Delta OHM HD3406.2, User Manual, Page: 15 / 44

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To manually change the compensation temperature press the °C/°F key once: the indicated tempera-
ture value starts blinking. Select the desired temperature value
by using the arrows and confirm with
ENTER. The display stops blinking, and the temperature displayed is used for compensation.
To change the unit of measurement between °C and °F, press the °C/°F key
twice .
Calibration of conductivity
The probe calibration can be carried out on one, two or three points using the standard solutions
automatically detected by the instrument (automatic calibration) or other solutions with known
value (manual calibration).
The CAL symbol will blink when the cell constant is modified using the menu (please see the de-
scription of the K_CELL menu item on page 6).
Automatic calibration of conductivity using memorized standard solutions
The instrument can recognize four standard calibration solutions:
•
0.001 Molar KCl solution (147
μ
S/cm @25°C),
•
0.01 Molar KCl solution (1413
μ
S/cm @25°C),
•
0.1 Molar KCl solution (12880
μ
S/cm @25°C),
•
1 Molar KCl solution (111800
μ
S/cm @25°C),
Using one of these solutions, the calibration is automatic; the procedure can be repeated with one or
more of the remaining standard solutions.
The manual calibration is possible with a different conductivity solution from that used in the auto-
matic calibration.
The solution temperature for the automatic calibration must be between 15°C and 35°C: if
the solution temperature is under 15°C or over 35°C, the calibration is rejected: CAL ERR
indication appears.
1.
Turn the instrument on with the ON/OFF key.
2. Set the probe's cell constant by selecting it from the admitted values: 0.01, 0.1, 0.7, 1.0 o 10.0.
3. Dip the conductivity meter cell in the calibration solution until the electrodes are covered with
liquid.
4. Stir the probe lightly to remove any possible air inside the measurement cell.
5. Press the CAL key. The unit of measurement (
μ
S/cm or mS/cm) appears on the comment line.
The central line shows the solution conductivity value at the measured temperature, or if the