Chapter 9 Page no. 1652
JC-CAL-A-001.fm
GE Healthcare Senographe DS
Revision 1 Service Information and Procedures Class A 2385072-16-8EN
Job Card CAL A001 - Heater Current Scale Factor
6. Select SETUP/MeasI on the X-ray Console.
7. Enter and confirm the measured filament current value from the multimeter for this first calibration
point.
8. Select SETUP/SETUP/2nd pt/CALIB on the X-ray Console for the second calibration point.
Note:
The default filament current command value for this second point is +5.000E+00 (5.0) A.
9. Press the Exposure button on the X-ray Console (no X-rays are produced); hold it until the
ammeter reading stabilizes (this may take a few seconds).
10. If it is required to apply a correction to the measured value, follow the instructions given in section 6-
2-1, Measurement Correction on page 1651.
11. Note the filament current value measured by the multimeter.
12. Release the Exposure button .
13. Select SETUP/Meas on the X-ray Console.
14. Enter and confirm the measured filament current value from the ammeter for this second calibration
point.
15. Select SETUP/SETUP/calcul/VALID on the X-ray Console. This executes the calculation of the
scale factor and fixed offset of the filament current command from the software.
6-2-3 Check the calibration accuracy.
1. Select SETUP/1st pt/CALIB on the X-ray Console.
Note:
Again, the default filament current command value for this first point is +4.000E+00 (4.0) A.
2. Press the Exposure button on the X-ray Console (no X-rays are produced) and hold it until the
multimeter reading stabilizes (this may take a few seconds).
3. Note the filament current value measured from the multimeter.
4. Release the Exposure button .
5. Select SETUP/SETUP/2nd pt/CALIB on the X-ray Console.
Note:
Again, the default filament current command value for this second point is +5.000E+00 (5.0) A.
6. Press the Exposure button on the X-ray Console (no X-rays are produced) and hold it until the
multimeter reading stabilizes (this may take a few seconds).
7. Note the filament current value measured from the multimeter.
8. Release the Exposure button .
9. Whatever Fluke 87 type is used (first generation, type 3 or type 5), the expected results are the fol-
lowing
• 4.0 ±0.12 (+/-3%) A for the first point and
• 5.0 ±0.15 (+/-3%) A for the second point
If the results are within these tolerances, the calibration for this X-ray tube track is finished. If the
results are out of tolerance, repeat the calibration procedure in section 6-2 and the check procedure
in section 6-2-3 for the same X-ray tube track.
Note:
Performing the calibration procedure once is normally sufficient for correct calibration.
If it is necessary to perform the calibration procedure more than once, the measured values of cur-
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