EPHIN +27V-rail Supply Current-Limit Episodes

At elevated temperatures the +27V rail-voltage feeding the EPHIN HV power supplies undergoes current-limited behavior and its output voltage drops. The lowered +27V output results in a measured drop in the output of the HV power supply for detector G (as shown in the plot below) and presumably in the output of the HV supplies for the other detectors.

Detector G HV supply ouput vs the +27V-rail voltage

There is hysteresis in the system that requires a lower temperature than that at on-set for recovery from the current-limited condition. The table below lists the relevant IEPHIN temperatures at the on-set and recovery for each current limited episode to date.

Episode Start Time 5EPHINT at start TEPHIN at start 5EIOT at start TEIO at start Electonics Box at start Stop Time 5EPHINT at stop TEPHIN at stop 5EIOT at stop TEIO at stop Electonics Box at stop
2003-11-18 185539521.497 38.60 39.10 76.23 50.27 43.42 185762167.907 29.23 27.91 46.54 13.18 34.80
2003-11-23 185966971.115 38.60 39.10 77.73 51.33 43.42 186326065.531 28.80 27.40 46.54 13.18 34.31
2004-03-26 196667905.983 37.75 38.41 77.73 51.33 42.25 196687061.183 29.23 27.40 43.99 11.98 34.80
2004-08-25 209820706.564 37.75 38.41 79.23 53.45 42.25 209861903.366 29.65 28.43 47.82 15.18 34.80
2004-09-20 212068031.465 37.32 38.41 79.23 53.45 42.25 212163282.669 27.95 26.36 48.46 14.78 34.31
2004-10-28 215329663.611 37.75 38.41 79.23 53.45 42.25 215462831.617 28.80 26.88 43.35 9.58 34.80
2004-11-08 216285586.853 37.32 38.41 79.23 53.45 42.25 216384642.858 29.23 27.40 41.67 8.38 34.31
2004-12-22 220111247.825 37.75 38.41 79.23 53.45 42.25 220259241.432 28.80 27.91 49.73 17.34 34.31
2004-12-25 220336518.236 37.75 38.41 79.23 53.45 42.25 220474015.842 28.80 27.40 45.27 12.38 34.31
2005-04-07 229219414.637 38.17 39.10 77.73 51.33 42.25 229287507.440 30.08 28.43 42.71 9.98 34.80
2005-05-20 232997450.009 36.89 38.41 79.23 53.45 42.25 233059901.212 29.65 28.43 45.90 14.38 34.31
2005-07-01 236566221.372 38.17 38.41 76.23 50.27 42.25 236814320.583 29.65 28.94 49.73 17.79 34.31
2005-07-04 236875984.586 37.75 38.41 77.73 51.33 42.25 236938304.589 29.65 28.43 45.90 12.78 34.80
2005-07-06 237018598.993 37.75 38.41 77.73 50.27 42.25 237151898.199 29.23 28.43 51.33 18.24 34.31
2005-07-11 237461005.413 38.17 39.10 77.73 52.39 42.25 237501546.215 29.65 28.43 47.82 14.78 34.31
2005-08-15 240457351.150 37.75 38.41 79.23 53.45 42.25 240603507.957 29.23 28.43 48.46 16.89 33.83
2005-10-31 247124017.057 38.17 39.10 77.73 52.39 42.25 247319505.066 29.23 28.43 47.18 14.78 34.31
2005-11-02 247356241.067 38.17 39.10 77.73 52.39 42.25 247476026.673 29.65 28.94 47.18 15.18 34.31
2005-11-28 249559351.569 38.17 39.10 76.23 51.33 42.25 249765335.579 29.65 28.94 45.27 13.18 34.80
2005-12-05 250147652.396 37.32 38.41 81.53 55.57 41.68 250445082.810 29.65 28.94 45.90 13.58 34.80
2005-12-08 250473028.411 37.32 38.41 81.53 55.57 41.68 250904414.031 29.65 28.94 45.90 13.58 34.31
2005-12-19 251392740.454 36.89 38.41 81.53 55.57 41.68 251583505.263 29.65 28.94 44.62 13.58 34.31
2005-12-22 251628900.465 36.89 38.41 81.53 55.57 41.68 252530506.907 29.65 28.94 45.90 13.58 34.31
2006-01-02 252608833.310 36.47 37.71 81.53 55.57 41.68 253185194.937 27.95 27.40 51.33 20.04 33.83
2006-01-09 253211697.338 37.32 38.41 81.53 56.63 41.68 253409940.547 27.10 25.33 47.82 15.18 33.83
2006-01-12 253485511.751 37.75 38.41 79.23 54.51 41.68 253623927.757 29.65 28.94 45.27 13.58 34.31
2006-01-15 253686903.760 37.32 38.41 81.53 55.57 41.68 254097560.779 29.65 28.94 44.63 12.38 34.31
2006-01-21 254259854.187 39.02 39.80 77.73 52.39 44.02 254327946.990 29.65 28.94 44.63 11.98 34.31
2006-01-22 254359303.791 36.89 38.41 81.53 55.57 41.68 254807220.612 29.65 28.94 45.90 14.38 34.31
2006-01-28 254836609.414 36.89 38.41 81.53 55.57 41.68 255019633.422 29.65 28.94 44.63 12.78 34.31
2006-01-30 255042462.223 36.89 38.41 81.53 55.57 41.68 255465713.443 29.65 28.94 43.99 11.98 34.31
2006-02-05 255500087.844 37.32 38.41 79.23 54.51 41.68 257753185.549 29.65 28.94 45.27 12.78 34.31
2006-03-03 257797006.351 36.47 37.71 81.53 55.57 41.11 258314065.575 29.65 28.43 45.90 13.18 34.31
2006-03-10 258356311.977 37.32 38.41 79.23 53.45 41.68 258924276.803 29.65 28.94 45.90 13.98 34.31
2006-03-19 259156500.814 36.47 37.71 81.53 55.57 41.11 260030161.655 29.23 28.43 47.18 15.58 33.83
2006-03-30 260074244.857 36.47 37.71 81.53 55.57 41.11 260732606.488 29.23 28.43 47.82 15.98 34.31
2006-04-07 260759108.889 38.17 38.41 76.23 50.27 42.25 261416027.319 29.65 28.43 45.27 12.78 34.31
2006-04-14 261443054.521 36.89 37.71 81.53 55.57 41.11 261642084.930 29.65 28.43 45.27 12.78 34.31
2006-04-17 261668456.131 37.75 38.41 77.73 52.39 41.68 261863812.940 29.65 28.94 45.90 13.58 34.31
2006-04-20 261895169.742 37.75 38.41 77.73 52.39 41.68 262556942.573 29.65 28.43 45.27 12.78 34.31
2006-04-30 262823016.185 36.47 37.71 81.53 55.57 41.11 263433358.614 29.65 28.43 46.54 13.58 34.31
2006-05-09 263530971.418 36.47 37.71 79.23 54.51 41.11 263682769.825 29.65 28.43 44.63 12.38 34.31
2006-05-14 264001454.640 39.45 39.80 77.73 52.39 44.02 264172277.048 29.23 28.43 47.82 15.18 34.31
2006-05-24 264869080.281 37.32 38.41 79.23 53.45 41.68 264933893.084 29.23 28.43 48.46 15.98 34.31
2006-05-28 265209806.696 39.88 40.49 77.73 52.39 44.63 265282491.500 29.65 28.43 43.99 11.98 33.83
2006-05-31 265456856.308 38.60 39.10 77.73 52.39 43.42 265520094.711 29.65 28.43 45.90 13.58 34.31
2006-06-01 265563128.313 36.47 37.71 81.53 55.57 41.11 265752449.922 29.65 28.43 45.90 12.78 34.31
2006-06-05 265914613.129 37.32 38.41 79.23 54.51 41.68 266194462.742 29.23 28.43 47.18 15.18 33.83
2006-06-12 266460798.755 36.89 38.41 79.23 54.51 41.68 266983499.579 29.23 28.43 49.09 16.89 34.31
2006-06-20 267159307.588 37.32 38.41 79.23 53.45 41.68 267354664.397 29.23 28.43 47.82 15.58 34.31
2006-06-22 267383659.598 37.32 38.41 79.23 53.45 41.68 268256402.039 29.65 28.43 45.27 13.18 33.83
2006-07-04 268438507.647 36.89 38.41 81.53 55.57 41.68 269180181.282 29.23 28.43 48.46 16.43 33.83
2006-07-24 270097400.525 37.75 38.41 77.73 52.39 41.68 271234642.179 29.65 28.43 45.27 12.38 34.31
2006-08-06 271270197.380 38.17 38.41 77.73 51.33 42.25 273745416.696 29.65 28.43 43.99 11.98 33.83
2006-09-04 273778610.298 37.75 38.41 77.73 52.39 41.68 273977378.307 29.65 28.94 44.63 13.18 33.83
2006-09-07 274005586.309 37.75 38.41 79.23 53.45 41.68 275117768.761 29.65 28.43 44.63 11.98 33.83
2006-09-20 275148207.162 37.75 38.41 77.73 51.33 41.68 276026197.604 29.65 28.43 44.63 13.18 33.83
2006-10-01 276093765.607 36.04 37.71 81.53 55.57 41.11 276467685.624 29.65 28.43 42.19 9.58 34.80
2006-10-06 276513343.227 38.17 39.10 76.23 50.27 42.25 280175791.399 29.65 28.43 45.90 13.58 34.31
2006-11-21 280518748.216 36.89 38.41 81.53 56.63 41.11 281935970.683 29.65 28.94 43.99 11.98 33.83
2006-12-10 282138018.692 36.47 37.71 81.53 56.63 41.11 282602466.714 29.65 28.94 44.63 12.78 34.31
2006-12-16 282680924.318 38.17 38.41 76.23 51.33 41.68 296590880.179 29.65 28.43 43.99 11.58 33.83
2007-05-27 296620400.181 36.89 37.71 81.53 56.63 41.11 297535782.624 29.23 28.43 46.54 13.18 34.31
2007-06-07 297617651.428 36.89 37.71 79.23 54.51 41.11 299534745.920 27.95 27.91 54.53 22.75 32.87
2007-06-30 299595229.123 36.89 37.71 81.53 56.63 41.11 299988173.142 26.25 25.33 52.93 23.78 32.39
2007-07-05 300050099.545 36.89 37.71 81.53 55.57 41.11





The following links go to pages with plots of EPHIN performance during the episode.

Last modified: Fri Jul 6 09:57:00 EDT 2007

Dr. Michael Juda
Harvard-Smithsonian Center for Astrophysics
60 Garden Street, Mail Stop 70
Cambridge, MA 02138, USA
Ph.: (617) 495-7062
Fax: (617) 495-7356
E-mail: mjuda@cfa.harvard.edu