| Anomaly
Type Definitions |
| Type |
Signature |
Interpretation |
Possible Cause |
Action |
Occurences
|
|
1
|
All telemetry including EPD_STAT
goes to zero |
Unknown |
HV Breakdown, producing EM noise
and other effects? |
Cautious MCP Operations in
following orbits |
14
|
|
2
|
EPD-STAT => 0, 3 anomalous HK
frames followed by all
HK TM =>0 across frame boundary. The anomalous HK frames are
identical repeat copies of the last good HK frame, including EPH_SCCT,
except EPD_FCNT and EPD_SPCT still increment. |
Science Processor stops, causing
Interface Processor
halt after 4 frames |
Sun reference pulse/spin segment
clock pulse
problems (tbc) |
Monitor and seek to diagnose |
115
|
|
3
|
EPD_STAT 106 |
DPU detects non-nominal
Sensor-DPU communication |
Spacecraft generated EM noise on
DPU-Sensor link? |
Monitor and seek to diagnose |
1
|
|
4
|
During turn on, EPD_STAT stalls
at value of 201 |
ZEPDBOOS command does not
execute during Turn On |
Unknown |
Modified turn on command
sequence used, send ZEPDBOOS twice
(on TC-1 after Orbit 116, first orbit of PP21) |
6
|
|
5
|
PEACE does not begin to turn on |
PPEAAON (28V power on) does not
execute during Turn
On |
DOMC report simultaneous with
ASPOC power on command |
Prevent simultaneous power on
commands via EPOS |
0
|
|
6
|
EPD-STAT => 0, 4 anomalous HK
frames followed by all
HK TM =>0 across frame boundary. In the anomalous HK frames, most
parameters including EPH_SCCT show 0, although a subset (including
EPH_SWP and EPH_STIM, and also EPD_P5VI and EPD_M8VI) are repeat copies
of the last good HK frame. Like Type 2, only EPD_FCNT and EPD_SPCT
still increment. In some cases, TMON = 0 in the last good frame,
suggesting a spin timing input error |
Science Processor stops, causing
Interface Processor
halt after 4 frames |
Sun reference pulse/spin segment
clock pulse
problems (tbc) |
Monitor and seek to diagnose |
73
|
|
7a |
EPD-STAT 109 for one frame, then
EPD-STAT 108 until turn
off |
Rephased sun pulse interval
longer than 5.15 sec
(EPD-STAT 109), causes a DPU-sensor communications problem (EPD-STAT
108) |
Sun pulse input to PEACE out of
Specification limits
(measured delay is > 5.15 sec, which is >> 4.4 sec)
|
Monitor and seek to diagnose sun
pulse problem (PDMS? S/C?) |
149
|
|
7b
|
As Type 7a, but in addition |
EPD-STAT 108 for many frames,
then EPD-STAT 106 until
turn off |
Either due to MCP commanding
once sensor is off, or
radiation? |
(tbc)
|
|
8
|
EPD-STAT 100 for many frames,
then EPD-STAT 201 until
turn off |
(tbc)
|
On ground tests with TC-2, this
signature is seen as
a response to power transients and (separately) as a response to
rephased sun pulse interval shorter than 2.0 sec |
Monitor and seek to diagnose sun
pulse or power system
problem (PDMS? S/C?) |
200
|
|
9
|
EPD-STAT 100 for many frames
then EPD-STAT 201 for one frame, after that EPD-STAT 202 until turn OFF
|
unknown
|
unknown |
Monitor and seek to diagnose |
1
|
|
10
|
EPD_STAT 201 after one frame of
100 after power on
sequence |
(tbc)
|
Unknown |
Monitor and seek to diagnose |
3
|
| Data Gap
|
|
|
|
|
(8) Not counted
|
| Total |
562
|
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