Instruction Manual HI 96821 Refractometer for Sodium Chloride Measurements w w w. h a n n a i n s t .
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 tech@hannainst.com. This instrument is in compliance with directives. TABLE OF CONTENTS PRELIMINARY EXAMINATION ............................................................................................. 2 GENERAL DESCRIPTION .
GENERAL DESCRIPTION The HI 96821 Digital Refractometer is a rugged portable, water resistant device that benefits from Hanna’s years of experience as a manufacturer of analytical instruments. The HI 96821 is an optical instrument that employs the measurement of the refractive index to determine sodium chloride concentration in aqueous solutions used in food preparation. It is not intended for sea water salinity measurements.
PRINCIPLE OF OPERATION Aqueous NaCl determinations are made by measuring the refractive index of a solution. 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.
FUNCTIONAL DESCRIPTION TOP VIEW 1. 2. 3. 4. 5. 6. 7. 8. Liquid Crystal Display (LCD) READ Key (User Measurement) ZERO Key (User Calibration) RANGE Key (User Measurement Unit) ON/OFF Stainless Steel Sample Well and Prism Secondary Display Primary Display BOTTOM 9. Battery Cover 10.
DISPLAY ELEMENTS 1. 2. 3. 4. 5. 6 7. 8. 9.
CALIBRATION PROCEDURE Calibration should be performed daily, before measurements are made, when the battery has been replaced, or between a long series of measurements. 1. Press the ON/OFF key, then release. Two instrument test screens will be displayed briefly; all LCD segments followed by the percentage of remaining battery life. It will briefly display an indication of the measurement units set. When the LCD displays dashes, the instrument is ready. 2.
MEASUREMENT PROCEDURE Verify the instrument has been calibrated before taking measurements. 1. Wipe off prism surface located at the bottom of the sample well. Make sure the prism and sample well are completely dry. 2. Using a plastic pipette, drip sample onto the prism surface. Fill the well completely. Note: If the temperature of the sample differs significantly from the temperature of the instrument, wait approximately 1 minute to allow thermal equilibration. 3. Press the READ key.
TO CHANGE MEASUREMENT UNIT Press the RANGE key to select measurement units. The instrument toggles between the four measurement scales each time the key is pressed and the primary display indicates “G-G” for g/100 g, “G-L” for g/100 mL, “S.G.” for Specific Gravity and “bAU” for °Baumé. When the instrument displays the screen with 4 dashes, the instrument is ready for measurement.
MAKING A STANDARD SODIUM CHLORIDE SOLUTION To make a Standard NaCl Solution (g/100 g), follow the procedure below: • Place container (such as a glass vial or dropper bottle that has a cover) on an analytical balance. • Tare the balance. • To make an X NaCl solution weigh out X grams of high purity dried Sodium Chloride (CAS #: 7647-14-5: MW 58.44) directly into the container. • Add distilled or deionized water to the container so the total weight of the solution is 100 g.
ERROR MESSAGES Error Code LCD Descript ion “Err“ G e n e ra l f a i l u re . C y c l e p owe r t o instrument. If error p ersists, conta ct Ha nna . “LO“ Prima ry d isp la y Sa mp le is rea d ing lower tha n the 0 sta n d a rd u sed for m eter ca lib ra tion. “HI “ Prima ry d isp la y Sa m p l e exceed s m a xi m u m mea surement ra ng e. “LO“ Prima ry d isp la y “CAL“ seg ment ON W ron g sol u ti on u sed to zero i n stru m e n t. U se d e i on i ze d or d istilled wa ter. Press ZERO.
Hanna Instruments Inc. Highland Industrial Park 584 Park East Drive Woonsocket RI 028985 USA Local Sales and Customer Service office Hanna Instruments United States Inc. Highland Industrial Park 584 Park East Drive Woonsocket RI 028985 USA Tel. (800) 426 6287 Fax (401) 765 7575 www.hannainst.com/usa Technical Support for customers Telephone (800) 426 6287 Fax (401) 765 7575 E-mail tech@hannainst.
