Hanna Instruments HI 93124 User Manual

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FUNCTIONAL DESCRIPTION

1) RS232 connector
2) Measurement cell
3) Liquid Crystal Display
4) ON/OFF key, to switch the meter ON and OFF; CLR key, to clear log memory

(with ALT)

5) GLP key, to display last calibration date and time; CAL key, to enter calibration

mode (with ALT)

6) ALT key, to activate alternate functions
7) READ key, to perform measurements; DATE key, to display (toggle) current date

and time (with ALT)

8) STO key, to store sample after reading; VIEW key, to view log memory (with ALT)

GENERAL DESCRIPTION

Beer clarity is a parameter constantly controlled in brewery, and to assure a consistent
product quality, the brewmaster needs more than visual inspection.
Several substances can cause haze in beer, but the most frequently encountered
problem is due to a cross-linking of polyphenol and protein. These materials probably
exist in equilibrium in beer and manifest themselves as a haze when the polyphenol
polymerizes.
A range of stabilization treatments is available for avoiding haze problems, and
the product has to be controlled on several steps during brewing process, in particular
after filtration and before the beer enters the single tanks.

HI 93124 is a portable Haze meter, especially designed for application in brewery.

The instrument is also provided with a log-on-demand feature, which allows the
user to store up to 199 samples into the internal memory.

HI 93124 has been designed to perform turbidity measurements according to the
EBC (European Brewery Convention) Standard.
The instrument functions by passing a beam of infrared light through a cuvette
containing the sample being measured. The light source is a High Emission Infrared
LED with a wavelength peaking at 890 nm, ensuring that the interference caused
by colored samples is minimum.
A sensor, positioned at 90° with respect to the direction of light, detects the amount
of light scattered by the undissolved particles present in the sample.

The microprocessor converts such readings into EBC values.

PRINCIPLE OF OPERATION