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    User name R. Michaels

    Log entry time 11:08:10 on March 2,2012

    Entry number 362707

    This entry is a followup to: 362704

    keyword=cycled Q2,Q3. magnet status

    Bob M. and Igor K.
    At 10:15 we set P0 = 2.254 GeV/c

    We cycled quads Q2 and Q3 per instructions in halog 362704.
    Q2,Q3 to 1400 A, except for R-Q3 which goes to 1100 A.

    Note: we found that if we put in the currents in the blue dialog
    box, the Quad would go there but only stay for a brief moment (1 sec).
    In order to make the Quad stay at the max current, we had to
    turn off the regulator. Click on the GeV/c button and click
    "off" for P0 regulation. Then click "on" after a few minutes
    at max current.

    We checked the polarity of the gaussmeter readings. They look
    correct for negative (electron) polarity. It is a pattern of
    positive and negative values which are well known. However, we
    also found that the "polarity" button on Left HRS Q3 power supply
    showed Positive.
    This looks wrong, but we suppose (from the gaussmeter) that the
    polarity is actually Negative. See fig 1.

    Note, the gaussmeter readings are the fundamental thing to go by.
    The rest (N or "polarity" in a GUI) are just software, can be wrong.

    Present status (fig 2) : all magnets set, except R-dipole, but that's
    known to take hours to settle.


    FIGURE 1

    FIGURE 2