Hanna Instruments c 114 User Manual

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Using  ,  , 

 keys set

the lower part to “d 31”.

Insert the previously prepared deionized wa-
ter standard into the cuvet holder and make
sure that the notch on the cap is positioned
securely into the groove. Press the 

 key.

The display will blink
“-Lc-” for several sec-
onds, indicating that
adjustment of the LED
for the colorimetric measurements is in
progress.

After this, a sequence of numbers between
-511 to 512 will appear on the upper LCD
indicating the different levels of LED light
intensity. In approximately one minute, the
adjustment will be made and the calibration
data will be stored in the non-volatile memory.

Display will show four
dashes again indicating
the end of the zero cali-
bration procedure.

Press the ALT and CAL
keys again to leave the
diagnostic mode.

Two-point customized calibration

To enter the colorimetric calibration mode, press
momentarily both the ALT and CAL keys. The
LCD will show four dashes and “d00”.

After the second calibration point is memo-
rized, the unit will store the calibration data
together with time and date in the EEPROM
while intermittently indicating “CAL” and “Stor”
for several seconds.

Subsequently, the up-
per display will show
“----”, indicating that the
meter is calibrated and
ready to measure turbidity of an unknown
sample.

By pressing CAL during calibration,
user can quit the calibration mode
at any time without changing the
previously stored calibration data.

Zero calibration

To calibrate the span of the meter, fill the
cuvet with a clean deionized water sample.
Inspect and thoroughly clean the surface of
the vial.

Turn the meter on and press both ALT and
CAL momentarily.

The display will show
four dashes and “d 00”.
The second “0” will blink
to allow the user to
make a selection.