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Note:
To abort the zeroing and proceed to Span calibration, press the Left key at any time during
the process. A confirmation ‘Zero aborted!’ will appear, followed by the Span calibration menu.
When complete, this message “Zero Calibration Done!” is shown, and the display automatically
moves to the Span Calibration menu.
Span Calibration
This procedure determines the second (and third, if 3-Point Cal is selected in Monitor Setup)
point(s) of the sensor calibration curve. One or two cylinders of standard reference gas (span gas)
fitted with a 500 cc/min flow-limiting regulator or a flow-matching regulator is the simplest way to
perform this procedure. (A flow-matching regulator is required for benzene tube calibrations.) The
span gas concentration should be chosen to be near the highest concentration of actual
measurements expected. It is also preferred to use the same balance gas (e.g., air or nitrogen) as
occurs in the actual measurements.
To perform a Span calibration, connect the calibration adapter to the inlet port of the instrument,
and connect the tubing to the regulator or gas bag. Select ‘Span Calib’ by pressing the Right key to
enter the submenu. If in Tube Mode, enter the temperature, insert a tube and press Right. The
message ‘Please Apply Gas’ is displayed. Start the gas supply and by press the Up key to begin a
30-second span calibration countdown. The calibration will also start automatically without
pressing the Up key if a high enough gas concentration is detected.
Note:
To abort the Span calibration, press the Left key at any time during the process.
When Span 1 calibration is complete, a message similar to this is
displayed (the value is an example only):
3-Point Calibration
If ‘3-Point Cal.’ is enabled (see Monitor Setup), proceed to perform Span 2 in the same manner as
for Span 1. 3-Point calibration should be used whenever enhanced accuracy is required. It is
especially recommended for measurements above about 500 ppm, where response is not as linear.
Set Calibration Gas
In the Set Cal. Gas menu, select the calibration gas from either the mPower Gas Library or the
user’s Custom Gases list. Custom Gas names and parameters can only be set up through the
mPower Suite software.
This menu is omitted from Benzene Mode because it is always benzene.
Calibration
Zero Calib
Span Calib
Set Cal. Gas
Set Span Value
Set Span 2 Value
Set Cal. Gas
Gas Library
Custom Gases
Span 1 is done!
Reading = 5.00 ppm
Up
Current Temp.
+
2 5 °C
×
Up
VOC Mode
Right
Please Insert Tube
Press Right Key
To Start
Please Apply Gas
Benzene
5 ppm
Calibrating
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