Sensor Calibration - Hach ORBISPHERE 3658 Manuel D'utilisation Simplifié

5.4.5 Calibration medium
You can use the Configuration, Calibration medium command to select how the sensor is to be
calibrated.
Choose either in pure CO gas at atmospheric pressure or in a liquid or gaseous solution at a known
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concentration of gas. Choose OK when the desired medium is selected.
Note: Hach Lange recommends the use of its High Precision Calibration Kits for the sensor calibration process.
5.4.6 Wine parameters
Choose Wine Parameters from the Configuration menu to provide a correction for the alcohol and
sugar content of the wine.
This sets two parameters that influence the solubility of CO in wine. This is the degrees of Alcohol
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in the wine, and the concentration of Sugar, in °Brix.
5.4.7 Locking out the instrument's CAL button
You can use the Configuration, Sensor Calibration Status menu to prevent an accidental sensor
recalibration from the instrument keyboard.
Choose Disabled to lock out the keyboard CAL button. To unlock this capability, choose Enabled.
Choose OK when the desired mode is selected.
5.4.8 Rolling average
Choose Rolling Average Status from the Configuration menu to enable or disable the averaging of
gas concentration measurements.
To enable averaging on three successive gas measurements, choose Enable. Choose Disable to
disable rolling average.
5.4.9 Automatic shutdown
Choose Automatic Shutdown Status from the Configuration menu to activate the Automatic
Shutdown feature.
If you select Enable, the instrument switches off automatically after 10 minutes of inactivity, thereby
economizing battery power.
5.4.10 Measurement mode
Choose Measurement Mode from the Configuration menu to enable maximum measurement
mode for sampling in bottles and cans.
In Maximum measurement mode, the instrument searches for two consecutive measurements with
less than a 2% difference, as also described in Measurement mode on page 11. When this occurs,
the display is frozen and you may store the data. The instrument remains in this mode until you
select Normal measurement mode.
Section 6 Calibration
6.1 Barometric pressure sensor calibration
You must have access to an accurate barometer to calibrate the instrument's internal barometric
pressure sensor. This is done using the Hach 3658 program on the PC. Choose Troubleshooting,
Pressure Calibration and a message will warn you that the current calibration will be lost.
Choose OK to continue. The calibration procedure then displays a Pressure Calibration dialog box.
The Measured Pressure value shows the current instrument pressure reading.
Enter the current atmospheric pressure, in mbars, in the Calibration Pressure entry box. Choose
Calibrate to direct the instrument to read and display the Measured Pressure using this calibration
value. Choose Quit when you are satisfied with the pressure calibration to return to normal
operation.

6.2 Sensor calibration

The TC sensor can be calibrated in a liquid sample with a known concentration of dissolved CO , or
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in pure CO gas at atmospheric or elevated pressure. The following table gives information regarding
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the different methods.
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