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3. Conductivity (TDS/Salinity) Calibration
To achieve accurate Conductivity/TDS/Salinity results, the
Aqua-CPA
requires calibration to an allowable Conductivity standard. The TDS and
Salinity values are derived from the Conductivity reading and do not
require a separate calibration. The conductivity of a solution varies with
temperature.
The
Aqua-CPA
uses
Automatic
Temperature
Compensation (ATC) referenced to the fixed temperature of 25
o
C.
A “
∗
” in place of the decimal point indicates that the Conductivity or TDS
or Salinity readout is not calibrated, or a past calibration has failed. The “
∗
” will be removed once a Conductivity calibration has been successfully
performed in Conductivity standard.
3.1 Calibration Procedure
1. Switch the
Aqua-CPA
on.
2. Select a display mode showing Conductivity or TDS or Salinity readout
(section 0).
3. Plug the Conductivity sensor into the sensor socket. If a k=10 or k=0.1
sensor is being used, ensure that it has been correctly selected (see
section 6).
4. Rinse the Conductivity sensor in distilled water. Shake off as much
water as possible. Blot the outside of the sensor dry. DO NOT BLOT
THE SENSOR WIRES.
Zero Calibration
5. Let the sensor dry in air.
6. When the reading has stabilised at or near zero, press the
key.
The
Aqua-CPA
will prompt the user to select the parameter if a
combination display is shown. Use the
or
keys to select
Conductivity.
The display will change to Conductivity during calibration if the
Aqua-
CPA
is in TDS or Salinity Mode.
A “
∗∗∗∗
” will not be removed after a zero calibration.