YSI IQ S ENSOR N ET TriOxmatic 702 IQ - Manual (Page 17)

TriOxmatic
®
702 IQ Measuring / Operation
4 - 1 ba76048e01 01/2012
4 Measuring / Operation
4.1 Measuring
4.2 Calibration
4.2.1 General information on calibration
Why calibrate? During the operation of a D.O. sensor, the slope of the D.O. sensor
changes with time. The calibration procedure determines the current
slope of the sensor.
When to calibrate? Calibrate before measuring and at regular intervals (depending on the
application).
Calibration procedures Ideally, calibration takes place in water vapor-saturated air. To do so,
position the sensor approx. 2 cm above a water surface, for example in
a narrow bucket or similar container with water.
In the case of air temperatures under 5 °C we recommend to calibrate
not in air but in air-saturated water that has a higher temperature. You
obtain air-saturated water by pouring water several times in and out of
two vessels so that it sparkles.
Calibration log The calibration history contains the calibration log of the current and the
last calibration. You can call up the calibration reports for the sensor via
the Calibration history display option.
Note
For calibration the membrane always has to be clean, for calibration in
air it has to be dry. Clean contaminated sensors before calibration (see
section 5.2 C
LEANING THE SENSOR SHAFT AND MEMBRANE ).
Maintenance condition During calibration the sensor is in the so-called maintenance condition.
This means all linked outputs retain their momentary state. After
finishing calibration the maintenance condition has to be switched off
manually. For more detailed information on the maintenance condition
please refer to the respective IQ S
ENSOR N ET system operating
manual.
1 Install the sensor in the D 702/N flow-thru vessel (see
operating manual of the flow-thru vessel) and put it into
operation with the measuring medium.
2 Read the measured value on the terminal of the IQ S ENSOR
N ET system.