XZeal Z70 M, Руководство пользователя

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All measurements should be done with the equipment supplied at nominal line voltage
according specified at the 2.1. item. The tolerances on the measured values must be considered
the precision of the each measurement instrument.
Only specialized technicians must make the measures.
Warning
Measurements have to be done by trained personnel only to avoid risk of electrical shock.
10.1 Line Voltage
The line voltage can be measured using a voltmeter for alternate current within the proper
range.
10.2 Anode Voltage (kVp)
The kVp level is the actual peak value of the anode voltage which stabilizes once the pre-heating
time of the filament has elapsed (in about 200 ms) and the high voltage transformer is actually
loaded. The kVp level can be measured with a non-invasive kVp meter placed in front of the
Beam Limiting Device following the instructions in the User Manual of the instrument. A correct
measure can be done with an exposure time of 500 ms or more having introduced a delay of the
reading instrument of about 300 ms to allow the voltage level to stabilize after the pre-heating
time has elapsed.
10.3 Anode Current (mA)
Warning
To prevent high voltage shock make sure the system is disconnected from power supply when
the connections to the measurement points are performed.
Electric discharge might occur in case of improper operation.
The anode current in mA is the actual average value of the tube current which raises when the
filament has warmed-up, after the pre-heating time has elapsed.
Remove the Tubehead cover to access the two points of measure.
The anode current can be read with DC voltmeter connected in each point with the 1V
corresponding to 1mA (use 1000 Ohm precision resistor for the measure).
10.4 Exposure Time
The Exposure Time can be measured with a non-invasive timer meter placed in front of the
Beam Limiting Device following the instructions in the User Manual of the instrument.
In order to assure the requested exposure time (irradiation), the pre-heating time of the insert
used, which has been set-up at installation, is taken into consideration.
The actual switch-on time of the Tubehead assembly is therefore the sum of the filament
pre-heating time and of the requested exposure time.
Dental X-Ray Unit
Z70
70kVp - 7mA
20
10. Measurements (Informative only)
Appendix - Manual