Planmeca Proline CC, Technical Manual

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Chapter D - ADJUSTMENT & CALIBRATION
D-28 Planmeca Proline CC panoramic x-ray
Technical Manual
8.2 Base value adjustment
The default kilovolt value, i.e. the value that is used when the AEC exposure starts, is 68 kV. The
film density is adjusted by changing the default milliampere value. The adjustment range is from
-3 to +3. The density value 0 corresponds the mA value 8. Changing the density value will
change the mA value as follows: one density step equals to one mA step. The negative value
decreases the mA value from the value 8mA, whereas the positive value increases it.
To find the exposure values that give the film density closest to value 1.0 ±0.1 OD the test expo-
sures are taken. The films are either compared to the reference film which density is approx. 1.0
OD (supplied with the system), or the film density is measured using a film densitometer.
It is recommended to start with exposure values 68kV and 7mA and check the film density. In
case other exposures are needed, decrease/increase the mA value until the correct film density
is achieved.
Place the AEC calibration filter to the front of the first primary slot (primary slot number 0).
Move the cassette carriage to the loading position.
In the darkroom open the cassette and place a film inside the cassette. Close the cassette. Slide
the cassette into the cassette holder.
NOTE The film density adjustment must be performed in normal panoramic mode. Make sure
that the unit is NOT in the AEC mode, i.e. make sure that the auto key indicator light is
NOT on.
Select a kilovolt value of 68 and a milliampere value of 7.
Drive the x-ray unit to the exposure position. The rotating unit will turn to the start position and the
indicator light will come on.
Take an exposure.
kV mA
Density
value
68 5 -3
68 6 -2
68 7 -1
68 8 0
68 9 1
68 10 2
68 11 3
kV
mA 7 6 8
READY
PRET