Hach 900 MAX ユーザーズマニュアル

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Section 5
Page 77
8990options.fm
Conductivity Probe
5.5.4 Conductivity Probe Calibration
1.
From the Main Menu, select 
OPTIONS > ADVANCED OPTIONS > 
CALIBRATION > CONDUCTIVITY.
2.
Clean and dry the probe.
3.
Place the sensor and thermometer in the calibration solution 
(Cat. No. 3230). The temperature sensor is located in the middle of the 
sensor body allowing the probe to be completely submerged in 
the solution.
4.
Allow the sensor to stabilize in the solution about 10 minutes to ensure 
that the probe and the solution are the same temperature.
5.
Enter the temperature correction factor or enter zero for no correction 
factor. 
Note: The temperature correction factor is used to compensate for the effects of 
temperature on the conductivity readings at the point of installation. The 
conductivity of a solution is temperature sensitive. Therefore the actual 
conductivity of the solution will change with the temperature. Each site may have a 
different correction factor depending on the major constituent of the flow stream. 
This is not used for calibration and has no effect on the calibration of the sensor. 
Below are some examples of compensation factors of various liquids.
0.96%/°C 5% Sulfuric Acid
1.88%/°C Dilute Ammonia
1.91%/°C ‘Typical’ Wastewater
1.97%/°C Potassium Chloride 
2.12%/°C Salt (Sodium Chloride)
2.84%/°C 98% Sulfuric Acid
4.55%/°C Ultra-pure Water
6.
With the sensor still in the calibration solution, press any key. Wait for the 
sensor to stabilize. Calculate the actual conductivity of the calibration 
solution. If using the KCl solution provided by the manufacturer, make 
your selection from the 
. If using a solution other than 
1.0 mS @ 25 °C KCl available from manufacturer, calculate the 
conductivity of the solution using temperature correction factors. See the 
following example.
Example: The KCl calibration solution is 1.0 mS at 25°C. If the actual 
temperature of the KCl at the time of calibration is 18.4 °C, then the solution 
has a conductivity value of 0.870 mS. 
a.
Find the difference between the labeled temperature and the actual 
temperature of the calibration solution at the time of calibration. 
25 °C – 18.4 °C = 6.6 °C
b. Multiply the difference (6.6) by the correction factor per °C (1.97% or 
0.0197).
6.6 °C x 0.0197/°C = 0.13002