Chapter 3 Calibration
HF Series X-ray Generators - Service Manual Revision W
Quantum Medical Imaging, LLC 3-45
7. Verify 400L MA appears in the center display box and Measure, Cali-
brate appears in the top right field.
8. Take an exposure at the setting indicated in the center display box (i.e.,
60 kVp, 400L mA, 100.0 mS).
9. On the Dynalyzer Digital Display or on mAs meter, observe the measured
mA value. (Ideally, this value should be 400 mA or 40 mAs.)
10. If not 400 mA, adjust the value in the Measure MA#2 field up or down
by pressing the key next to the up or down arrow, respectively, until the
Measure MA#2 field is set to the value displayed on the kVp meter.
Each time the key is pressed changes the MA value up/down in one-tenth
increments.
11. Press key next to the Save Calibrate field to save the 75S and 400L mA
calibration entries. The MA Calibration Menu (First Measure) should be
displayed.
12. Take 60 kVp, 75S mA, 100 ms and 60 kVp, 400L mA, 100 ms exposures.
The measured kVp values should correspond with the indicated kVp set-
tings within 3% tolerance; and the measured mA values should corre-
spond with the indicated mA settings at least within 4%+1 mA. If not,
repeat kVp and/or mA calibration as described in the previous para-
graphs.
Note: The Power Supply Board’s +48 VDC output
may require adjusting (using potentiometer
A6R17) up to +55 VDC (max.) in cases where
long-length high tension cables are used and/or a
heavy duty x-ray tube is installed. This can be
determined by measuring the mA output (using a
Dynalyzer or mAs meter), of an exposure taken at
40 - 50 kVp and the highest mA station available.
The mA measured should be the same as the indi-
cated mA (within specified tolerance). If mA out-
put is too low, increase the +48 VDC voltage
output as required, but do not exceed +55 VDC.
13. If the system is equipped with QG-AEC option, perform AEC Calibration
procedures. Otherwise, calibration is complete. To return to the Service
Calibration screen, press the key next to the Main field.
CAUTION! If using a mAs meter, re-connect the
green/yellow wire marked "MAS METER" to the
ground stud on top of the H.V. Transformer (see
Figure 3-32).
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