OEC 9800C-Arm, Руководство по обслуживанию

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Calibration
Camera Iris
Note: For pre-OPIS system software, use the RUT utility CD.
Iris Stop Verification
1. Before verifying the camera iris setup, ensure that the collimator cover and image tube focus grid are in place on the system.
2. Using RUT (or open UTILITY SUITE, go to RUT and connect), verify that the Generator Sync rate is to 30 Hz. and the
Domestic ABS table is selected. (If Sync rate and ABS table settings are different, temporarily change them to verify or
calibrate the Camera Iris).
3. Place 2 millimeters of copper on the collimator cover so that the entire X-ray beam passes through it.
4. Attach a suitable dosimeter ion chamber to the center of the focus grid on the image tube.
5. Verify that the following image tube input doses are produced while making NORMAL Magnification mode Auto Fluoro
exposures through the copper filters (Dose corrected for temperature and elevation):
•
9-inch I.I. – 4.5 ±0.3 mR/minute
•
12-inch I.I – 3.3 ±0.2 mR/minute
6. Verify that the following closed iris image tube input doses are produced while making NORMAL magnification mode 30 PPS
HLF exposures:
•
9-inch I.I. – 32 ± 3.0 mR/minute
•
12-inch I.I – TBD ± TBD mR/minute
Re-calibration of the camera iris is required if the image tube input dose is outside of the ranges listed above.
7. If system settings were changed in step 2, restore the settings now.
8. Remove the copper from the collimator cover and the ion chamber from the center of the focus grid.
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Service Periodic Maintenance Contents Schematics Illustrated Parts Installation