Hanna Instruments LP 2000-11 - Manual (Page 8)

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• Place the 0.00 FTU standard in the cuvet
holder.
• Press CAL; SIP and CL will start blinking.
• If “ERR1” appears on the LCD, please check
the standard solution.
• After approximately 30 seconds the meter
will display “10.00”, prompting the user
to place the 10.00 FTU standard solution
in the cuvet holder.
• Place the 10.00 FTU standard in the
holder and press CAL. SIP and CL will start
blinking.
• After approximately 30 seconds the meter
will display 500, asking the user to place
the 500 FTU standard solution in the cuvet
holder.
Note: At this point the user can save the two-point calibration setup
and leave the calibration mode by pressing ALT & CAL buttons.
err1
CALIBRATION
SOURCES OF INTERFERENCE
• The presence of floating debris and coarse sediments which may
settle out rapidly will give false readings.
• The infrared light source of LP2000-11 turbidity meter complies
with the ISO 7027 International Standard and 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.
• Air bubbles and the effect of vibrations that disturb the surface of
the sample may produce false results and should be avoided.
• Dirty, scratched, or etched glassware could also affect readings.
To check the date of last calibration, simply press the GLP key. Press again
to toggle between date and time.
To make sure that the meter is calibrated, take a measurement of a
standard solution.
The instrument can be calibrated at two or three points and a monthly
calibration is recommended.
CALIBRATION PROCEDURE
• Turn the meter on and wait for the display
to show "----".
• Press the ALT & CAL buttons. The "CAL" message will blink on the display
for 3 seconds. The meter then enters the calibration mode, displaying
"0.00" and prompting the user to insert the 0.00 FTU standard.