Planmeca Proline EC ceph, Technical Manual

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Chapter D - ADJUSTMENT & CALIBRATION
Planmeca Proline EC X-ray unit D-27
AUTOMATIC EXPOSURE CONTROL (AEC) CALIBRATION
Technical Manual
8 AUTOMATIC EXPOSURE CONTROL (AEC)
CALIBRATION
NOTE In case the X-ray unit is equipped with optional Automatic Exposure Control (AEC), the
AEC calibration must be performed after the AEC retrofit kit installation and whenever
the panoramic X-ray beam is adjusted. The AEC calibration is performed after the pan-
oramic X-ray beam adjustment.
Perform the AEC calibration in the following order:
1. Check/adjust the panoramic X-ray beam.
2. Adjust the positions of primary slots number 0 and 1 so that the AEC signal value is as
large as possible.
3. Adjust the base value so that the film density is 1.0 ±0.1 OD.
4. Adjust the AEC detector offset value (base signal) to value 8 ±2. The offset value is shown
on the main display when the unit is in the AEC mode and no exposure is taken.
5. Adjust the AEC-signal value to approx. 60. During the exposure this AEC-signal value is
shown on the main display.
6. Fine adjust the AEC-signal in normal mode.
8.1 Checking/adjusting the primary slot position
After the panoramic X-ray beam adjustment the AEC-signal must be checked. The position of
the slot must be adjusted so that the AEC-signal value is as large as possible.
Enter the service mode: press the CTL-key and simultaneously press and hold down the hid-
den key (to the right of the PAN key) until the temperature of the tubehead appears on the
display (about four seconds). The ready key indicator light will start to flash. This indicates
that you have entered the service mode.
Enter the AEC mode by pressing and holding down the auto key until the indicator light will
come on.
Place the AEC calibration filter to the front of the primary slot. Note, that in the panoramic X-
ray unit you have to tape the AEC calibration to the primary slot mechanism. You will leave
this filter in place for the entire AEC calibration procedure.
Figure 33
+
Hidden
key
CTL
AUTO
cc-kalibrointi.eps
AEC calibration
filter
Aectool-EC-ceph.eps
Pan/ceph X-ray unit Panoramic X-ray unit