Hanna Instruments hi 95734 User Manual

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KEYPAD DESCRIPTION
• ON/OFF: to turn the meter on and off.
• ZERO/SET: this is a bi-functional key: press to zero the meter prior to measurement, or hold the
key for 3 seconds to select the desired parameter (free or total chlorine).
• READ/TIMER: this is a bi-functional key, just press for making a measurement, or hold the key
for 3 seconds to start a pre-programmed countdown prior to measurement.
• CAL CHECK: this bi-functional key allows to perform validation of the instrument just pressing
the CAL CHECK key, or hold the key for 3 seconds to enter the calibration mode.
OPERATING MODES
• Measurement mode: default operation mode, enables both validation and measurement.
• Calibration mode: may be entered by keeping CAL CHECK pressed for three seconds (the “CAL”
icon appears), it enables calibration of the instrument.
1) Liquid Crystal Display (LCD)
2) Cuvet Holder
3) Cuvet alignment indicator
4) ON/OFF key
5) ZERO/SET key
6) READ/TIMER key
7) CAL CHECK key
FUNCTIONAL DESCRIPTION
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• Select the parameter code for free chlorine “734f”
or total chlorine “734t” by holding ZERO/SET
(see page 14).
• Place the CAL CHECK™ Standard Cuvet A into
the holder and ensure that the notch on the cap is
positioned securely into the groove.
• Press ZERO and “SIP” will blink on the display.
• After a few seconds the display will show “-0.0-”.
The meter is now zeroed and ready for validation.
• Remove the cuvet.
• Place the CAL CHECK™ Standard HI 95734-11
Cuvet B into the holder and ensure that the notch
on the cap is positioned securely into the groove.
• Press CAL CHECK and “SIP” will blink during
measurement.
• Wait for a few seconds and the display will show the validation standard value.
The reading should be within specifications as  reported on the CAL CHECK™ Standard Certificate.
If the value is found out of specifications, please check that the cuvets are free of fingerprints, oil or
dirt and repeat validation. If results are still found out of specifications then recalibrate the
instrument.
Use the validation procedure to ensure that the instrument is properly calibrated.
Warning: do not validate or calibrate the instrument with standard solutions other than the Hanna
CAL CHECK™
 
Standards, otherwise erroneous results will be obtained.
For accurate Validation and Calibration results, please perform test at room temperature: 18 to 25°C
(64.5 to 77.0°F).
Temperature correction for Validation: corrected value = read value 
× [1 + 0.002 × (20 − T(°C))]
corrected value = read value 
× [1 + 0.001 × (68 − T(°F))]
VALIDATION PROCEDURE