User name Glesener
Log entry time 10:44:04 on July25,2005
Entry number 149409
keyword=Closing JT valveSince we will be without beam for quite some time, I am closing the JT valve in steps of 1% and turning down the fan. So we can know how the JT valve setting corresponds to CHL flow and HPH power, I wrote down some values for these as I changed the valve.
JT cryo HPH
(%) (g/s) (W)
-- ---- ---
65 21.4
63.2 20.3 315
62.0 19.5 280
60.0 18.1 250
58.0 17.2 220
56 16.1 175
54 14.7 148
52 13.7 105
**Changed fan speed to 10% (24 Hz).**
52 13.7 208
50.5 12.5 170
48.7 11.2 130
47.0 9.5 65
Note: I changed the fan speed too quickly, so the pressure quickly rose to 214 psi, leveled off quickly, and gradually fell back down to 211 psi.
The JT valve step size was set to 1 as I closed it, but the changes look more like 2%.
FIGURE 1
FIGURE 2
