Planmeca Proline EC ceph, Technical Manual

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Chapter F - PREVENTIVE MAINTENANCE
F-2 Planmeca Proline EC X-ray unit
PREVENTIVE MAINTENANCE CHECKS
Technical Manual
2 PREVENTIVE MAINTENANCE CHECKS
2.1 Electrical checks
Annually or after every 10 000 exposures whichever appears first the electrical exposure
parameters of the Planmeca Proline EC Panoramic X-ray should be checked in order to
maintain the initially accurate operation of the equipment despite of the possible long term
component value alterations.
There are no adjustments in the equipment because of its’ self-calibrating microprocessor
based operation and therefore no actual parameter trimming of the kV, mA and exposure time
can be done.If one of the parameters to be checked by this periodical preventive mainte-
nance procedure is found to be beyond the limit values allowed, the corresponding electrical
circuit board is to be changed in whole and sent back to the factory for recalibration that is
done by replacing the faulty component.
The parameters to be checked are the following:
Before exposure:
• kV measurement circuit impedance
• mA measurement circuit impedance
During exposure:
• kV value
• mA value
• exposure time
In order to perform the calibration measurements the X-ray equipment must be powered off
and the rotating arm bottom cover and Generator EMC-cover are to be removed. The cable
connector is disconnected from PSU board connector J1. The multimeter is connected
between the cable connector J1 and ground.
Before powering on the X-ray equipment the circuit impedance measurements should be per-
formed in order to verify the condition of the measurement resistors in the tubehead.
Select resistor mode of the multimeter.
kV circuit impedance measurement
The multimeter is connected between the connector J1: 7 and tubehead ground. Read the
multimeter display.
Acceptable value between J1: 7 and tubehead ground is from 18.60 kohms to 19.0 kohms.