Teledyne Analytical Instruments LXT-380, Инструкция по эксплуатации

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LXT-380 Universal Transmitter Calibration
Teledyne Analytical Instruments
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4.3.3 STANDARDIZE
Leave the sensor in the process solution, take a grab sample from
the process and determine the Ion concentration.
4.4 SP3X DISSOLVED OXYGEN CALIBRATION
PROCEDURES
The dissolved oxygen AUTO Cal acknowledges zero ppm, mg/l, %
SAT for CAL 1 and the temperature compensated value for atmospheric
oxygen, 8.25 ppm, mg/l at 25°C or 100 % SAT for CAL 2.
The zero point is set by placing the sensor into an oxygen free
solution and verifying the displayed value drops to a value below 1 mV.
The sensor will take a few minutes to equilibrate to the zero oxygen
solution but for the highest accuracy it is best to wait 15-20 minutes
before initiating a calibration. The typical sensor will burn down to 0.5 –
0.7 mV in an hour or so in a zero ppm solution. A zero ppm O
2
solution
can be made by adding approximately 5 grams of sodium sulfite to a
liter of distilled water or purging the sample with nitrogen gas.
The slope (CAL 2) is set by placing the sensor in air saturated
distilled water or water saturated (100% humidity) air. The easiest
method is to suspend the sensor vertically in beaker with a ½” of water
in the bottom slightly above the water.
A STANDardize calibration adjusts the CAL 2 value, resetting the
slope of the sensor, mV/ppm.