Hach-Lange ORBISPHERE 3650 - Manual (Page 41)

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Options Setup
5.4.4 Locking out the instrument’s CAL button
You can use the Configuration, Calibration Key Status menu to prevent an accidental sensor
re-calibration from the instrument keyboard.
5.4.5 Sensor calibration range checking
When calibration is performed for In Air and In a Span Gas calibration modes, the sensor
measurement current is compared to an ideal current for the selected membrane to determine
whether or not to complete the calibration. You can use the Configuration, Calibration Range
Checking
menu to enable or disable sensor calibration range checking in the instrument.
Choose Disabled to calibrate without checking the value of the measurement current, within a
range of 0% to 999% of the ideal current.
When set to Enabled, at calibration the measurement current should be between 25% and
175% of the ideal current; if the value is outside of these limits, the calibration fails and Err is
displayed on the instrument LCD. Choose OK when the desired mode is selected.
Note: It is recommended to leave range checking enabled. In special measurement situations it may be
necessary to disable range checking. However, contact a Hach Lange representative for further details
before disabling this feature.
5.4.6 Entering a span gas value
When calibrating the sensor in a span gas, use the Configuration, Span Gas menu to enter the
concentration of the gas to be measured in the span gas.
Choose Disabled to lock out the keyboard CAL button. To
unlock this capability, choose Enabled.
Choose OK when the desired mode is selected.
Enter the percentage of measurement gas in the span gas
(e.g. 10.00%), then choose OK.