7
CALIBRATION PROCEDURE
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. 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.
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 11).
Note:
The 0.0 screen will remain until a sample is measured or the
power 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.