Turner Designs Opti-Trace, Руководство пользователя

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Opti-Trace User’s Manual
Page
12
Measure the Output Current for the Sample
1. Inject a sample of the test solution into the sensor, and note the output current in
Table 1.
Solution Measured Sensor Output Current
Blank Solution Blank Current
Sample Solution Sample Current
2. Flush the sensor through with de-ionized water.
Calculate the Sensor Calibration Coefficient
1. Assume the tracer dye used has a concentration of 30 ppb.
2. Using the current values for the blank and sample, see following table for
example readings, you can calculate the unknown concentration for a known
output current:
Solution Measured Concentration Sensor Output
Current
Blank Solution 0 ppb 4 mA
Sample Solution 30 ppb 19 mA
3. Using the equation for the straight line through the blank and 30 ppb sample,
y = mx + c………. Equation (1)
“y” = sample concentration value
“x” = sensor output value in mA,
“m” is the slope of the response = (sample concentration – blank
concentration)/(sample output current – blank output current),
“c” is a constant equal to the value of “y” when “x” = 0
Table 1