SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
MCS--4200/7200 Multi--Channel SATCOM System
23--20--35
15 Jul 2006
Honeywell International Inc. Do not copy without express permission of Honeywell.
Page 6--11
5
The red LED also lights as long as the failure persists, if the HSU detects
any CM failure that has its own Level I code while continuous monitoring is
controlling the LEDs. Otherwise, both LEDs are turned off. Continuous
monitoring itself never causes the green LED to light. The presence or
absence of functional test failures does not affect the CM indication.
(d) HSU-SDU Communication
1
The HSU communicates its functional testing/CM failure status to the SDU
through the HSU status word. The HSU indicates a FW SSM state in its
status word, when failures are present that prevent it from offering HSD
service.
2
For certain failures detected during continuous monitoring, the appropriate
discrete failure bits and the SSM FW state are set within the maintenance
and status words as long as the failure persists.
(4) SDU Failure Reporting
(a) General
1
The SDU reports its functional testing/CM failure status and all other system
LRUs by:
•
Activating its alphanumeric display
•
Communicating to the SCDU, CMC, CFDS, and CMT interfaces.
2
The alphanumeric display indicates all applicable failure conditions with no
regard to:
•
Any type of internal/external failure differentiation
•
Any CFDS failure class distinctions
•
Which LRU detected a failure (either the SDU itself or one of the reporting
LRUs in the SATCOM subsystem).
3
The SDU delays reporting the results of the functional test sequence for a
period of 5 seconds. This gives continuous monitoring the opportunity to
perform its unique tests during the delay period, and include any current CM
failures in the test report. The SDU takes a snapshot at the end of the
functional test delay period to include all currently active CM failures in
addition to all failures detected during functional testing. The functional test
delay period applies to the SDU alphanumeric display, the SCDU
maintenance pages, the CFDS pages, and the CAIMS and CMC fault
summary words, but not to the CMT.
(b) SDU Front Panel Indicators and Controls
1
The SDU indicators and controls are given in Table 6-4.
