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    User name LeRose

    Log entry time 12:42:47 on October15,2001

    Entry number 74804

    keyword=Left Arm High P

    11:00 starting to ramp up: all magnets are set to correct polarity at 100 amps
    11:10 set left arm p0 to 4.0
    11:22 quads all at 4.0 GeV/c, dipole still ramping (<1000 Amps)
    11:27 dipole at 3.4 GeV/c and ramping
    11:45 dipole at 4.0, set to 4.1 GeV/c
    11:48 quads at 4.1
    11:58 dipole at 4.1
    12:02 set to 4.2
    12:09 lost Q1 He level fault looks like a bad sensor or software run amok(Ed Folts will investigate)
    q2 (1808.51 amps) q3 (1672.12 amps) and dipole hold at 4.2
    12:16 set to 4.3 almost imediately lost q3. dipole and q2 continue up
    12:22 q2 arrives at 4.3 (1851.6 amps)
    12:33 Dipole reaches 4.3 (1677.03 amps

    q2 and the dipole successfully set to 4.3
    q1 failed due to He level fault that may be a bogus level reading
    q3 held at 4.2 (1672 amps) but failed almost imediatley upon setting for 4.3

    Dipole controls don't seem optimal. Original Isets are too low. You ask for an increase from e.g. 4.0 to 4.1 and the current drops 60 amps before turning around and going back up. Also the timing on the regulation loop seems very sluggish (more like what would be required on the right dipole. See plot in next halog

    FIGURE 1

    FIGURE 2