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Note: calibration indication icons are examples of Standard series.
7.2.2 Calibration frequency
(a) The meter is calibrated before leaving the factory and can generally be used right out of the box.
(b) Normally, performing calibration once a month is recommended.
(c) For high accuracy measurement or larger temperature deviation from the reference temperature
(25°C), performing calibration once a week is recommended.
(d) Use conductivity standard solution to check the probe. Perform calibration if the error is significant.
(e) When using a new probe for the first time, or the meter has restored to factory default setting, 3-
point or 4-point calibration is recommended. For everyday use, standard solution closer to the
sample solution can be chosen to perform 1- point or 2-point calibration. For example: 1413 μS/cm
standard solution is suitable for measuring range 0-20mS/cm.
7.2.3 Reference temperature
Factory set reference temperature is 25°C. Other reference temperature can also be set within the
range 15°C~30°C. Set up reference temperature in parameter setting clause 2.4
7.2.4 Temperature coefficient
Factory set temperature compensation coefficient of the meter is 2.0%. However, the conductivity
temperature coefficient is different from that of varous kinds of solution and concentration. Please refer
to chart – 7 and the data collected during testing and set up the parameter in clause 2.5.
Note: When the temperature compensation coefficient is set to 0.00 , it means there is no
temperature compensation. The measurment value will be based on the current temperature.
Chart -7 Temperature compensation coefficient of certain solutions
Solution
Temperature compensation coefficient
NaCl solution
2.12 %/°C
5% NaOH solution
1.72 %/°C
Dilute ammonia solution
1.88 %/°C
10% hydrochloric acid solution
1.32 %/°C
5% sulfuric acid solution
0.96 %/°C
7.2.5 Avoid contamination of standard solutions
Conductivity standard solution has no buffer. Please avoid contamination during usage. Before
submerging the probe in standard solution, please rinse the probe with purified water and remove
excess water with clean tissue. Please do not use the same cup of conductivity standard solution
frequently, especially for standard solution of low concentration 84μS/cm. The contaminated
standard solution will affect accuracy of measurements.
