23 march 2004. Bari. TVB Post Test Review.
INFN - Bari,Pisa
The review started in the afternoon as all the attendees arrived at or during the lunch hour.
The agenda was presented by NM. TMc had a question about the behavior of the TEm that was seen during the TVB tests at ALS.
JG gave a thanks for the INFN work for the TVB.
SR presented the test overview. Goal of the test as the TVB and correlation of the model and to correlate the TCs with the thermistor.
There were 9 cases planned and of this only 7 were performed due to time constarints. The required temp cycles thqat were foreseen for this test were deleted by general agreement of all parties concerned. @ balance cases in the hot, 3 balance cases in the mid and 2 cases in the cold. The test pahse was conducted on schedule and as predicted including the test set-up. The setup description was given - see charts for details. Some details of the TEM current consumption which was not stable during the test.
AB did a brief explanation of the MCM configuration of the EM tower for this test. It was also possible/true that the power dissipation was not exactly flight type by about 10%. The second last case was not of the nominal stablization duration of 4 hours >= 0.1 degrees. The test log is on the BARI WEB SITE.
AT presented the MGSE used for the TVB - see charts for details. The thermal straps were of dry joint as there was no agreement on the final design for flight. The grounding of the test setup is going to be very important for the next TV test of Tower A.
NS gave the presentation of the test article and the instrumentation. The pedigree of the MCM in each tray will be put in the report. The +Y side wall was the most instrumented of the 4. C05 was instrumented with TC next to the thermistor.
FG is giving a quick talk of the results. The worst performance was of the TEM unfortunately. The delta of the strap was found to be +/- 1 degree C with in the accuracy of the Tcs used. The guard shield e was 0.14 and that of the base plate is 0.67. The temp of the GS, TB and the tower were measured and was not always under control due to difficulty in the control. The TEm temperature was between 10 and 28 degrees C. The thermal strap and the flexure are playing some part in the conductance. The delta temperature between the top and bottom of the side wall is to be presented more clearly in the report.
NM presented the thermistor results where he had to fish out the data due to the offset of the reading when the Tower was powered. The data was corrected by NM and presented. A chart showing the correlation between the Tower outside instrumentation and the thermistor data. the requirement for a flight qualified TEm for the Tower TV tests are a must and this has to be worked with SLAC for the schedule of the Tower A tests.
The meeting was changed to discuss the next test of the tower A. the current test will and should last 5 days in ALENIA time. there is a big discussion about the thermal cycle requirements.
24 March 2004
The discussion centered around how to proceed with the test for Tower A. One thing that has become clear is that the next test will have to be done in another Tv chamber where ALS will be using a chiller in a vac chamber. The tentative design centers around the use of a passive guard shield around the Tower of the 3 options that were discussed. SLAC (JG) will do analysis to show that this is acceptable for the thermal cycling of the Towers. The results of the analysis will be available next friday 2 April, 2004. the baseline consideration is that ALS will provide a chiller with the characteristics that were defined by JG during his visit in December to ALS.
The next test schedule was discussed and it came to light that the schedule published by TV showed ALS tests going on in August. ALS will not be available for any activity in August and that all test activity will have to be finished by the end of July or completed in September. This fact was communicated to TV/RJ by NM via email. There is no information available on the status of the EGSE that is required for the Tray and Tower level tests. This matter will be discussed between JG and RJ at SLAC.
There is a thermal balance (mini) designed into the first cycle of the Tower A Tv tests at present. There is a time constraint to this and INFN wants to complete the tests in 5 working days (test time only). The need for this TB is 1) this will be the first flight representative Tower to be thermally tested 2) the correlation of the model with the EM Tower test data may not be satisfactory. The real need for this TB will be established at the TMM correlation presentation scheduled for second half of May. The document --408 does require that PFM go through a TB test.
INFN hospitality was insurmountable!!