11
Calibration should be performed daily, before measurements are made, when
the battery has been replaced, between a long series of measurements, or
if environmental changes have occurred since the last calibration.
1. Press the
ON/OFF
key, then release. Two instrument test screens will
be displayed briefly; all LCD segments followed by the percentage of
remaining battery life. The meter will then briefly display an indication
of the measurement units set. When LCD displays dashes, the instrument
is ready.
2. Using a plastic pipette, fill the sample well with distilled or deionized
water. Make sure the prism is completely covered.
CALIBRA
TION PROCEDURE
Note: If the ZERO sample is subject to intense light such as sunlight
or another strong source, cover the sample well with your hand or
other shade during the calibration.
3. Press the
ZERO
key. If no error messages appear, your unit is calibrated.
(For a description of ERROR MESSAGES see page 17).
Note: The 0.0 screen will remain until a sample is measured or the
instrument is turned off.
4. Gently absorb the ZERO water standard with a soft tissue. Use care not
to scratch the prism surface. Dry the surface completely. The instrument
is ready for sample measurement.
Note: If the instrument is turned off the calibration will not be lost.
