Thermo Scientific 48i, Инструкция по эксплуатации

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Operation
Calibration Factors Menu
Thermo Fisher Scientific Model 48 i Instruction Manual 3-19
background correction is a value, expressed in %, that is subtracted from
the O
2
reading to produce the O
2
reading that is displayed.
In the example below, the analyzer displays 0.12% of O
2
while sampling
nitrogen. A background correction of 0.00% means that 0% is being
subtracted from the O
2
concentration being displayed. Therefore, the
background correction must be increased to 0.12% in order for the O
2
reading to be at 0%, i.e., an O
2
reading of 0.12% minus an O
2
background
reading of 0.12% gives the corrected O
2
reading of 0%.
To set the O
2
reading in the example below to zero, use to
increment the O
2
background correction to 0.12%. As the O
2
background
correction is increased, the O
2
concentration is decreased. Note that at this
point, pressing and however, has no affect on the analog
outputs or the stored O
2
background correction of 0.00%. A question mark
following both the O
2
reading and the O
2
background correction indicates
that these are proposed changes as opposed to implemented changes. To
escape this screen without saving any changes, press
to return to the
Calibration Factors menu or to return to the Run screen. Press
to actually set the O
2
reading to 0.00% and store the new
background correction of 0.12%. Then the question mark prompt beside
the O
2
reading disappears.
●
In the Main Menu, choose Calibration Factors > O
2
Background .
O2 BACKGROUND:
O2: 0.12 %
SET BKG TO: 0.00 % ?
 INC/DEC
 SAVE VALUE
RANGE AVG DIAGS ALARM
The O
2
Coefficient screen allows the O
2
span coefficients to be changed
manually while sampling span gas of known concentration.
The display shows the current O
2
concentration reading. The next line of
the display shows the O
2
span coefficient that is stored in memory and is
being used to correct the O
2
concentration. Notice that as the span
coefficient value is changed, the current O
2
concentration reading on the
above line also changes. However, no real changes are made to the value
stored in memory until
is pressed. Only proposed changes, as
indicated by a question mark prompt, are displayed until is pressed.
Note The concentration value will show “ERROR” if the measured
concentration is not a valid span value (either too high or too low). ▲
O
2
Coefficient