Hach AISE sc, Дополнение к руководству оператора

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English 9
Operation
4.3 Calibration/matrix correction
The four electrodes with the reference system of the compact
sensor cartridge were calibrated with one another at the factory
using special standard solutions (CARTICAL
TM
). However, the
membranes on the ion-selective electrodes are not 100% selective
due to other substances that may affect the measurement. Perform
a matrix correction (refer to
4.3.4, page 11 ) to compensate for other
ions present on the ISE electrodes.
Potassium has the largest interference effect on the ammonium
membrane, while chloride has the largest effect on the nitrate
membrane. The AN-ISE sc probe compensates for this problem
with the aid of a built-in potassium/chloride electrode.
When using the AISE sc probe, only the ammonium membrane and
the integrated potassium electrode are active.
When using the NISE sc probe, only the nitrate membrane and the
integrated chloride electrode are active.
Cross sensitivities between ammonium and potassium/nitrate are
automatically eliminated. Solids do not interfere with the
measurement. Due to matrix effects, correction and validation
cannot be performed with standard solutions. A matrix correction
can be carried out quickly and easily at any time.
4.3.1 Sensor code calibration
The sensor code is a calibration code and is delivered with the
sensor cartridge certificate. It contains the factory calibration
described in
section 3.12, page 9 for the sensor cartridge.
Instruments with automatic sensor code recognition
(LXG440.99.x000x) read this automatically and assume the
Cartrical calibration.
Instruments without automatic sensor code recognition
(LXG440.99.x001x) require the sensor code to be entered during
the initial setup and whenever a new sensor cartridge is activated. If
the sensor code certificate has been lost, carry out factory
calibration (under the sensor code menu) as a temporary solution.
After activating the code, the sensor is fully calibrated but not yet
adapted to the specific matrix of the relevant application on a waste
water treatment plant. At least 12 hours must elapse before a
matrix correction is performed to allow the cartridge to adapt to the
specific matrix.
N O T I C E
A matrix correction may only be performed if the sensor has been
immersed in the corresponding waste water matrix for over 12 hours.
This is the minimum time required to adapt the ISE membranes to the
waste water matrix.