TM 10-4610-310-14
0005 00
TURBIDITY METER OPERATION - continued
2. The infrared light source used for the HI 93703 turbidity meter, or equal, according to International Standard
Organization (ISO) 7027, can effectively minimize errors due to colored dissolved substances. This effect,
called "true color", is a common interference for most commercially available instruments operating in the
range of visible light.
3. Air bubbles and the effect of vibrations that disturb the surface of the sample will give false results.
4. Dirty glassware could affect readings along with scratched or edged cuvets.
Viewing the Calibration Date
1. Turn the turbidity meter on. Press ON/OFF key to ON. Pause for the instrument display to show " - - - -".
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2. Press and hold the DATE/⇒ key. A "MM.DD" message will appear while the key is held.
09.02 DATE
NOTE
The displayed date is the date that was input by the operator at the beginning of the last calibration.
Automatic Shut Off
The turbidity meter is equipped with an automatic shut off function that turns the meter off after 4
minutes of nonuse. The power source is four 1.5V AA batteries with an expected life of 60 hours or over
900 measurements. The batteries are monitored to ensure that readings are not taken when there is
insufficient power.
Two indications on the turbidity meter will inform the operator that the batteries require replacement:
LO BAT indication appears on the lower right hand side of the display when the batteries are weak
and require replacement. At this point the meter is able to perform only 50 more measurements. See
error codes.
-BA- - indication appears on the display when the batteries are too weak to perform measurements; the
message appears for a few seconds, and then the meter will automatically switch off. At this point, it is
absolutely necessary to replace the batteries to use the meter. See error codes.
Liquid Crystal Display and Error Codes
Turbidity meter HI 93703 will display several different LCD codes in different situations to help the user to
operate the meter. The following data illustrates the display on the LCD:
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This indicates that the meter is in a ready state and measurement or calibration can be preformed.
CAL
0005 00-4
