Ametek mocon Dansensor ISM-3, Руководство пользователя

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Dansensor
®
ISM-3 EN User Manual 19
P/N 200114-I
09/2021
6. Calibration
Besides atmospheric air, you can calibrate with up to 4 calibration gases. If an offset
adjustment has been made after the last calibration, a calibration of ISM-3 must always be
started from the beginning again, meaning that calibration with 20.946% O
2
must be carried
out initially. If an off set adjustment has been made and calibration is attempted with another
gas than 20.946% O
2
the error message
ER.8
will appear (cannot calibrate after the offset
adjustment).
When calibrating with 20.946% O
2
the result is compared with the latest 20.946% O
2
calibration. All other calibrations are adjusted using the difference between the new and the
preceding 20.946% O
2
calibration. If an offset adjustment has been carried out, it is reset. After
the calibration with 20.946% O
2
, calibration must be performed with the selected calibration
gases. See below.
The device is factory calibrated by default to perform O
2
measurements in the range of 20.9%
to 1ppm using calibration gasses of 20.9%, 1%, 1000ppm, 100ppm, and 25ppm respectively.
If you want to measure on gasses up to 100%, the device must be re-calibrated with a gas of
min. 80% O
2
replacing the 25ppm calibration.
New measuring range of the device will hereafter be 100% - 100ppm.
If you want to measure on gasses below 20.9% O
2
we recommend that you calibrate the
device with minimum 2 gases (besides 20.9%), one above and one below the range in which
you want to measure.
Calibration
NOTE! ISM-3 must warm up for at least 1 hour before making the calibration.
The following procedure must be used in order to calibrate ISM-3:
1. Before the calibration is started, it must be assured that the measurement can be started
via the

button and that the measurement cannot be started/ stopped via an external
measurement control signal during the calibration. You can choose manual start/stop
measurement alone, by setting the first digit in the
PA
parameter in the set-up menu to
"
0 - - -
". Make a note of the setting before making the change.
2. If ISM-3 is not equipped with an internal pump: Connect the calibration gas to gas in and
adjust the input pressure in order to produce a flow of 125±5ml/min.
If ISM-3 is equipped with an internal pump: Establish a gas overflow of approx. 0.5 l/min
(hose with inner diameter of min. 3 mm) and let ISM-3 suck the calibration gas from here.
See illustration on
page 28 for details.
3. Start the measurement with

.
4. Let ISM-3 measure on the gas for at least 4 minutes. When calibrating with gases of less
than 1000ppm it is recommended to measure for about 10 minutes. Then check that the
output of O
2
in the display is stable for about 1 minute before carrying out the calibration.
When the output is stable check that the output O
2
value corresponds to or is very close to
the analysis value of the calibration gas. If this is not the case, check for leaks in the
measurement gas hose and for a sufficient gas supply pressure.