GE Brivo OEC 715 - Field Size Check and Calibration

Calibration
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4.6.5. I.I. Field Size Check and Calibration
I.I. Field Size Check
1. Select relative field size, open the collimator to the maximum, and take an exposure.
2. Read the BAFT/UBAT tick mark on the boundary of the image. The size of the image should be
within the range of the values below.
Mag Mode
NORM
MAG1
MAG2
Displayed Image Diameter (mm)
210
±
10
155
±
8
115
±
8
3. If the size of the image is out of requirement, I.I. Field Size Calibration shall be performed.
I.I. Field Size Calibration
I. I. Size adjustment is done in the I.I. factory. Adjust with much care only if the Power
Supply is changed or repaired. Always use non-metal flathead screwdriver to adjust the
I.I. potentiometer to avoid short circuit.
1. Loosen the 2 I.I. power supply fixed screws.
2. Disconnect relative cables to take out the I.I. Power Supply. Carefully adjust I. I. Field Size
potentiometer. Below are two ways to fix I.I. power supply in calibration: