COMPONENT MAINTENANCE MANUAL
AVIATION RECORDERS
FA2100CVR
Rev. 15 Page 63
Apr. 14/16
Description and Operation
23–70–04
Use or disclosure of information on this sheet is subject
to the restrictions on the cover page of this document.
Like any other internal CVR fault, this audio circuit failure will be reported using: the
Label 350 output Bit 11, the CVR Fault Status discrete output, and the Push
−
to
−
Test
results. If an audio input circuit failure occurs after a successful Push
−
to
−
Test oper-
ation, it will not be detected, or reported, until the next Push
−
to
−
Test is initiated.
This audio input circuit failure is the only fault that would not otherwise be detected
and reported by the CVR continuous BITE. Push
−
to
−
Test results are reported, dur-
ing the test, using the CVR Test Indicator output (Pins 15/16) which is usually con-
nected to an indicator lamp or meter on the CVR Control Unit. In addition, CVR fail-
ures reported through the Push
−
to
−
Test operation will be indicated by muting of the
CVR Monitor Audio output (Pins 5/6).
The fault criteria used to determine the reporting status associated with the CVR La-
bel 350 Status Word bits are summarized in Table 1.5.
Table 15. CVR Status Word Fault Reporting Criteria
L350
BIT
N°
FUNCTION
FAILURE CRITERIA
11
CVR Status (Audio Record-
ing Failure)
Any internal CVR failure that prevents correct record-
ing of the audio inputs (including CU failure and
Push
−
to
−
Test audio input circuit failure). May relent
depending on fault severity.
12
CMC Bus Status (OMS In-
put)
Loss of OMS input Heartbeat (valid Label 227 input)
for more than 3 seconds. Relents if OMS Heartbeat is
restored.
13
CVR Control Unit Failure
Loss of 18 VDC Control Unit supply voltage. Relents if
voltage level returns.
14
FDR Status (not used)
Always reported as “Failed” in CVR only recorder.
15
RIPS Fault Status (Pin 29)
RIPS Fault as reported on pin 29 input (if present).
16
CVR DataLink Recording
Failure
Any internal CVR failure that prevents correct record-
ing of the DataLink input.
17
Clock Status
Loss of the ARINC 429 GMT input (Label 125 or 150)
for more than 40 seconds. Relents if clock input is
restored.
18
Data Link Input Interface
Loss of the DataLink Heartbeat (valid Label 270) for
more than 3 seconds (only if DataLink Valid, Pin 56, is
asserted). Relents if DataLink Heartbeat is restored
or DataLink Valid removed.
Or
Presence of DataLink Heartbeat (valid Label 270) if
DataLink Valid, Pin 56, is not asserted. Relents if
DataLink Valid is asserted or DataLink Heartbeat is
removed.
The document reference is online, please check the correspondence between the online documentation and the printed version.