Hanna Instruments HI 96701C - Manual (Page 15)

15
VALIDATION PROCEDURE
Oxidized Manganese and Chromium (positive error)
Chlorine dioxide (positive error)
Alkalinity above 250 mg/L CaCO
3
or acidity above 150 mg/L CaCO
3
will not reliably develop the
full amount of color or it may rapidly fade. To resolve this, neutralize the sample with diluted
HCl or NaOH.
In case of water with hardness greater than 500 mg/L CaCO
3
, shake the sample for approximately
2 minutes after adding the powder reagent.
Use the validation procedure to ensure that the instrument is properly calibrated.
Warning:
Do not validate the instrument with any standard solutions other than the HANNA CAL
CHECK TM Standards, otherwise erroneous results will be obtained.
• Turn the meter on by pressing ON/OFF.
• When the beeper sounds briefly and the
LCD displays dashes, the meter is ready.
• Place the CAL CHECK TM Standard
HI 96701-11 Cuvette A into the cuvette
holder and ensure that the notch on the
cap is positioned securely into the groove.
• Press ZERO/CFM and the lamp, cuvette
and detector icons will appear on the
display, depending on the measurement
phase.