Hach NO3D sc, User Manual

Page: 27 / 48

27
Operation
4.6.3.5 Value correction
Value correction offers the option of subsequently correcting a
matrix at two different concentrations.
Take several samples on various days with different concentrations
and perform an analysis of the samples in the laboratory.
Note: The concentrations should be in a concentration range of at least
half a decade.
1. Note the two displayed nitrate and chloride values, which are
measured with the sensor at the time of the sampling.
2. Then note the measured nitrate laboratory reference value.
All 3 values are one correction point.
3. From the values recorded, select the two correction points with
nitrate concentrations as far apart as possible.
4. Select
CAL CONFIG.> CALIBRATE>VALUE CORR
from the menu
and press
ENTER
to confirm.
Enter the 3 noted values:
5. 1. NO3–N NO3D sc: Enter the displayed NO
3
–N value for the
1st correction point. Press
ENTER
to confirm.
6. 1. CL- NO3D sc: Enter the displayed Cl
−
value for the 1st
correction point. Press
ENTER
to confirm.
7. 1. NO3–N lab: Enter the measured NO
3
–N laboratory
reference value for the 1st correction point. Press
ENTER
to
confirm.
8. 2. NO3–N NO3D sc: Enter the displayed NO
3
–N value for the
2nd correction point. Press
ENTER
to confirm.
9. 2. CL- NO3D sc: Enter the displayed Cl
-
value for the 2nd
correction point. Press
ENTER
to confirm.
10. 2. NO3–N lab: Enter the measured NO
3
–N laboratory
reference value for the 2nd correction point. Press
ENTER
to
confirm.
Value correction is activated and displayed as
MATX2
.
Conc2
Conc1 10
×
2
-------------------------------
=