• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name Geraud

    Log entry time 05:40:14 on juin17,2000

    Entry number 43999

    Followups:

    keyword=Cryotarget coolant pressure return

    The cryotarget coolant pressure return (sensor PT83) has been slowly increasing since the beginning of the shift. At some point it reached the HIGH limit which was set to 50.
    The accelerator was down at this time, and the crew chief said they were probably introducing some fluctuations in the ESR. It turned out that it didn't stop when the MCC was done.
    The pressure kept increasing and rised the HIHI level of 60. Then it started decreasing again back to a more stable level of 55.
    Closing the JT valve had some effect at the beginning of the phenomenum by decreasing the pressure to about 46., but then it increased again.

    Now the beam is back with 50uA and the valve is opened to the value of 30.

    I noticed that some temperature readbacks don't seem to work very well:
    DT84 = 253.8
    DT152 = 141.0
    Is that normal??

    I just tried to open the valve to 35 and the pressure instantly rises to 56.7; this doesn't look like a good idea to me, so I put it back to 29 and the pressure goes back to 54.5.

    It seems to me that there is a correlation between the JT valve operation and the pressure.