RTI Piranha, Reference Manual, Page: 129 / 181

5. Measurements with the Piranha System
Mammography
2014-06/5.5C
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Piranha & QABrowser Reference Manual
Dental and Panoramic Dental 5.6
This topic will describe how to measure kVp, dose, and time for a Dental and Panoramic
Dental X-ray units using the Piranha only.
Set up the Piranha and the handheld computer according to the description in
Setting
Up the Piranha . To measure kVp for a dental unit is similar to measuring for a
radiography units with the difference that the output level is much lower and the total
filtration is normally around 2 mm Al.
The setup is straightforward and also to get the measured value. Most dental units is
still single phase self-rectified and has 100 % radiation and kV ripple. In the case of
one-phase dental units it is common that only the exposure time can be changed. In
most cases the set tube voltage and current is fixed to about 65 kVp and 8 mA. A
challenge can exist how to find a definition what measured value should be used.
Furthermore the radiation output and the kV waveform are not stable for the first 200 ms
or so, because that the tube filament current in most cases is not regulated.
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