Planmeca Proline CC, Техническое руководство

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Chapter F - PREVENTIVE MAINTENANCE
Planmeca Proline CC panoramic x-ray F-3
Technical Manual
mA measurement circuit impedance measurement
Proceed as measuring the kV circuit but select for mA measurement. Both measurements (if the
latter is needed) should give a resistance value from 378 ohms to 387 ohms. If both results were
out of limits the tube head must be replaced. If only the first result was out the generator proces-
sor must be replaced.
If the first two tests passed check that the calibration unit is connected both to the cable end con-
nectors and to the circuit board connectors and power on the x-ray equipment. After the self test
phase has passed enter the service mode to avoid unnecessary rotation while measuring kV and
mA values.
CAUTION Put the lead radiation protection plate in front of the collimator to avoid radiation during
measurements.
kV - measurement
Select for kV value measurement and select x-ray equipment for kV values from 60 kV to 80 kV
(selected mA value has no effect but 2 mA is recommended to avoid unnecessary radiation),
press the exposure switch at each kV value and read the calibration unit display when the gener-
ator is on (warning sound of higher pitch can be heard), allow few seconds to the calibrator to
settle. The results must be the values selected ± 2.5 kV. If not, the generator processor board is
to be replaced.
CAUTION DO NOT OPERATE THE RESISTOR/BATT BUTTON WHILE THE X-RAY IS OPERATING.
DOING THIS MAY CAUSE PERMANENT DAMAGE TO THE TUBE HEAD.
mA - measurement
Select for mA value measurement and select x-ray equipment mA values from 2 mA to 12 mA
(selected kV value has no effect but 60 kV is recommended to avoid unnecessary radiation),
press the exposure switch at each mA value and read the calibration unit display when the gen-
erator is on (warning sound of higher pitch can be heard), allow few seconds to the calibrator to
settle. The results must be the values selected ± 1.0 mA. If not, the generator processor board is
to be replaced.
CAUTION DO NOT OPERATE THE RESISTOR/BATT BUTTON WHILE THE X-RAY IS OPERATING.
DOING THIS MAY CAUSE PERMANENT DAMAGE TO THE TUBE HEAD.
Exposure time measurement
Enter the x-ray equipment normal operation mode because the rotation is needed for the expo-
sure time measurement. (For cephalostatic exposure time measurements enter the cephalostatic
mode). Select the calibrator exp.time measurement mode. Select 70 kV and 10 mA and push
ready button. (70 kV and 10 mA must be selected for the exposure time measurement because
the calibration unit counts the time from 50% rising edge to 50% falling edge of the kV and mA
values using 35 kV and 5 mA limit values). Push the exposure switch till the end of the panoramic
(or cephalostatic) exposure and then read the calibration unit display. Starting an exposure will
clear the time display.If the exposure switch was released before the end of the exposure Er 00
is displayed on the x-ray equipment clock display and the measurement is invalid.Selecting for
kV or mA exp.time will measure the exposure time from kV over 35 kV or mA over 5 mA, respec-
tively.
CAUTION DO NOT OPERATE THE RESISTOR/BATT BUTTON WHILE THE X-RAY IS OPERATING.
DOING THIS MAY CAUSE PERMANENT DAMAGE TO THE TUBE HEAD.