Matrix Correction Overview - Hach NO3D sc User Manual

4.6.2 Matrix correction overview

Correction Option Application
The most commonly used Matrix correction. It performs a 1 point matrix correction (offset
MATX1
adjustment) for nitrate
With the MATX1 CL- the nitrate value will be corrected as with the MATX1 and in addition the
MATX1 CL- chloride value can be corrected. This is necessary if a higher precision of the nitrate value is required
as the chloride value will interfere with the nitrate measurement
Where there is a dynamic process with a large nitrate fluctuation (at least 1/2 decade between the
MATX2
lowest and highest concentration)
Where there is a dynamic process with a large nitrate fluctuation (at least 1/2 decade between the
MATX2 CL- lowest and highest concentration)
perform the MATX2 CL-
The nitrate and chloride displayed value and the nitrate laboratory value can be entered for two
VALUE CORR points. This is a different way to perform a MATX2 Correction. Here, for two points, the displayed
nitrate and chloride values and the nitrate laboratory value are entered via an input screen.
PREVIOUS CAL Activation of one of the last 4 matrix and value corrections performed.
If the current sensor code is no longer available, average data for the sensor can be activated using
FACTORY CAL
FACTORY CAL.
1
Examples of a half decade: The nitrate nitrogen concentration moves between 1 and 5 mg NO
between 5 and 25 mg/L NO
which includes a multi-point nitrate and chloride calibration and the
cross sensitivity of chloride on nitrate.
When the code is entered, the sensor is completely calibrated. It is
recommended to perform a matrix correction to correct the
cartridge on the specific matrix.
Please use the default sensor code, if the specific sensor code is
not available.
To change the sensor code:
1. Select
2. Enter the 16 character sensor code.
3. Press
All old calibration data are now overwritten with the new calibration
data from the sensor code. The sensor code data are checked by
the system. If an error is indicated, check the sensor code and
repeat the entry of the sensor code if necessary.
With the NO3D sc sensor, there are various options
correcting the measured value with laboratory reference values.
For the laboratory reference value, a sample is taken for laboratory
analysis and the measurement value at that time is stored.
Depending on the parameter set, the laboratory reference value of
the water sample is stored as nitrate nitrogen (NO
(NO
measured by the sensor.
Table 1 Correction options for the NO3D sc sensor
(4.6.3.1 on page
(4.6.3.4 on page
–N ( Conc 2 = (Conc 1 x 10)/2 ).
3
SENSOR SETUP>NO3D SC>
CALIBRATE>CAL.CONFIG.>SENSORCODE
to confirm and activate the sensor code.
ENTER
The day meter is set to zero.
). This laboratory reference value replaces the prior value
3
24).
1
, it is recommended to perform the MATX2
1
and chloride value is to be corrected, it is recommended to
26).
Operation
(Table
–N) or as nitrate
3
(4.6.3.2 on page 24).
(4.6.3.3 on page
–N or
3
1) for
25).
23