Sper Scientific LUTU-2016 Turbidity Meter - Manual (Page 13)

Then the LCD display will return to normal
measurement screen, now the meter is finished the
calibration procedures ( 0 NTU, 100 NTU calibration )
completely and ready for the measurement.
8) During the calibration, if exit something wrong
( Error, can not be calibrated....... ), please check
if the " Standard solution " value is wrong, if
still can not fix the problem , then execute the
execute the " Calibration clear " procedures
( Section 6 ) may can fix the problem.
6. CALIBRATION CLEAR
Execute the calibration procedures will clear all the
calibration value ( Section 5 ) , the system will
return to the Default value.
a. Power On ( no matter if the " Testing bottle " insert
into the " Container " or not ) press the " CAL Button "
( 3-5, Fig. 1 ) continuously (at least 3 seconds ) until
the Display show the text " CAL " then release the
button, the display will show :
CAL
Fig. 6-1
ntu
b. After the LCD show above Fig. 6-1, wait a while
the display will show :
0.00
CAL ntu
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