Hanna Instruments HI 96822 User Manual

Instruction Manual

HI 96822

Seawater Refractometer

www.hannainst.com

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Dear Customer,
Thank you for choosing a Hanna product. This manual will provide you with the necessary

information for the correct use of this instrument. Please read it carefully before using the meter. If
you need additional technical information, do not hesitate to e-mail us at [e-mail].

This instrument is in compliance with

directives.

TABLE OF CONTENTS

PRELIMINARY EXAMINATION ............................................................................................. 2

GENERAL DESCRIPTION .....................................................................................................3

SPECIFICATIONS .................................................................................................................. 3

PRINCIPLE OF OPERATION ................................................................................................4

FUNCTIONAL DESCRIPTION................................................................................................ 5

DISPLAY ELEMENTS............................................................................................................ 6

MEASUREMENT GUIDELINES .............................................................................................. 6

CALIBRATION PROCEDURE ................................................................................................ 7

MEASUREMENT PROCEDURE ............................................................................................. 8

TO CHANGE MEASUREMENT UNIT .....................................................................................9

TO CHANGE TEMPERATURE UNIT...................................................................................... 9

MAKING A STANDARD SOLUTION...................................................................................... 9

BATTERY REPLACEMENT .................................................................................................10

WARRANTY ........................................................................................................................ 10

ERROR MESSAGES ............................................................................................................11

PRELIMINARY EXAMINATION

Remove the instrument from the packing materials and examine carefully to ensure no
damage has occurred during shipping. If any damage has occurred, notify your Dealer
or closest Hanna Customer Service Center.

Each instrument is supplied with:

• 9 V battery

• Instruction manual

Note:Save all packing material until you are sure that the instrument functions

correctly. A defective instrument must be returned in its original packing.

All rights are reserved. Reproduction in whole or in part is prohibited without the written consent of the
copyright owner, Hanna Instruments Inc., Woonsocket, Rhode Island, 02895, USA.

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GENERAL DESCRIPTION

The HI 96822 Digital Refractometer is a rugged portable, water resistant device that utilizes the
measurement of refractive index to determine the salinity of natural and artificial seawater, ocean
water or brackish intermediates.
The HI 96822 device benefits from Hanna’s years of experience as a manufacturer of analytical
instruments. The digital refractometer eliminates the uncertainty associated with mechanical refrac­tometers and is easily potable for ship, shore or home use.
The HI 96822 refractometer is an optical device that is simple and quick to use. After a simple user
calibration with distilled or deionized water, a seawater sample is in introduced to the sample well.
Within seconds, the refractive index and temperature are measured and converted into one of 3
popular measurement units; Practical Salinity Units (PSU), Salinity in parts per thousand (PPT), or
Specific Gravity (S.G. (20/20)). All conversion algorithms are based upon respected scientific
publications using the physical properties of seawater (not sodium chloride). The temperature (in °C
or °F) is also displayed on the large dual level display along with helpful message codes.
Key features include:

• IP65 waterproof protection

• Automatic Temperature Compensation (ATC)

• Battery operation with Low Power indicator (BEPS)

• Automatically turns off after 3 minutes of non-use

SPECIFICATIONS

USPTPP)02/02(.G.S)F°(C°

:egnaR 05ot0051ot0411.1ot000.1)F°671ot23(C°08ot0

:noituloseR 11 100.0)F°1.0(C°1.0

:ycaruccA 2

±2±200.0±)F°5.0±(C°3.0±

Temperature Compensation: Automatic between 0 and 40 °C (32 - 104 °F)
Measurement Time: Approximately 1.5 seconds
Minimum Sample Volume: 100 μL (cover prism totally)
Light Source: Yellow LED
Sample Cell: Stainless Steel ring and flint glass prism
Case Material: ABS
Enclosure Rating: IP 65
Battery Type / Life: 1 X 9V / 5000 readings
Auto-Off: After 3 minutes of non-use
Dimensions: 19.2(W) x 10.2(D) x 6.7(H) cm
Mass: 420 g

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PRINCIPLE OF OPERATION

Salinity determinations are made by measuring the refractive index of seawater. Refractive Index is
an optical characteristic of a substance and the number of dissolved particles in it. Refractive Index
is defined as the ratio of the speed of light in empty space to the speed of light in the substance. A
result of this property is that light will “bend”, or change direction, when it travels through a
substance of different refractive index. This is called refraction.
When passing from a material with a higher to lower refractive index, there is a critical angle at
which an incoming beam of light can no longer refract, but will instead be reflected off the interface.

The critical angle can be used to easily calculate the refractive index according to the equation:

sin (θ

) = n2 / n

critical

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Where n2 is the refractive index of the lower-density medium; n1 is the refractive index of the
higher-density medium.

In the HI 96822 refractometer, light from an LED passes through a prism in contact with the sample.
An image sensor determines the critical angle at which the light is no longer refracted through the
sample.
Specialized algorithms then apply temperature compensation to the measurement and convert the
refractive index to: PSU, PPT or S.G. (20/20).
PSU is defined as a definitive salinity-conductivity ratio relationship. It is based upon the work of
the UNESCO, ICES, SCOR and IAPSO. This information is published in The Joint Panal of Oceanographic
Tables and Standards. PPT (10-3) is an older used salinity scale where salinity is defined by “the
salt content is the weight of the inorganic salts contained in 1 kg of seawater if all bromide and
iodide are replaced by an equivalent amount of oxides” (Knudsen, 1901).

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