Sabio 2010D, Руководство по эксплуатации

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Internal UV Ozone Photometer Page 9-20
For more details on performing internal calibrations with the
2010D
, refer to Section 8, "Internal Calibrations". Though the
Photometer calibration is very similar to other internal
calibrations, there are a few differences and considerations that
should be addressed:

The other internal calibrations have both control and monitor
correction equations. The Photometer, being a measurement-
only device has only a monitor equation.

Other internal calibrations are used not only for adjusting
for calibration errors, but also for converting voltage units
to engineering units of measure. For example, for ozone
generator calibrations, the control and monitor values are
both in voltage units, while the external ozone standard is in
terms of concentration (PPB, PPM, etc.). In the case of the
Photometer, however, both the Photometer (monitor) and
external ozone standard values are in terms of concentration
units.

The values entered into the O3Gen column during an interactive
Photometer calibration are used to activate the ozone
generator in order to produce an ozone concentration for
comparison of the Photometer and external ozone standard.
This column of values is not used to calculate Photometer
calibration coefficients.

The Sample Temperature, Pressure, Flow and Lamp Temperature
are provided so a record of the environmental conditions at
the time of the calibration will be known. Though these
parameters are provided automatically when an interactive
calibration is performed, they are optional and may be omitted
if manually entering calibration data.

IMPORTANT: The "Photometer" column of numbers in the New or
Edit Table screens (Figure 9-) represents the uncalibrated
photometer reading. If a calibration table is to be generated
manually by comparing the photometer to an external standard,
the previous calibration should be removed first by selecting
"New Coefficients" under the "Photometer Calibration" menu and
setting the Photometer coefficients A, B and C to 0, 1 and 0,
respectively. If this is not done, the resulting calibration
table will be erroneous, since a calibration will have been
applied on top of a previous calibration. This is not
necessary when an interactive calibration is performed, since
the automatically supplied Photometer reading is always the
uncalibrated value.