Hanna Instruments HI 98186 - Manual (Page 27)

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TEMPERATURE MEASUREMENTS TEMPERATURE MEASUREMENTS TEMPERATURE MEASUREMENTS TEMPERATURE MEASUREMENTS TEMPERATURE MEASUREMENTS
The DO probe has a built-in temperature sensor.
The measured temperature is indicated on the display.
Allow the probe to reach thermal equilibrium before taking any measure-
ments. This can take several minutes. The greater the difference between the
temperature at which the probe was stored and the temperature of the
sample, the longer the time will be.
Note: If “----” is displayed instead of the measured temperature, the D.O.
probe is not properly connected or the temperature is out of range.
This also indicates the possibility of a broken probe cable.
DO CALIBRATION PROCEDURE DO CALIBRATION PROCEDURE DO CALIBRATION PROCEDURE DO CALIBRATION PROCEDURE DO CALIBRATION PROCEDURE
The following options are available for the Dissolved Oxygen calibration:
•
one point automatic zero calibration at 0% saturation or 0 mg/L
• one point automatic slope calibration at 100% saturation or 8.26 mg/L
• 2 points automatic calibration at 0% saturation (0 mg/L) and 100%
saturation(8.26 mg/L)
• 1 point manual calibration using a standard value set by the user in %
saturation or mg/L
When automatic calibrations are performed it is assumed that the standard
value is the saturated DO value at 25 °C, 0 g/L salinity and 760 mmHg.
When manual calibrations are performed it is assumed that the standard
value is the DO value at the current pressure, temperature and salinity.
Make sure the probe is ready for measurements (see probe connection and
preparation on page 10), i.e. the membrane is filled with electrolyte and the
probe is connected to the meter.
For an accurate calibration, it is recommended to wait for at least 15 minutes
to ensure precise conditioning of the probe.
Remove the protective cap from the D.O. probe.
Make sure the salinity value has been set to the salinity of the standard (see
SETUP for details)
One point automatic zero calibration
Submerge the probe into HI 7040 zero oxygen solution and stir gently for
2-3 minutes.
INITIAL PREPARATION