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Parameter
Reset Defaults
ISE Sensor Type
pH
ISE Units
pH
ISE Auto Stable
Off (0.0 % Change
and 10 seconds)
pH Buffer Set
USA
Temperature Units
°C
Pressure Units
mmHg
Language
English
Auto Shutoff
30 minutes
Dissolved Oxygen Calibration
Reset to 100% for enabled
membrane and sensor*
ISE Calibration
Reset to factory default*
Barometer Calibration
Reset to factory default*
*It is recommended to perform a barometer, dissolved oxygen and ISE
calibration after performing a reset.
C A L I B R A T I O N
TEMPERATURE
All Pro1020 cables have built-in temperature sensors. Temperature
calibration is not required nor is it available.
BAROMETER
The barometer in the Pro1020 is calibrated at the factory. The barometer
reading must be accurate to ensure accurate DO% calibrations and
readings. If the barometer requires an adjustment, use the up or down
arrow keys to highlight the barometer box along the bottom of the
Run screen, then press enter. Next, use the up or down arrow keys to
adjust the barometer reading to the local, true barometric pressure.
Continually depress the up or down arrow key to change the barometer
value more rapidly. Press enter to confirm and save the barometer
adjustment.
Do not use a barometer value that is corrected to sea level.
Laboratory barometer readings are usually “true” (uncorrected)
values of air pressure and can be used “as is” for barometer
calibration. Weather service readings are usually not “true”, i.e.,
they are corrected to sea level, and therefore cannot be used
until they are “uncorrected”. An approximate formula for this
“uncorrection” is:
True BP = [Corrected BP] – [2.5 * (Local Altitude in ft above sea level/100)]
Although the Pro1020 barometer range is 400.0 to 999.9 mmHg, you
can not adjust the value across the entire range. The barometer is
very accurate and the instrument will not allow you to adjust the value
drastically beyond what it is measuring.
DISSOLVED OXYGEN
The dissolved oxygen sensor can be easily calibrated with the press
of two keys by enabling Quick DO Cal in the System Setup menu and
following the Quick DO Calibration procedure.
Ensure the barometer is reading accurately before performing a Quick
DO Cal, DO% or DO Local% calibration because these calibration
procedures use the barometer reading during calibration. If the
barometer reading is erroneous during a calibration, the dissolved
oxygen measurements will be inaccurate.
QUICK DO CALIBRATION
Perform this calibration procedure when Quick DO Calibration is
enabled in the System Setup menu.
1. Ensure the DO sensor has a good membrane with electrolyte
installed. A good membrane is free of wrinkles, tears, fouling
and air bubbles. Install the sensor guard onto the probe.
2. Place a small amount of clean water in the calibration/storage
cup and screw it onto the bulkhead. Do not thread it on
completely. Be sure that 2 or 3 threads are disengaged to
ensure the cup is vented to the atmosphere. Additionally, there
should only be little bit of water at the bottom of the calibration
cup. There should not be water droplets or water touching the
DO membrane or temperature sensor.
3. Power the instrument on and, if using a Polarographic sensor,
wait approximately 5 to 15 minutes for the storage cup to
become completely saturated and for the sensor to stabilize.
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