Aquaprobe
®
AP-700, AP-800 & AP-2000 Instruction Manual
10401-00870 Rev R
7.
Select ZERO. The screen will change to:
PLEASE WAIT
Stabilising
000%
The Meter will wait until the readings are stable, then it will send the calibration command
to the Probe, where the calibration takes place. During calibration, the Calibrating screen is
displayed and the progress counter counts up. If the calibration is successful, the counter
will reach 100% and the following screen will be displayed.
Output:2500mV
Calibrating
100%
Press [OK]
The Calibration Report on the top line displays the voltage output from the electrode in
millivolts (mV). This value is stored in the Probe's memory and can be recalled at any time.
See section
10.7 Calibration Data Storage and Retrieval
. Press
OK
then
ESC
repeatedly
to return to normal reading mode
.
16.6.7.
Calibrating Point 2
Remove the Probe from the calibration bottle, shake off any excess water then dry the
outer sleeve with a soft cloth.
Fill a calibration bottle with freshly mixed Rhodamine calibration solution and drop the
Probe in all the way. Again, bang the Probe against the bottom of the bottle several times in
order to remove any air bubbles that may be clinging to the electrode.
Follow the procedure detailed above for Zero point calibration as far as step 6, then select
Pt-2. Wait while the Meter stabilises and calibrates.
After successful calibration, the ‘Calibrating 100%’ screen will be displayed along with the
Calibration Report, which will show the voltage output from the electrode in millivolts (mV).
Press the
OK
key to continue. The reading on the Aquameter
®
directly after calibration
should be approximately 200,000 cells/mL at 20ºC (this value will vary with temperature).
Calibration is now complete.
16.6.8.
Calculating and Applying a Grab Sample Factor
The Grab Sample Factor (GS Factor) is a value that is used as a multiplier to correct the
readings made by a fluorescent electrode based on known values derived from grab
samples. The default GS factor is 1.00. So when the electrode's output is multiplied by a
GS Factor of 1.00, the value is not affected.
If grab sample data is available for the location in which you plan to take measurements,
you should calculate a GS Factor for the electrode and input it on the bottom line of the
electrode's calibration screen.
To calculate a GS Factor, first take measurements using the fully calibrated electrode.
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®
Ltd.
www.aquaread.com
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