Hach NT3100sc Manual Del Usuario página 16

Option Description
Factor Enters a slope factor to adjust the standard calibration.
Options: from 0.8 to 1.2 (default: 1)
Note: Use grab samples with known values or standard solutions to determine the slope
factor.
Standard Start calibration—Starts a one-point calibration.
calibration
Standard value—Selects the value for the calibration standard.
Note: The Standard calibration option is not available if matrix calibration is active.
Calibration Sets the calibration interval. Options: off (default), 1 week, 4 weeks, 3 months or 6 months.
interval Note: Not available if matrix calibration is active.
5.3.2 Matrix calibration
The matrix calibration is available for the NT3200 probe only. The matrix calibration adapts the
calculation for the two parameters to the conditions in the medium. A matrix calibration is based on a
laboratory comparison measurement. Start the matrix calibration after the probe is in the medium and
has adapted to the environment. Wait a minimum of 15 minutes with the default configuration
settings to let the probe adjust to the temperature, complete some wiping cycles to clean the
measurement gap and remove air bubbles.
In general, a matrix calibration is necessary to adjust the measurements to the background
environment. An error message also gives an indication that a matrix calibration is necessary
because of a possible seasonal medium change or a process change.
Note: Doing or erasing a matrix calibration does not have an effect on the factory calibration.
For optimal matrix calibration:
• Collect the grab sample, then immediately validate on the controller that the grab sample was
collected.
• Collect the sample as near as possible to the sensor.
• Start the matrix calibration only when the concentrations are stable.
• To measure the grab sample, refer to
1. Go to the main menu, then select Calibration > Matrix calibration > Start matrix calibration.
2. Immediately follow the instructions on the controller to collect a grab sample. Validate the
message immediately after the grab sample is collected. Prepare the grab sample (e.g., filtration)
as soon as possible for laboratory measurement.
Note: The measurement data is initially saved on the controller for the probe, then adjusted when the
laboratory values are determined and entered.
3. Measure the grab sample in the laboratory with the two parameters: NO
and NO .
2
4. Select Calibration > Matrix calibration > Enter lab values.
Note: The Enter lab values option only shows when the Matrix calibration is started.
Note: Make sure that the chemical formulas of the sensor and laboratory measurements are the same (e.g.,
NO –N and NO –N or NO
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5. Enter the laboratory values.
6. Select Calibration > Matrix calibration > Information.
Information about the current matrix calibration shows.
7. Select Calibration > Matrix calibration > Calibration interval to set a reminder for the Matrix
calibration.
If necessary, go back to the factory calibration. Select Calibration > Matrix calibration > Reset to
default.
16 English
Instructions for laboratory measurements
and NO ).
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on page 25.
–N and NO –N or NO
3 2 3