User Guide

7
A microprocessor controlled special tungsten lamp emits radiation which is first optically conditioned
and beamed to the sample contained in the cuvet. The optical path is fixed by the diameter of the
cuvet. Then the light is spectrally filtered to a narrow spectral bandwidth, to obtain a light beam of
intensity I
o
or I.
The photoelectric cell collects the radiation I that is not absorbed by the sample and converts it
into an electric current, producing a potential in the mV range.
The microprocessor uses this potential to convert the incoming value into the desired measuring
unit and to display it on the LCD.
The measurement process is carried out in two phases: first the meter is zeroed and then the actual
measurement is performed.
The cuvet has a very important role because it is an optical element and thus requires particular
attention. It is important that both the measurement and the calibration (zeroing) cuvets are
optically identical to provide the same measurement conditions. Whenever possible use the same
cuvet for both. It is necessary that the surface of the cuvet is clean and not scratched. This to avoid
measurement interference due to unwanted reflection and absorption of light. It is recommended
not to touch the cuvet walls with hands.
Furthermore, in order to maintain the same conditions during the zeroing and the measuring
phases, it is necessary to close the cuvet to prevent any contamination.
degree Celsius
degree Fahrenheit
grams per liter. g/L is equivalent to ppt (part per thousand)
milliliter
microliter
Liquid Crystal Display
°C:
°F:
g/L:
mL:
µL:
LCD:
ABBREVIATIONS
14
• Insert the vials into the reactor and heat them for 7
minutes at 105°C.
Note: to obtain most accurate results, it is
recommended to use the pre-programmed timer of
the instrument, and remove the vials from the reactor
after exactly 7 minutes.
Turn the meter on by pressing ON/OFF and then
press TIMER to activate a 7 minutes countdown.
• At the end of the digestion period switch off the reactor,
place the vials carefully in the test tube rack and wait
for 10 minutes.
Warning: as the vials are still hot, be careful in
handling them.
Note: If the sample vial appears brown/orange
without blue hue, dilute the wine sample and repeat
the procedure.
• Invert the vials two times to mix. Then wait for 30
minutes to allow the vials cool to room temperature.
Note: This operation is necessary to recover the
condensed water after heating.
• Turn the instrument ON by pressing ON/OFF. When the
LCD displays “---”, it is ready.
• Place the Blank Vial into the instrument.
• Press ZERO and “----” will blink on the display.
Blank