Hanna Instruments HI 96715 User Manual

0 (0)

Instruction Manual

HI 96715C

Ammonia Medium Range ISM

w w w . h a n n a i n s t . c o m

1

Hanna Instruments HI 96715 User Manual

Dear Customer,

Thank you for choosing a Hanna product. This manual will provide you with the necessary information for the correct use of the 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.

 

TABLE OF CONTENTS

 

PRELIMINARY EXAMINATION ................................................................................................

3

GENERAL DESCRIPTION .......................................................................................................

4

ABBREVIATIONS ..................................................................................................................

4

SPECIFICATIONS ...................................................................................................................

5

PRECISION AND ACCURACY ..................................................................................................

5

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

6

FUNCTIONAL DESCRIPTION ..................................................................................................

7

ERRORS AND WARNINGS ....................................................................................................

9

GENERAL TIPS FOR AN ACCURATE MEASUREMENT .............................................................

11

STARTUP

...........................................................................................................................

13

MEASUREMENT .............................................................................................PROCEDURE

13

VALIDATION ...................................................................................................PROCEDURE

15

CALIBRATION .................................................................................................PROCEDURE

17

GLP ...................................................................................................................................

 

20

BATTERY ....................................................................................................

MANAGEMENT

21

BATTERY ....................................................................................................

REPLACEMENT

22

ACCESSORIES .....................................................................................................................

22

WARRANTY ........................................................................................................................

23

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.

PRELIMINARY EXAMINATION

Please examine this product carefully. Make sure that the instrument is not damaged. If any damage occurred during shipment, please notify your Dealer.

Each HI 96715 Ion Selective Meter is supplied complete with:

Two Sample Cuvettes and Caps

Two CAL CHECKTM standard cuvettes HI 96715KIT

9V Battery

Tissue for wiping cuvettes

Instrument quality certificate

Instruction Manual

Rigid carrying case

Note: Save all packing material until you are sure that the instrument works correctly. Any defective item must be returned in its original packing.

2

3

GENERAL DESCRIPTION

The HI 96715 is an auto diagnostic portable microprocessor meter that benefits from Hanna’s years of experience as a manufacturer of analytical instruments. It has the advanced optical system based on a special tungsten lamp and a narrow band interference filter that allows most accurate and repeatable readings. All instruments are factory calibrated and the electronic and optical design minimizes the need of frequent calibration.

With the powerful CAL CHECKTM validation function, you are able to validate good performance of your instrument at any time. The validation procedure is extremely user friendly. Just use the exclusive HANNA ready-made, NIST traceable standards to verify the performance of the instrument and recalibrate if necessary.

The instrument is splash waterproof and the LED and filter units are protected from dust or dirt by a transparent cup. This makes the instruments fulfill field applications. Display messages aid the user in routine operation. The meter has an auto-shut off feature that will turn off the instrument after 10 minutes of non use in measurement mode or after 1 hour if left in calibration mode.

The meter uses an exclusive positive-locking system to ensure that the cuvette is in the same position every time it is placed into the measurement cell. It is designed to fit a cuvette with a larger neck making it easier to add both sample and reagents. The cuvette is made from special optical glass to obtain best results.

The HI 96715 meter measures the ammonia nitrogen (NH3-N) content in water samples in the 0.00 to 9.99 mg/L (ppm) range. The method is an adaptation from ASTM Manual of Water and Environmental Technology, D1426-93, Nessler Method.

The reagents are liquid form and are supplied in bottles. The amount of reagent is precisely dosed to ensure the maximum repeatability.

ABBREVIATIONS

°C: degree Celsius °F: degree Fahrenheit

mg/L: milligrams per liter. mg/L is equivalent to ppm (parts per million) mL: milliliter

LED: Light Emitting Diode

LCD: Liquid Crystal Display

ASTM: American Society for Testing and Materilas 4

 

SPECIFICATIONS

Range

0.00 to 9.99 mg/L (as NH3-N)

Resolution

0.01 mg/L for measurement

 

0.1 mg/L for calibration and validation

Accuracy

±0.05 mg/L ±5% of reading @ 25°C

Typical EMC Deviation

±0.01 mg/L

Light Source

Light Emitting Diode

Light Detector

Silicon Photocell with narrow band interference filter @ 466 nm

Method

Adaptation of the ASTM Manual of Water and Environmental Technology,

 

D1426-93, Nessler Method. The reaction between ammonia and the

 

reagents causes a yellow tint in the sample.

Environment

0 to 50°C (32 to 122°F); max 95% RH non-condensing

Battery Type

1 x 9 volt

Auto-Shut off

After 10’ of non-use in measurement mode;

 

after 1 hour of non-use in calibration mode;

 

with last reading reminder.

Dimensions

192 x 104 x 69 mm (7.6 x 4.1 x 2.7”)

Weight

360 g (12.7 oz.).

REQUIRED REAGENTS

 

 

Code

Description

Quantity/test

HI

93715A-0

First Reagent

4 drops (6 drops in seawater)

HI

93715B-0

Second Reagent

4 drops (10 drops in seawater)

PRECISION AND ACCURACY

Precision is how closely repeated measurements agree with each other. Precision is usually expressed as standard deviation (SD).

Accuracy is defined as the nearness of a test result to the true value.

Although good precision suggests good accuracy, precise results can be inaccurate. The figure explains these definitions.

In a laboratory using a standard solution of 6.00 mg/L ammonia nitrogen (NH3-N) and a representative lot of reagents, an operator obtained with a single instrument a standard deviation of 0.12 mg/L.

5

PRINCIPLE OF OPERATION

Absorption of Light is a typical phenomenon of interaction between electromagnetic radiation and matter. When a light beam crosses a substance, some of the radiation may be absorbed by atoms, molecules or crystal lattices.

If pure absorption occurs, the fraction of light absorbed depends both on the optical path length through the matter and on the physical-chemical characteristics of the substance according to the Lambert-Beer Law:

 

 

-log I/Io = ελ c d

 

 

or

 

 

A = ελ c d

Where:

 

 

-log I/Io =

Absorbance (A)

Io

=

intensity of incident light beam

I

=

intensity of light beam after absorption

ελ

=

molar extinction coefficient at wavelength λ

c

=

molar concentration of the substance

d

=

optical path through the substance

Therefore, the concentration "c" can be calculated from the absorbance of the substance as the other factors are known.

Photometric chemical analysis is based on the possibility to develop an absorbing compound from a specific chemical reaction between sample and reagents. Given that the absorption of a compound strictly depends on the wavelength of the incident light beam, a narrow spectral bandwidth should be selected as well as a proper central wavelength to optimize measurements. The optical system of Hanna's HI 96715 colorimeter is based on a Light Emitting Diode (LED) combined with a narrow-band interference filter to guarantee both high performance and reliable results.

HI 96715 block diagram (optical layout)

A microprocessor controlled LED emits radiation which is first optically conditioned and beamed to the sample contained in the cuvette. The optical path is fixed by the diameter of the cuvette. Then the light is spectrally filtered to a narrow spectral bandwidth, to obtain a light beam of intensity Io 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 cuvette 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) cuvettes, are optically identical to provide the same measurement conditions. Whenever possible use the same cuvette for both. It is necessary that the surface of the cuvette 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 cuvette walls with hands.

Furthermore, in order to maintain the same conditions during the zeroing and the measuring phases, it is necessary to close the cuvette to prevent any contamination.

FUNCTIONAL DESCRIPTION

INSTRUMENT DESCRIPTION

1)

GLP/

key

2)

CAL CHECK key

3)

ZERO/CFM key

4)

READ/

/TIMER key

5)

ON/OFF key

6)

Liquid

Crystal Display (LCD)

7)

Cuvette

alignment indicator

8)

Cuvette holder

6

7

Loading...
+ 9 hidden pages