Thermo Fisher Scientific CyberScan DO 600 - Manual (Page 109)

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2. DO Calibration in % Saturation Mode (with
ATC)
2.1 About DO(%) and DO (mg/L) Calibration
The calibration of % Saturation of DO will linearly affect the
measurement for DO in mg/L. The amount of oxygen dissolved in water
will depend on its temperature, atmospheric pressure and its salinity. It is
therefore very important that the temperature is calibrated if necessary
prior to the DO calibration.
Hence calibration in % Saturation of DO should be carried out first. This
is described in the following section.
The 600 series meters can be calibrated quickly and easily in air. In %
Saturation, the meter is able to perform either a one point calibration or a
2 point calibration. For one point calibration, it is recommended that you
perform a 100% Saturation calibration in saturated air. If you opt for 2
point calibration, you can calibrate for 100% Saturation in saturated air
and 0% Saturation using a zero oxygen solution.
The meters are capable of measuring barometric pressure with its built-
in pressure sensor. In the event, the pressure reading is inaccurate, you
can calibrate the value from the setup menu.
2.2 To calibrate 100% saturation
1. Switch the meter on and make sure the meter is in % saturation
mode.
2. Hold the probe in the air gently with the sensor facing down and
press CAL (F2) to start calibration.
3. The meter shows the ‘Dissolved O
2
Calibration-Rinse Electrode’
screen for a few seconds to prompt user to rinse electrode with de-
ionized water before calibration.
Note: If the meter is password protected, you will be prompted to enter a
password.