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MW190 Dissolved Oxygen & Temperature Bench Meter
9. CALIBRATION
Ensure the probe is ready for measurements. Follow the procedure in PROBE PREPARATION
section.
y
Set the appropriate altitude and salinity compensation value (see SETUP OPTIONS
section).
y
For highest accuracy, complete all calibrations at a temperature as close as possible
to the sample temperature.
y
For an accurate calibration, it is recommended to wait for at least 15 minutes to ensure
precise conditioning of the probe.
y
Keep the protective cap on during polarization time and remove it for calibration and
measurements.
The
MW190
accepts two % saturation calibration points; 100% using saturated air and 0%
using zero oxygen solution. For most applications, air calibration is sufficient.
The meter should be recalibrated:
y
Whenever the probe is replaced
y
When high accuracy is required
y
If “CAL EXPIRED” or “NO CAL” is displayed
y
At least once a week
100% Saturated Calibration
The 100% calibration is performed in water-saturated air.
1. Pour water into a small beaker. Rinse the polarized probe with clean water.
2. Dry the probe tip and allow a few seconds for the LCD reading to stabilize (probe in air).
3. Hold the probe in air over the beaker. Avoid any contact of the membrane with water.
4. Press CAL/EDIT to enter calibration.
LCD displays 100.0% with “WAIT” (blinking) and hourglass symbol until the reading
is stable. When the reading is stable and within the limits, LCD displays “STD” with
ACCEPT tag (blinking).
5. Press GLP/ACCEPT key to confirm.
LCD displays “0.0%” calibration point and “WAIT” (blinking).
6. Press CAL/EDIT. LCD displays “SAVING”, stores the calibration value and returns to
Measurement mode.
