Hologic DISCOVERY A, Technical Manual

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Discovery QDR Series Technical Manual
4-18
Note: The last calibration scan data is saved in the file MOTOR_TY.DAT. You
can reanalyze the data–e.g., after editing SQDRIVER.INI–by typing the
command CALIBRATE @MOTOR_TY.DAT
at the MOTOR$TY>
prompt in SQDRIVER.
4.6.0.4 MOTOR$TX
If you have replaced the encoder, before beginning this procedure, loosen the set screws
that secure the encoder coupling to the pulley shaft and make sure that the tank assembly
is not under the operator console. For normal installations, this is unnecessary.
1. Select the TX motor device driver by typing:
MOTOR$TX<Enter>
2. At the MOTOR$TX> prompt in SQDRIVER, type:
CALIBRATE<Enter>
The program prompts:.
The program moves the TY (W only) and AY motors to their center positions
and prompts:.
The above message is always displayed when calibrating MOTOR$TX. This is
the normal message for a QDR-4500. The message was not changed for DIS-
COVERY systems.
3. Press
<Enter>
and the program prompts:
4. The program moves the TX motor to the left. When TX hits the left mechanical
stop the first time press <Esc>.
5. Check the position value. It must be 1000±5. Adjust if necessary.
If out of range, loosen the coupling setscrew and manually rotate the encoder
until the readback is 1000±5 (i.e., in the range 995-1005) and then tighten the
coupling setscrew.
6. Repeat the calibration procedure above but now, when AY hits the left mechani-
cal stop, press
<Enter>
.
The program switches to graphics mode and draws the Encoder Vs Distance cal-
ibration grid. It steps the TX motor in by 1" increments until the inner mechani-
cal stop is hit. The program plots the encoder data during the scan (in raw
encoder units, 0-4095).
7. Press
<Esc>
at anytime during the scan to terminate the calibration procedure.
Press <ESC> to stop calibration.
Use the Table IN / OUT switch to move the C-Arm to 0 degrees.
Press <Enter> when the C-Arm is positioned.
Press <ESC> to stop calibration.
Press <Enter> when the TX motor reaches the OUTER mechanical limit.
Press <ESC> to stop calibration.