• For gaseous measurements: %/ppm (by volume), % (by volume), kPa/Pa, kPa, bar/mbar, bar,
bar20/mbar20 or bar20
• The Liquid medium for dissolved gas concentration measurements: Water, Beer, Cola or Wine
• The Temperature units for display: °C or °F
Membrane selection
Membrane 29561A is the only membrane valid for CO
gas measurement with this analyzer. To
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ensure the analyzer is correctly configured, choose Configuration, Membrane to bring up the box
which reveals the membrane models available.
Membrane 29561A should be the only membrane available for selection. Select this membrane and
click on OK.
Automatic data acquisition - Setting sampling intervals
The instrument can perform as a standalone data acquisition device, automatically recording gas
measurements with the date and time, and storing up to 500 of these values. Choosing the Hach
3658 program's Configuration, Sampling Rate menu lets you select time intervals (acquisition rate)
for this storage capability.
Use the slide bar to view and select a sampling rate, from 15 seconds to 1 hour. The selected rate is
shown in the Acquisition rate window. Click OK to save this rate. Once your choice is made, the
instrument can be used independently of the Hach 3658 program for data acquisition. Refer to
Automatic data acquisition
on page 11.
Note: The Acquisition rate set via this menu is independent from the monitoring chart updating rate in
Monitoring
measurements in real-time
on page 13. The sampling rate menu applies only to automatic data acquisition, while
the chart updating rate is used only for displaying real-time results via the monitoring chart.
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.
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.
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.
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.
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.
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