MSID Problem Track page

• EPHIN

  • TEPHIN (EPHIN SENSOR HOUSING TEMP): red warning. Max: 308.07 on 12/24/02 (upper red limit: 303.0)
    - this is a closely followed situation this is an operational, not health and safety, limit. The effect on operational performance is still under investigation.
  • 5EPHINT (EPHIN TEMP): red warning. Max: 307.92 on 12/24/02 (upper red limit: 303.0)
    - a result of TEPHIN violation.
  • HKBBIASLEAKI (HK B bias leakage current): red warning. Max: 1.00 on 12/04/02 (upper red limit: 0.70)
    - this is temperature sensitive and a result of the first violation.
  • HKCBIASLEAKI (HK C bias leakage current): yellow warning. Max: 37.05 on 12/24/02 (upper yellow limit: 30.0)
    
  • HKDBIASLEAKI (HK D bias leakage current): red warning. Max: 42.62 on 12/24/02 (upper red limit: 40.0)
    
  • HKEBIASLEAKI (HK E bias leakage current): red warning. Max: 45.10 on 12/24/02 (upper red limit: 40.0)
    
  • HKEBOXTEMP (HK EBox temperature): yellow warning. Max: 312.60 on 12/24/02 (upper yellow limit: 308.0)
    

• HRMA

  • OOBTHR31 (RT 53: OBA AFT BULKHEAD): yellow warning. Max: 289.94 on 12/08/02 (upper yellow limit: 288.6)
    
  • OOBTHR56 (RT 158: TFTE AFT CYLINDER): yellow warning. Max: 289.55 on 12/11/02 (upper yellow limit: 288.6)
    
  • OOBTHR57 (RT 150: OBA AFT CONE ): yellow warning. Max: 289.46 on 12/08/02 (upper yellow limit: 288.6)
    
  
  These are on the outer mirror structure and not a serious concern.
  From Mark Freeman -
  My gut feeling is that we are OK on TFTE temperatures until they approach the HRMA temperature, so probably up to 65F should be fine (the reasoning being that we just need to retain cold-bias to the HRMA control temp.)

• ACIS

  • 1CRAT (COLD RADIATOR TEMP. A): yellow warning. Max: 154.8 on 12/25/02 (upper yellow limit: 148.16)
    - the cold radiator gets too warm during Earth passages seasonally.
  • 1CRBT (COLD RADIATOR TEMP. B): yellow warning. Max: 154.8 on 12/25/02 (upper yellow limit: 148.16)
    - the cold radiator gets too warm during Earth passages seasonally.
  • 1PIN1AT (PSMC TEMP 1A): yellow warning. Max: 305.06 on 12/08/02 (upper yellow limit: 303.16)
    -This was somewhat expected given the attitude, ACIS team is investigating the long term operational impact. first occurance 24 Sept 02 Day 267.
  • 1DPICACU (DPA INPUT CURRENT A): yellow warning. Min: 0.40 on 11/26/02 (lower yellow limit: 0.9)
    
  • 1DPICBCU (DPA INPUT CURRENT B): yellow warning. Min: 0.26 on 11/28/02 (lower yellow limit: 0.7)
    -This happens for 1 or 2 major frames when the DPA is power cycled before biases.
  • 1DPPWRA (DPA POWER A): yellow warning. Min: 11.82 on 11/26/02 (lower yellow limit: 18.2)
    
  • 1DPPWRB (DPA POWER B): yellow warning. Min: 7.61 on 11/26/02 (lower yellow limit: 18.2)
    -This is arithmetically related to the current underdraw.

• SIM

  • FAMTRTEMP (FA Motor Temperature): red warning. Max: 286.65 on 11/17/02 (upper red limit: 285.0)
    
  • BOXTEMP (SEA Box Temperature): yellow warning. Max: 293.65 on 11/17/02 (upper yellow limit: 292.0)
    
  From Mark Freeman -
  I think only insofar as they affect the instrument boxes, as we have seen recently with the PSMC. i think the SIM itelf, including the FA, are no problem at all.

• SPACECRAFT - Subsystems

  • 3TTHRC2T (TT AT HRC BIPOD ATTACH 2 ABORT HTR TSC2 TEMP): yellow warning. Max: 296.47 on 12/08/02 (upper yellow limit: 293.0)
    
  • TSCIUSF1 (SC-IUS FITTING-1 TEMP): red warning. Max: 359.12 on 12/08/02 (upper red limit: 349.7)
    
  • TSCIUSF8 (SC-IUS FITTING-8 TEMP): red warning. Max: 360.69 on 12/08/02 (upper red limit: 349.7)
    - these run warmer than the other 2 fittings and they have periodically warmed during the mission.
    
  • TFSSBKT1 (FSS BRACKET-1 TEMP (+Y)): yellow warning. Max: 341.84 on 12/24/02 (upper yellow limit: 333.0)
    - this is the result of a long term warming trend.
    
  • TFSSBKT2 (FSS BRACKET-1 TEMP (-Y)): yellow warning. Max: 340.27 on 12/24/02 (upper yellow limit: 333.0)
    - this is the result of a long term warming trend.
    
  • TMZP_CNT (-Z PNL TEMP:CENTER): yellow warning. Max: 333.98 on 12/24/02 (upper yellow limit: 327.4)
    - this is the result of a long term warming trend.
    
  • TMZLGABM (-Z LOW-GAIN ANTENNA BOOM TEMP): yellow warning. Max: 326.60 on 10/14/02 (upper yellow limit: 321.9)
    
  • TCYLAFT1 (CNT CYL TEMP:16-IN FWD OF SC-TS FIT-1): yellow warning. Max: 298.48 on 12/24/02 (upper yellow limit: 294.1)
    
  • TCYLAFT6 (CNT CYL TEMP:16-IN FWD OF SC-TS FIT-6): yellow warning. Max: 297.96 on 12/24/02 (upper yellow limit: 294.1)
    
  • TRSPMTPC (RAD SHR PNL TEMP:TTWN MUPS AND PCAD): yellow warning. Max: 295.00 on 11/09/02 (upper yellow limit: 294.1)
    
  • 3FAMYZAT (FA STRUCTURE +X FACE AT -Y-Z END ABORT HTR): yellow warning. Max: 308.14 on 12/08/02 (upper yellow limit: 308.0)
    
  • CSSR2CBV (#SSR-2 CONVERTER B VOLTAGE): red warning. Max: 4.96 on 12/25/02 (upper red limit: 1.0)
    
  From Mark Freeman -
  i think the first two are related to whatever mechanism we believe has produced the rise in the EPHIN and other -Z hardware temperatures (surface degradation?). i'm guessing the +Z antenna boom only gets illuminated by the sun at low pitch angles, otw it is always shaded. the recent ACIS PSMC yellow limit violation was due to an extended observation at ~48 degree pitch. i think a general trend toward longer observations is responsible for increasing the scatter envelope on many of the slow-to-respond temperatures.

• ACA

  • TEMPHOUS (temp 2 - AC housing): yellow warning. Max: 288.35 on 12/12/02 (upper yellow limit: 288.0)