Planmeca Proline EC ceph, Technical Manual

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Chapter D - ADJUSTMENT & CALIBRATION
Planmeca Proline EC X-ray unit D-31
AUTOMATIC EXPOSURE CONTROL (AEC) CALIBRATION
Technical Manual
8.3 Adjusting the AEC-signals
NOTE Take five 10 seconds exposures in the service mode with a kilovolt value of 68 and a
milliampere value of 7 before adjusting the AEC-signals.
Make sure that the unit is in the service mode and that the AEC mode is selected. If needed,
enter the AEC mode by pressing and holding down the auto key until the indicator light will
come on.
In the service mode the AEC detector offset value (base signal) is shown on the main display
when the unit is in the AEC mode and no exposure is taken. Set the offset to value 8 ±2 with
the offset adjustment trimmer located on the Cassette limit PCB. Turning the trimmer clock-
wise increases the value and turning it counterclockwise decreases it.
Figure 34
After the offset value is set the AEC-signal during the exposure is adjusted. Check that the
AEC calibration filter is in the front of the primary slot.
In the darkroom open the cassette and place a film inside the cassette. Close the cassette.
Slide the cassette into the cassette holder.
Protect yourself from radiation and press the exposure button.
CAUTION Radiation is generated when the exposure button is pressed. Take adequate protection
measures. Keep the exposure time as short as possible.
U 8
AdjAEC
.eps
Adjust the offset.