Hanna Instruments HI 98713 User Manual

Page 13

• At the end of the measurement, the third

calibration point (100 FNU) is displayed on
the primary LCD, “CAL P.3” on the secondary
LCD, and “READ” tag will blink.

• At this moment it is possible to exit calibration

by pressing CAL. The instrument will memorize
the two-point calibration data and will return
to measurement mode.

THREE-POINT CALIBRATION
To perform a three-point calibration, continue the
procedure with the following steps:

• Remove the second standard cuvet.

• Place the 100 FNU standard cuvet (or the

prepared formazin standard) into the holder,
with the cuvet mark aligned with the sign on
the instrument.

• Close the lid and press READ . The display will

show blinking dashes and the icons for cuvet,
detectors and LED will appear during measurement.

• At the end of the measurement, the fourth

calibration point (750 FNU) is displayed on the
primary LCD and “CAL P.4” on the secondary LCD.

• At this moment it is possible to exit calibration

by pressing CAL. The instrument will memorize
the three-point calibration data and will return
to measurement mode.

FOUR-POINT CALIBRATION
To perform a four-point calibration, continue the
procedure with the following steps:

• Remove the third standard cuvet.

• Place the 750 FNU standard cuvet (or the prepared

formazin standard) into the holder, with the cuvet
mark aligned with the sign on the instrument.

OUT CAL RANGE FUNCTION
The instrument has an

Out Cal Range function to

prevent taking measurements in a range where the
calibration does not assure the best results. The range
where the calibration assures correct measurements is
up to 40 FNU for two-point calibration and up to 150%
of the third point value for three-point calibration.
The display will show a blinking “CAL” tag each time the
measurements are taken outside the calibration range.

CALIBRATION ERRORS
• If the read value during calibration is too far

from the set value, the instrument will show
“-LO-” or “-HI-” error.

• If the calculated calibration coefficients are outside

a certain range, the “CAL Err” message is displayed.

CALIBRATION DELETION
HI 98713 is factory calibrated. It is possible to delete
last performed calibration.
To delete last calibration, follow the next steps:
• Enter the GLP feature by pressing GLP .

The date of the last calibration will be displayed
on the LCD.

• Press READ to see the information related to

calibration. The last panel is the one with delete
calibration.

• Press SETUP/DEL to delete the current calibration.

After deletion the instrument will automatically
return to measurement mode.

• Close the lid and press READ . The display

will show blinking dashes and the icons for
cuvet, detectors and LED will appear during
measurement.

• At the end of the measurement, the four-point

calibration is completed and the instrument
returns automatically to measurement mode.