Aquaprobe
®
Lite Instruction Manual
10401-00976 Rev F
10. About Calibration
Calibration is a very important part of successful water quality measurement and should be
carried out regularly as detailed in the following section of this manual. A great deal of
development work has been put into simplifying and automating the calibration procedures
in the Aquameter
®
in order to allow normal field operatives (as opposed to trained lab
technicians) to achieve quick and accurate results.
The AP-Lite is designed to be calibrated and operated
with the Probe Sleeve and Sleeve
End Cap fitted.
The Probe Sleeve and End Cap form an integral, working part of the Probe’s
measurement system, and MUST be fitted during calibration and measurement for
correct operation.
10.1. Precautions During Calibration
•
Use a non-fluorescent container for calibration solutions.
Some plastics may
fluoresce and interfere with calibration.
•
Use a reasonably deep container for calibration in order to ensure a fast temperature
response. The calibration solution should preferably be up to the blue line on the
Probe. See section 2.2
AP-Lite Minimum and Maximum Insertion Levels
for more
details.
•
Avoid strong artificial lighting during calibration. The alternating nature of artificial
lights (especially fluorescent tubes) can interfere with calibration.
•
Avoid strong sunlight when calibrating the Refined Oil Electrode. The UV in the
sunlight can interfere with calibration.
•
Always be sure that the Probe Sleeve and End Cap are fitted during
calibration.
•
10.2. Calibration Error Messages
If the Aquameter
®
detects a problem with either the AP-Lite or the calibration solution
during the calibration procedure, an error will be indicated. The chart below shows the
possible errors and how to correct them.
Error
Message
Problem
Action
BATTERIES
TOO LOW
Battery Voltage is too low for reliable
calibration
Replace the batteries
NO PROBE
RESPONSE
The Probe is not responding
Check connections / cycle power
READINGS
UNSTABLE
Readings did not stabilise within the
expected period
Top up / replace the calibration
solution. Allow longer for
stabilisation.
OUT OF CAL
RANGE
Readings are outside calibration limits (can
be caused by low level / incorrect calibration
solution). Or the Probe Sleeve is not fitted
Top up / check calibration
solution is correct type. Ensure
the Probe Sleeve is fitted
OUT OF TEMP
RANGE
Temperature is outside 5
°
C – 40
°
C limit
Warm / cool the calibration
solution
CAL ZERO
FIRST
You are trying to calibrate an upper
calibration point on an optical electrode
without first calibrating the zero point.
Calibrate the zero point first,
then without switching the
Aquameter off, calibrate the
upper point.
© 2015 Aquaread
®
Ltd.
www.aquaread.com
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