ARIBEX Nomad Pro 2 - Optional Calibration Checks

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7.2 Optional Calibration Checks
The NOMAD Pro 2 is factory calibrated and tested prior to release (see your Certificate of
Conformance) and there are no adjustment options. A self-diagnostic is completed each
time an exposure is taken. However, the optional checks listed below may be performed
by a qualified technician as desired. Some locations may require initial and periodic checks
as a condition of use.
Set up a calibrated Performance Meter (such as the Victoreen NERO mAx model 8000)
according to manufacturer’s specifications to detect and report the following: X-ray Tube
Voltage [kV Effective Mode], Radiation Time [ms Effective Mode], and Dose [mR Average
Mode]. The filter card for the Test Detector should be in the 50–100kVp position.
Measurement Method: Final performance measurements are made using a NERO
mAx model 8000 X-ray meter from Victoreen. Tube current (mA) is sensed across a series
connected resistor with an accuracy of ±1% and measured using a digital multimeter,
prior to encapsulation; the NOMAD Pro 2 has no provision for external measurement
of beam current after final manufacture. Exposure time is measured during the entire
exposure, referenced to 75% rise/fall. Accelerating voltage (kV) is measured at both peak
(kVp) conditions and effective conditions (kVeff), which is the equivalent kV as if the kV
were constant through the whole exposure time. Linearity is calculated per IEC60601-2-7,
50.102.2a.
This X-ray unit may be dangerous to the testing technician and any bystanders unless safe
test exposure factors, such as placing the test detector in a lead lined box or using a
protective lead apron and thyroid collar, are observed.
Enable the NOMAD Pro 2 and, with the cone perpendicular to the test detector, make
exposures into the test detector and capture the resulting data.
Compare the results with the factory release parameters (indicated in the chart below). For
results outside these parameters, discontinue use and contact your dealer/distributor or
Aribex.
Test
Description
Acceptance
Limits
Timer Settings and Corresponding Acceptable Ranges
20 ms 40 ms 400 ms 600 ms 1000 ms
kVp (eff) Accuracy 60kV ±10% 54 to 66 54 to 66 54 to 66 54 to 66 54 to 66
Timer Accuracy
Setpoint
±10%, +1ms
17 to 23 35 to 45
359 to
441
539 to
661
899 to
1101
A duty cycle of 1:60 is required after each X-ray discharge to prevent over-heating
damage to the X-ray tube.