ThermoFisher Scientific 146iQ, Инструкция по эксплуатации

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Thermo Scientific 146iQ Instruction Manual 4-1
Chapter 4
Calibration
Regular verification of the performance of, and if necessary, calibration of
the various modules of the multi-gas calibrator is recommended in order to
achieve optimal performance of the instrument. These various modules of
the 146iQ are as follows:
●
Mass Flow Controllers (MFCs) : Achieving accuracy of calibration
source gas mixtures is dependent largely on the accuracy of the various
mass flow controllers (Zero and Gas) used to generate them from
bottled gases. The 146iQ provides a set of inherently linear mass flow
controllers, operating on the principle of Multiple Parameter Laminar
Flow measurement, that are ideal for this task. The accuracy of their
output should be periodically verified, and if necessary, adjusted.
●
Ozone Generator Calibration : If the 146iQ is equipped with the
optional ozone generator, its output should be periodically calibrated.
●
Photometer Calibration : If the 146iQ is equipped with the optional
photometer, its performance should be periodically verified, and if
necessary, adjusted against an external transfer standard.
The inherent linearity of the MFCs result in a more accurate and more
predictable device due to the device’s tendency to naturally follow the pre-
defined calibration curve. Additionally, the superfluousness of the need to
“linearize” output over the entire measurement range of the MFC implies
that the calibration can be customized to include anywhere between 2-7
calibration points, ideally spread out uniformly over the measurement
range. In order to calibrate the individual MFC outputs, properly
calibrated NIST traceable flow meters with the right measurement ranges
are required. The following step-by step procedure should be adhered to,
for each MFC, to ensure the most accurate mix gas output during normal
operation.
1. Connect a source of appropriately pressurized (20

40 psi) clean, dry air
to the ZERO AIR IN port on the rear panel of the instrument.
2. Connect an appropriate flow meter to the outlet of the MFC being
calibrated.
Calibration of
the individual
MFC outputs