Hach Lange ORBISPHERE 3100, Руководство пользователя

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Main Menu
5.4 Calibration
5.4.1 Barometric sensor calibration
5.4.2 Gas sensor calibration
There are two calibration modes available
• Zero calibration
• High level adjustment
The zero calibration method is the best method to guarantee the sensor specifications.
To get more accurate measurements for samples with higher oxygen concentrations (above 1%
oxygen which corresponds to about 400 ppb dissolved O
2
) a high level adjustment can be
performed using a gas mixture containing 2% oxygen. However, this should not be done without
first ensuring the zero point is accurate (i.e. by performing a zero calibration first).
Zero calibration
High level adjustment
There are three possible modes for high level adjustments:
• Using a reference gas mixture (gas cylinder)
• Using a known oxygen sample (reference sample)
• Enter a factory parameter provided by Hach (this option is only required when the sensor
spot has been replaced)
If the calibration mode displayed is not the required mode, then press the Enter key and select
the required mode from the three options available in the drop-down list:
• Factory parameter
• Reference sample
• Ref. gas bottle
Barometer Calibration
The upper box shows the current barometric pressure as measured by the instrument. Using a precision
certified barometer, measure the barometric pressure in the location where the instrument is used. If the
values differ, enter the correct value in the box provided and select
Validate calibration
O
2
zero calibration
1. Rinse flow path with 20 mL of ethanol (EtOH) using the syringe and connectors supplied in the tool
kit
2. Connect a cylinder of oxygen free gas (minimum 99.999% purity) to the instrument and adjust the
flow to approximately 100 mL/min
3. Let the oxygen free gas run through the instrument for 5 minutes
4. Press the Enter key to start the calibration
5. Wait until the Signal in range and Stability reached fields display Yes which indicates the
calibration is within acceptable limits. The Calibration possible field should also display Yes at this
point. Press the Enter key to complete the calibration
6. Accept ( OK ) or reject ( Cancel ) the new calibration data
O2 high level adjustment - Factory parameter
1. In the Calibration mode window select Factory parameter
2. Scroll down to the Reference value window and enter the factory parameter as found on the
package of the LDO spot (model number DG33218)
3. Scroll down to the Start Calibration window and press the Enter key to start the calibration
4. Accept ( OK ) or reject ( Cancel ) the new calibration data