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4. For multi-point calibrations, please repeat the steps in 6.3.1 to 6.3.2 until all calibrations are finished. The
meter can be calibrated in the same calibration solution repeatedly until the reading is stable and repeatable.
TDS, Salinity, Resistivity & Conductivity
1.
TDS and conductivity is linear related. The conversion factor is 0.40-1.00. Adjust the factor from parameter P2.6.
The factory default setting is 0.71 and please refer to section 7.4. Salinity and resistivity are all proportional to
conductivity. The calculating formula is preset in the meter. So the meter only needs to be calibrated in
Conductivity mode, then after calibration of conductivity, the meter can switch from conductivity to TDS, salinity,
or resistivity.
2.
Adjust TDS conversion factor in parameter setting P2.6 according to the data collected during testing and
experience. Table – 10 lists some commonly used Conductivity and TDS conversion factors. This is for your
reference only.
Table – 10 Conductivity and TDS conversion factors
Conductivity of solution
TDS conversion factor
0-100 μS/cm
0.60
100-1,000 μS/cm
0.71
1-10 mS/cm
0.81
10-100 mS/cm
0.94
Sample test
1.
Rinse conductivity electrode in distilled or pure water, dry it, and submerge it in the sample solution. Stir the
solution briefly and allow it to stay in the sample solution until a stable reading is reached and
icon appears
on LCD, then get the reading value, which is the conductivity value of the solution.
2.
Press
key to switch to TDS, Salinity, and Resistivity.
3.
During the process of calibration and measurement, the meter has self-diagnosis functions, indicating the
relative information as below: Table – 11.
Table – 11 Self-diagnosis information of conductivity measurement mode
Display Icons
Contents
Checking
Wrong conductivity calibration solution or
the meter recognition of calibration
solution out of range.
1. Check whether conductivity calibration
solution is correct.
2. Check whether the meter connects the
electrode well.
3. Check whether the electrode is damaged.
Press
key when measuring value is not
stable during calibration.
Press
key
after
icon appears.
During calibration, the measuring value
being unstable for over 3 minutes.
1. Shake the electrode to eliminate bubbles in
electrode head.
2. Replace with new conductivity electrode.
Enters pre-set due calibration to remind re-
calibration
Press
key to perform calibration or cancel due
calibration setup in parameter P2.3.
