the user.
System Malfunction Screens - A number of screens are reserved to display error messages. These messages
are not normally seen and indicate a malfunction of the TWTA. System malfunction messages include the
following:
Database corrupt
Communication failure
Cannot restore
CU line voltage too low to operate. System shutdown
In the event that one of these appears, shut off the TWTA and contact an authorized service representative
before proceeding.
CAUTION:
Attempts to operate the TWTA despite control unit problems may result
in loss of the static RAM database and calibration information.