Planmeca Proline EC ceph, Техническое руководство

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Chapter D - ADJUSTMENT & CALIBRATION
D-32 Planmeca Proline EC X-ray unit
AUTOMATIC EXPOSURE CONTROL (AEC) CALIBRATION
Technical Manual
During the exposure the AEC-signal value is shown on the main display. Set this value to
approx. 60 with the gain trimmer located on the Cassette limit PCB. Turning the trimmer
clockwise decreases the value and turning it counterclockwise increases it. Repeat the
adjustment until the correct value has been reached.
Figure 35
NOTE The final adjustment of the AEC-signal during the exposure must be done in the nor-
mal mode.
Final adjustment in normal mode
NOTE In the normal mode the AEC-signal is only shown on the main display if you previously
were in the film density adjustment mode. In case the AEC-signal is not shown on the
main display, enter the service mode and enter the film density adjustment mode. Then
exit the film density adjustment and the service modes and the signal can be seen on
the main display.
To exit the service mode press the hidden key briefly.
Drive the X-ray unit to the exposure position by pressing the ready key.
Take an exposure. Note that you can stop radiation in the middle of the exposure (approx. 4
seconds after starting the exposure). An error code 00 will appear on the display and start to
flash. Press the CTL-key to clear the error code.
After the exposure the difference between the offset value and the AEC-signal during the
exposure is shown on the main display. Set this value to 51 ±1 with the gain trimmer located
on the Cassette limit PCB. Repeat the adjustment until the correct value has been reached
and check the value by taking at least two exposures.
NOTE In the service mode the difference between the offset value and the AEC-signal value
of the latest exposure (taken in the normal mode) can be seen by pressing the CTL key.
To exit this mode press the CTL key a second time.
U 60
AdjAEC
.eps
Adjust the
AEC-signal with the gain trimmer
.
Hidden
key
READY
PRET