@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ @ @ MTA Monitoring Report 6/09/00 - 6/15/00 @ @ @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Archive of all weekly reports http://asc.harvard.edu/mta/REPORTS/weekly.html Archive of Monthly reports http://asc.harvard.edu/mta/REPORTS/MONTHLY ************ CTI trend ************* CTI of CCD4 dropped on 2000-06-10T01:31:22 (SQUEEGEE V) SQEEGEE VI also listed : Date Node 0 Node 1 Node 2 Node 3 al ka _____ 2000-06-10T02:31:21@ 3.358+-0.094 3.795+-0.160 3.956+-0.162 3.795+-0.151 2000-06-10T01:31:22# 2.876+-0.162 3.246+-0.214 3.380+-0.252 3.339+-0.229 2000-06-15T19:01:20* 3.263+-0.216 3.698+-0.252 3.819+-0.264 3.735+-0.289 ti ka _____ 2000-06-10T02:31:21@ 2.019+-0.045 2.249+-0.084 2.358+-0.071 2.318+-0.070 2000-06-10T01:31:22# 2.420+-2.709 0.356+-3.119 1.675+-0.079 1.626+-0.088 2000-06-15T19:01:20* 1.872+-0.076 2.114+-0.101 2.202+-0.108 2.119+-0.120 mn ka _____ 2000-06-10T02:31:21@ 1.779+-0.030 2.013+-0.048 2.078+-0.043 2.035+-0.055 2000-06-10T01:31:22# 1.422+-0.066 1.622+-0.073 1.676+-0.079 1.628+-0.089 2000-06-15T19:01:20* 1.609+-0.073 1.820+-0.089 1.891+-0.093 1.838+-0.090 @= typical #=SQUEEGEE V *=SQEEGEE VI Detrended Mn Ka CTI jumped up after May 20, 2000. This is due to drop of the drop amp average (normalized to 70): Date Drop amp average __________________________________________ 2000-05-20T10:41:20 0.908177342124718 2000-05-25T04:45:42 0.735982214114696 2000-05-25T18:35:21 0.718610065385378 2000-05-28T08:49:04 0.764164355062413 2000-05-31T00:45:18 0.752498921018558 2000-05-31T00:45:18 0.752498921018558 2000-06-02T16:55:37 0.765399109284001 2000-06-02T16:55:37 0.765399109284001 2000-06-05T07:03:38 0.738658505043538 2000-06-07T23:20:24 0.745865112691747 2000-06-07T23:20:24 0.745865112691747 ************** MTA Problem Tracking ***************** Although none of them are new, many warning are issued on 6/15/00. Many of them are same as the last week's warning (reaction wheel related). ESAPYI,AOACHIBK, AWD3TQI, AIOBP5CV, C28VMONB, CUS0B28V, CIUB5V, CIUB15V, AWD1TQI, AWD4TQI, AWE5TQI, AOAUTTXN, 5EHSE400 ******** Trending *********** ACIS Electronics side A 1DEP3AVO and 1DEP2AVO: new downward trend observed. Not significant. Both dropped about 0.1 V (~0.4%) this week. Software note: There is still a bug (or two), and some of the plots are not complete. ************* Telemetry *********** Nothing new this week. During day 6/14, some of the data are missing (e.g., OBA Aft Bulkhead HAFTBGRD1/3) this is probably a CXCDSOPS error. *********** ACIS Focal Temperature ******** Acis focal plane temperature peaked three times. Day (DOY) Temp (C) Width (DAY) 159.70 -110.82 0.22 162.35 -111.79 0.24 164.99 -111.48 0.24 *********** Photon Page ************ Due to a web page problem, we could not get information about each object this week. Acis OBSID DETECTOR GRATING TARGET ANALYSIS - --------------------------------------------------------- 49898 ACIS HETG NGC 1399 NO Grating? 879 ACIS PSS 1317+3531 OK 878 ACIS PSS 1057+4555 OK 670 ACIS 1812-12 OK 321 ACIS NGC 4472 OK 380 ACIS M82 OK 926 ACIS MS 1008.1-1224 OK 375 ACIS HE 1104-1805 OK 704 ACIS HETG 4U 1735-44 OK 626 ACIS HD 113703 OK 881 ACIS PSS 1443+2724 OK 627 667 ACIS 1746-331 OK 662 32 HRC-S VEGA OK 21 HRC-I VEGA OK New CTI Mesurments processed: 62027, 62028, 62882,62881,62030(Squeegee V) ******** Gratings ************** From Michael McGuirk Jun_14_2000 The HETG B-side retraction limit switch failed last night. All symptoms of the failure are identical to the A-side failure May 8, 2000, i.e. the switch appears to function, but the trigger point has moved to a position after the end of travel bumper spring is compressed. When the switch finally turns off the motor, the spring pushes the grating back, restoring power to the motor. This cycle continues until power times out. The grating rest position leaves the limit switch indicating "not retracted". The two limit switches are actuated by a wide lever arm pivoting on an axis defined by an adjustable bearing on each side. My scenario for the failure is that the bearing on the A-side moved out of adjustment, allowing the A-side limit switch trigger point to change. The B-side trigger point changed also, but not enough so it did not function. Over the subsequent ten actuations, the lever moved enough so the B-side trigger point moved to allow compression of the bumper spring before the motor turns off. TRW and EKC are evaluating this scenario and alternatives. Jun_15_2000 (UT) from RAC 0200: both MCE-A and MCE-B retract limit switches show "NRET". 0204: HETG insertion: both MCE-A and MCE-B limit switches show insert state. MCE-A and MCE-B pot angles are 6.3 degrees, as expected. 0210: MCE-A and MCE-B insert limit switches now show NON-INSERT. This is not expected. 0218: CAP proceeds, MCE 28V and 5V turned off. 0222: Return to normal point mode. 0226: CAP 619A complete. Although the HETG insert limit switches show non-insert, and cannot be retracted by software command, Chandra is in a suitable state for performing science for the next few days. Jun_16_2000 (UT) from RAC 0028 run script M_HETG_HW_B_INS5 to fully insert HETG. 0031 both HETG insert relays show INSERT - success! from Keith Havey Jun 16 Most likely angle error was ~ 0.3 degrees. ******** Note from Experts ************** About 1DPICBCU yellow warning limits (from Peter Ford (pgf@space.mit.edu). The FEPs were powered off during SI Safing so the B-side DPA was only powering a halted BEP-B board. In this state, it is quite normal for 1DPICBCU to run under 0.3 amps. It has averaged ~0.26 amp since first on-orbit activation whenever its FEPs are powered off. The yellow limit might well be lowered to 0.24A. -From SJW, We are in the process of changing this limit.