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3. Conductivity Calibration
3.1 Calibration Procedure
1.
NOTE 1
: A
∗
in place of a decimal point indicates the mode is not calibrated.
2.
NOTE 2
: For correct calibration and measurement, the white plastic cover
must be in place covering the cell. It sets the volume of liquid to be measured.
3.
Press the
key if the meter is not already switched on.
4.
Press the
key until the meter is in Conductivity mode (see section 2.2).
5.
Plug the Conductivity electrode into the
Cond
socket.
6.
Rinse the Conductivity electrode in distilled water.
Shake off as much water as possible. Blot the outside of the electrode dry.
DO NOT BLOT THE ELECTRODE WIRES.
7.
Zero Calibration
Let the electrode dry in air.
When the reading has stabilised at or near zero, press and hold the
key for
2 seconds.
The
∗
will not be removed after a zero calibration.
8.
Standard Calibration
Allowable Conductivity standards are 2.76mS/cm for the standard k=1
electrode and 2.8mS/cm & 58.0mS/cm for the optional k=10 electrode. The
standard should be selected according to your range of interest.
Place the electrode into a sample of Conductivity standard, so that it is
immersed at least to the vent hole in the white plastic cover. The white plastic
cover MUST be in place for correct readings.
DO NOT
place the electrode directly into the bottle of standard. Discard the
used sample of standard after use. It is advisable to use a narrow sample
vessel to minimise the use of standard solution.
When the reading has stabilised, press and hold the
key for 2 seconds to
calibrate.
The
∗
will now be replaced by a decimal point, if calibration was successful.
9.
The
MC-81
is now calibrated for Conductivity and is ready for use. When
taking sample measurements, the white plastic cover MUST be in place for
correct readings. The electrode must be immersed at least to the level of the
vent hole in the cover.