Hanna Instruments HI 83213 User Manual

Instruction Manual
HI 83213
Multiparameter Bench
Photometer
for Municipal Wastewater
www.hannainst.com
1
Dear Customer, Thank you for choosing a Hanna product. Please read this instruction manual carefully before using the
instrument. This manual will provide you with the necessary information for the correct use of the instrument. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst.com.
TABLE OF CONTENTS
PRELIMINARY EXAMINATION ............................................. 3
ABBREVIATIONS ............................................................... 3
GENERAL DESCRIPTION ..................................................... 3
SPECIFICATIONS .............................................................. 4
PRECISION AND ACCURACY ............................................... 4
PRINCIPLE OF OPERATION ................................................ 4
FUNCTIONAL DESCRIPTION ............................................... 6
TIPS FOR AN ACCURATE MEASUREMENT ........................... 8
HEALTH & SAFETY ..........................................................11
METHOD REFERENCE TABLE ............................................. 11
OPERATIONAL GUIDE ....................................................... 12
SETUP ........................................................................... 14
HELP MODE ................................................................... 16
ALUMINUM ....................................................................17
AMMONIA MR ................................................................ 19
AMMONIA LR .................................................................21
BROMINE ......................................................................23
FREE CHLORINE ............................................................. 25
TOTAL CHLORINE ............................................................28
CHROMIUM VI HR ..........................................................31
CHROMIUM VI LR ...........................................................33
COLOR OF WATER ........................................................... 35
COPPER HR ....................................................................37
COPPER LR .................................................................... 39
IODINE .......................................................................... 41
NICKEL HR ..................................................................... 43
NICKEL LR ...................................................................... 45
NITRATE .........................................................................48
NITRITE HR .................................................................... 50
NITRITE LR .....................................................................52
DISSOLVED OXYGEN ........................................................54
pH ................................................................................56
PHOSPHATE HR ..............................................................58
PHOSPHATE LR ...............................................................60
PHOSPHORUS ...............................................................62
SILVER ..........................................................................64
ZINC ..............................................................................67
ERRORS AND WARNINGS ................................................. 69
DATA MANAGEMENT ........................................................ 70
STANDARD METHODS ......................................................71
ACCESSORIES ................................................................72
WARRANTY .................................................................... 74
HANNA LITERATURE ........................................................ 75
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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PRELIMINARY EXAMINATION
Please examine this product carefully. Make sure that the instrument is not damaged. If any damage occurred during shipment, please notify your local Hanna Office.
Each Meter is supplied complete with:
• Four Sample Cuvettes and Caps
• Cloth for wiping cuvettes (1 pcs)
• 60 mL glass bottle for dissolved oxygen analysis (1 pcs)
• Scissors
• AC/DC Power Adapter
• Instruction Manual
Note: Save all packing material until you are sure that the instrument works correctly. Any defective item
must be returned in its original packing with the supplied accessories.
ABBREVIATIONS
EPA: US Environmental Protection Agency
°C: degree Celsius °F: degree Fahrenheit
μg/L: micrograms per liter (ppb)
mg/L: milligrams per liter (ppm)
g/L: grams per liter (ppt)
mL: milliliter
HR: high range
LR: low range
MR: medium range
PAN: 1-(2-pyridylazo)-2-naphtol
TPTZ: 2,4,6-tri-(2-pyridyl)-1,3,5-triazine
GENERAL DESCRIPTION
HI 83213 is a multiparameter bench photometer dedicated for Municipal Wastewater analysis. It measures 24 different methods using specific liquid or powder reagents. The amount of reagent is precisely dosed to ensure maximum reproducibility.
HI 83213 bench photometer can be connected to a PC via an USB cable. The optional HI 92000 Windows® Compatible Software helps users manage all their results.
HI 83213 has a powerful interactive user support that assists the user during the analysis process. Each step in the measurement process is help supported. A tutorial mode is available in the Setup Menu.
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SPECIFICATIONS
Light Life Life of the instrument Light Detector Silicon Photocell Environment 0 to 50°C (32 to 122°F);
max 90% RH non-condensing
Power Supply external 12 Vdc power adapter
built-in rechargeable battery
Dimensions 235 x 200 x 110 mm (9.2 x 7.87 x 4.33") Weight 0.9 Kg
For specifications related to each method (e.g. range, precision, etc.) refer to the related measurement section.
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.
For each method, the precision is expressed in the related measurement section.
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 substance according to the Lambert-Beer Law:
-log I/Io = ε A = ε
c d
λ
or
c d
λ
4
Where:
-log I/I
=Absorbance (A)
o
Io=intensity of incident light beam I =intensity of light beam after absorption
ε
=molar extinction coefficient at wavelength λ
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 HI 83213 is based on special subminiature tungsten lamps and narrow-band interference filters to guarantee both high performance and reliable results.
Five measuring channels allow a wide range of tests.
Instrument block diagram (optical layout)
A microprocessor controlled special tungsten lamp emits radiation which is first optically conditioned and beamed trough 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) cuvette are optically identical to provide the same measurement conditions. Most methods use the same cuvette for both, so it is important that measurements are taken at the same optical point. The instrument and the cuvette cap have special marks that must be aligned in order to obtain better reproducibility.
The surface of the cuvette must be clean and not scratched. This is 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 measurement phases, it is necessary to cap the cuvette to prevent any contamination.
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FUNCTIONAL DESCRIPTION
INSTRUMENT DESCRIPTION
1) Open Cuvette Lid
2) Indexing mark
3) Cuvette point
4) Liquid Crystal Display (LCD)
5) Splash proof keypad
6) ON/OFF power switch
7) Power input connector
8) USB connector
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KEYPAD DESCRIPTION
The keypad contains 8 direct keys and 3 functional keys with the following functions:
Press to perform the function displayed above it on the LCD.
ESC
Press to exit the current screen.
Press to access the select method menu.
Press to move up in a menu or a help screen, to increment a set value, to access second level
functions.
Press to move down in a menu or a help screen, to decrement a set value, to access second
level functions.
Press to log the current reading.
RCL
Press to recall the log.
HELP
SETUP
Press to display the help screen.
Press to access the setup screen.
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TIPS FOR AN ACCURATE MEASUREMENT
The instructions listed below should be carefully followed during testing to ensure most accurate results.
• Color or suspended matter in large amounts may cause interference, and should be removed by treatment with active carbon and filtration.
• Ensure the cuvette is filled correctly: the liquid in the cuvette forms a convexity on the top; the bottom of this convexity must be at the same level as the 10 mL mark.
COLLECTING AND MEASURING SAMPLES
• In order to measure exactly 0.5 mL of reagent with the 1 mL syringe: (a) push the plunger completely into the syringe and insert the tip into the solution. (b) pull the plunger up until the lower edge of the seal is exactly on the 0.0 mL mark. (c) take out the syringe and clean the outside of the syringe tip. Be sure that no drops are hanging
on the tip of the syringe, if so eliminate them. Then, keeping the syringe in vertical position above the cuvette, push the plunger down into the syringe until the lower edge of the seal is exactly on the 0.5 mL mark. Now the exact amount of 0.5 mL has been added to the cuvette, even if the tip still contains some solution.
USING LIQUID AND POWDER REAGENTS
• Proper use of the dropper: (a) for reproducible results, tap the dropper on the table for several times and wipe the outside of the
dropper tip with a cloth.
(b) always keep the dropper bottle in a vertical position while dosing the reagent.
(a) (b)
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• Proper use of the powder reagent packet: (a) use scissors to open the powder packet; (b) push the edges of the packet to form a spout; (c) pour out the content of the packet.
USING CUVETTES
• Proper mixing is very important for reproducibility of the measurements. The right way of mixing a cuvette is specified for each method in the related chapter.
(a) invert the cuvette a couple of times or for a specified time: hold the cuvette in the vertical position. Turn
the cuvette upside-down and wait for all of the solution to flow to the cap end, then return the cuvette to the upright vertical position and wait for all of the solution to flow to the cuvette bottom. This is one inversion. The correct speed for this mixing technique is 10-15 complete inversions in 30 seconds.
This mixing technique is indicated with “invert to mix” and the following icon:
(b) shaking the cuvette, moving the cuvette up and down. The movement may be gentle or vigorous.
This mixing method is indicated with “shake gently” or “shake vigorously”, and one of the following icons:
shake gently shake vigorously
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• Pay attention to push the cuvette completely down in the holder and to align the white point on the cap to the indexing mark on the meter.
• In order to avoid reagent leaking and to obtain more accurate measurements, close the cuvette first with the supplied HDPE plastic
stopper and then the black cap.
• Each time the cuvette is used, the cap must be tightened to the same degree.
• Whenever the cuvette is placed into the measurement cell, it must be dry outside, and free of fingerprints, oil or dirt. Wipe it thoroughly with HI 731318 or a lint-free cloth prior to insertion.
• Shaking the cuvette can generate bubbles in the sample, causing higher readings. To obtain accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette.
• Do not let the reacted sample stand too long after reagent is added. For best accuracy, respect the timings described in each specific method.
• It is possible to take multiple readings in a row, but it is recommended to take a new zero reading for each sample and to use the same cuvette for zeroing and measurement when possible (for most precise results follow the measurement procedures carefully).
• Discard the sample immediately after the reading is taken, or the glass might become permanently stained.
• All the reaction times reported in this manual are at 25 °C (77 °F). In general, the reaction time should be increased for temperatures lower than 20 °C (68 °F), and decreased for temperatures higher than 25 °C (77 °F).
INTERFERENCES
• In the method measurement section the most common interferences that may be present in an average wastewater matrix have been reported. It may be that for a particular treatment process other compounds do interfere with the method of analysis.
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HEALTH & SAFETY
• The chemicals contained in the reagent kits may be hazardous if improperly handled.
• Read the Material Safety Data Sheet (MSDS) before performing tests.
• Safety equipment: Wear suitable eye protection and clothing when required, and follow instructions carefully.
• Reagent spills: If a reagent spill occurs, wipe up immediately and rinse with plenty of water. If reagent contacts skin, rinse the affected area thoroughly with water. Avoid breathing released vapors.
• Waste disposal: for proper disposal of reagent kits and reacted samples, refer to the Material Safety Data Sheet (MSDS).
METHOD REFERENCE TABLE
Method Method Page
description
1 Aluminum 17
2 Ammonia MR 19
3 Ammonia LR 21
4 Bromine 23
5 Free Chlorine 25
6 Total Chlorine 28
7 Chromium VI HR 31
8 Chromium VI LR 33
9 Color of Water 35
10 Copper HR 37
11 Copper LR 39
12 Iodine 41
Method Method Page
description
13 Nickel HR 43
14 Nickel LR 45
15 Nitrate 48
16 Nitrite HR 50
17 Nitrite LR 52
18 Dissolved Oxygen 54
19 pH 56
20 Phosphate HR 58
21 Phosphate LR 60
22 Phosphorus 62
23 Silver 64
24 Zinc 67
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OPERATIONAL GUIDE
POWER CONNECTION AND BATTERY MANAGEMENT
The meter can be powered from an AC/DC adapter (included) or from the built-in rechargeable battery. Note: Always turn the meter off before unplugging it to ensure no data is lost. When the meter switches ON, it verifies if the power supply adapter is connected. The battery icon on the
LCD will indicate the battery status:
- battery is charging from external adapter - battery fully charged (meter connected to AC/DC adapter)
- battery capacity (no external adapter) - battery Low (no external adapter)
- battery Dead (no external adapter)
METHOD SELECTION
Turn the instrument ON via the ON/OFF power switch.
The meter will perform an autodiagnostic test. During this test, the Hanna Instrument logo will appear
on the LCD. After 5 seconds, if the test was successful, the last method used will appear on the display.
In order to select the desired method press the METHOD key and a screen with the available methods
will appear.
Press keys to highlight the desired method. Press Select.
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After the desired method is selected, follow the measurement described in the related section.
Before performing a test you should read all the instructions carefully.
DATA MANAGEMENT
The instrument features a data log function to help you keep track of all your analysis. The data log can hold 200 individual measurements. Storing, viewing and deleting the data is possible using the LOG and
RCL keys
Storing data
stored with date and time stamps.
..
.
..
: You can store only a valid measurement. Press LOG
and the last valid measurement will be
Viewing and deleting
the last saved measurement. Additionally, you can delete the data records all at once.
: You can view and delete the data log by pressing the RCL key. You can only delete
CHEMICAL FORM
Chemical form conversion factors are pre-programmed into the instrument and are method specific. In order to view the displayed result in the desired chemical form press or to access the second level functions and then press the Chem Frm functional key to toggle between the available chemical forms for the selected method.
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SETUPSETUP
SETUP
SETUPSETUP
In the Setup mode the instrument’s parameters can be changed. Some parameters affect the measuring sequence and others are general parameters that change the behavior or appearance of the instrument.
Press SETUP to enter the setup mode. Press ESC or SETUP to return to the main screen. A list of setup parameters will be displayed with currently configured settings. Press HELP for additional information.
Press the   value as follows:
keys to select a parameter and change the
Backlight
Values: 0 to 8.
Press the Modify key to access the backlight value. Use the W X functional keys or the   keys to increase or decrease the value. Press the Accept key to confirm or ESC to return to the setup
menu without saving the new value.
Contrast
Values: 0 to 20.
This option is used to set the display’s contrast. Press the Modify key to change the display’s contrast. Use the W X functional keys or the   keys to increase or decrease the value. Press the Accept key to confirm the value or ESC to return to the
setup menu without saving the new value.
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Date / Time
This option is used to set the instrument’s date and time. Press the Modify key to change the date/time. Press the W X functional keys to highlight the value to be modified (year, month, day, hour, minute or second). Use the keys to change the value. Press the Accept key to confirm or ESC to return to the setup
without saving the new date or time.
Time format
Option: AM/PM or 24 hour.
Press the functional key to select the desired time format.
Date format
Press the Modify key to change the Date Format. Use the   keys to select the desired format. Press the Accept key to confirm or ESC to return to the setup
menu without saving the new format.
Language
Press the corresponding key to change the language. If the new language cannot be loaded, the previously selected language will be reloaded.
Tutorial
Option: Enable or Disable.
If enabled this option will provide the user short guide related to the current screen. Press the functional key to enable/disable the tutorial mode.
Beeper
Option: Enable or Disable.
When enabled, a short beep is heard every time a key is pressed. A long beep alert sounds when the pressed key is not active or an error condition is detected.
Press the functional key to enable/disable the beeper.
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Instrument ID
Option: 0 to 9999.
This option is used to set the instrument’s ID (identification number). The instrument ID is used while exchanging data with a PC. Press the Modify key to access the instrument ID screen. Press the   keys in order to set the desired value. Press the Accept key to confirm the value or ESC to return to the setup menu without saving the new value.
Meter information
Press the Select key to view the instrument model, firmware version, language version and instrument serial number.
Press ESC to return to the Setup mode.
HELP MODEHELP MODE
HELP MODE
HELP MODEHELP MODE
HELP MODE
HI 83213 offers an interactive contextual help mode that assists the user at any time.
To access the help screens press HELP. The instrument will display additional information related to the current screen. To read all the available information, scroll the text using the   keys. Press the Support key to access a screen with Hanna service centers and their contact details. Press the Accessories key to access a list of instrument reagents and accessories. To exit support or accessories screens press ESC and the instrument will return to the previous help screen. To exit help mode press the HELP or ESC key again and the meter will return to the previously selected screen.
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ALUMINUM
SPECIFICATIONS
Range 0.00 to 1.00 mg/L Resolution 0.01 mg/L Accuracy ±0.02 mg/L ±4% of reading at 25 °C Typical EMC ±0.01 mg/L
Deviation Light Source Tungsten lamp with narrow band interference filter @ 525 nm Method Adaptation of the aluminon method. The reaction between aluminum and reagents
causes a reddish tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93712A-0 Ascorbic acid 1 packet HI 93712B-0 Aluminon reagent 1 packet HI 93712C-0 Bleaching powder 1 packet
REAGENT SETS
HI 93712-01 Reagents for 100 tests HI 93712-03 Reagents for 300 tests
For other accessories see page 72.
MEASUREMENT PROCEDURE
• Select the the
Aluminum
Method Selection
method using the procedure described in section (see page 12).
• Fill a graduated beaker with 50 mL of sample.
• Add the content of one packet of HI 93712A-0 Ascorbic acid and mix until completely dissolved.
• Add the content of one packet of HI 93712B-0 Aluminon reagent and mix until completely dissolved. This is the sample.
• Fill two cuvettes with 10 mL of sample each (up to the mark).
17
10 mL
# 1
10 mL
# 2
Aluminum
• Add the content of one packet of HI 93712C-0 Bleaching powder to one of the two cuvettes. Replace the cap and shake vigorously until completely dissolved. This is the blank.
• Place the blank into the holder and close the lid.
# 1
• Press Timer and the display will show the countdown prior to
# 1
zeroing the blank. Alternatively wait for 15 minutes and then press Zero. The display will show “-0.0-” when the meter is zeroed and ready for measurement.
# 2
• Remove the blank and insert the other cuvette into the instrument.
• Press the Read key and the meter will perform the reading. The instrument displays the results in mg/L of aluminum.
• Press orto access the second level functions.
• Press the Chem Frm key to convert the result in mg/L of Al2O3.
• Press or  to return to the measurement screen.
INTERFERENCES
Interference may be caused by: Iron above 20 mg/L, Alkalinity above 1000 mg/L, Phosphate above 50 mg/L; Fluoride must be absent.
Aluminum
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AMMONIA MEDIUM RANGE
SPECIFICATIONS
Range 0.00 to 10.00 mg/L Resolution 0.01 mg/L Accuracy ±0.05 mg/L ±5% of reading at 25 °C Typical EMC ±0.01 mg/L
Deviation Light Source Tungsten lamp with narrow band interference filter @ 420 nm Method Adaptation of the
Nessler method. The reaction between ammonia and reagents causes a yellow tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93715A-0 First Reagent 4 drops (6 drops for seawater) HI 93715B-0 Second Reagent 4 drops (10 drops for seawater)
REAGENT SETS
HI 93715-01 Reagents for 100 tests HI 93715-03 Reagents for 300 tests
For other accessories see page 72.
MEASUREMENT PROCEDURE
• Select the the
Ammonia MR
Method Selection
section (see page 12).
ASTM Manual of Water and Environmental Technology, D1426-92
method using the procedure described in
,
10 mL
• Fill the cuvette with 10 mL of unreacted sample (up to the mark) and replace the cap.
• Place the cuvette into the holder and close the lid.
• Press the Zero key. The display will show “-0.0-” when the meter is zeroed and ready for measurement.
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Ammonia MR
• Remove the cuvette.
• Add 4 drops of HI 93715A-0 First Reagent (6 drops for seawater analysis). Replace the cap and mix the solution.
• Add 4 drops of HI 93715B-0 Second Reagent (10 drops for seawater analysis). Replace the cap and mix the solution.
• Reinsert the cuvette into the instrument.
• Press Timer and the display will show the countdown prior to the measurement or, alternatively, wait for 3 minutes and 30 seconds and press Read. When the timer ends the meter will perform the reading. The instrument displays the results in mg/L of ammonia nitrogen (NH3-N).
• Press orto access the second level functions.
• Press the Chem Frm key to convert the result in mg/L of ammonia (NH3) and ammonium (NH
+
4
• Press orto return to the measurement screen.
INTERFERENCES
Interference may be caused by: acetone, alcohols, aldehydes, glycine, hardness above 1 g/L, iron, organic chloramines, sulfide, various aliphatic and aromatic amines.
Ammonia MR
20
).
AMMONIA LOW RANGE
SPECIFICATIONS
Range 0.00 to 3.00 mg/L Resolution 0.01 mg/L Accuracy ±0.04 mg/L ±4% of reading at 25 °C Typical EMC ±0.01 mg/L
Deviation Light Source Tungsten lamp with narrow band interference filter @ 420 nm Method Adaptation of the
Nessler method. The reaction between ammonia and reagents causes a yellow tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93700A-0 First Reagent 4 drops (6 drops for seawater) HI 93700B-0 Second Reagent 4 drops (10 drops for seawater)
REAGENT SETS
HI 93700-01 Reagents for 100 tests HI 93700-03 Reagents for 300 tests
For other accessories see page 72.
MEASUREMENT PROCEDURE
• Select the
Method Selection
• Fill the cuvette with 10 mL of unreacted sample (up to the mark) and replace the cap.
Ammonia LR
method using the procedure described in the
section (see page 12).
ASTM Manual of Water and Environmental Technology, D1426-92
,
10 mL
• Place the cuvette into the holder and close the lid.
• Press the Zero key. The display will show “-0.0-” when the meter is zeroed and ready for measurement.
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Ammonia LR
• Remove the cuvette.
• Add 4 drops of HI 93700A-0 First Reagent (6 drops for seawater analysis). Replace the cap and mix the solution.
• Add 4 drops of HI 93700B-0 Second Reagent (10 drops for seawater analysis). Replace the cap and mix the solution.
• Reinsert the cuvette into the instrument.
• Press Timer and the display will show the countdown prior to the measurement or, alternatively, wait for 3 minutes and 30 seconds and press Read. When the timer ends the meter will perform the reading. The instrument displays the results in mg/L of ammonia nitrogen (NH3-N).
• Press orto access the second level functions.
• Press the Chem Frm key to convert the result in mg/L of ammonia (NH3) and ammonium (NH
+
4
• Press orto return to the measurement screen.
INTERFERENCES
Interference may be caused by: acetone, alcohols, aldehydes, glycine, hardness above 1 g/L, iron, organic chloramines, sulfide, various aliphatic and aromatic amines.
Ammonia LR
22
).
BROMINE
SPECIFICATIONS
Range 0.00 to 8.00 mg/L Resolution 0.01 mg/L Accuracy ±0.08 mg/L ±3% of reading at 25 °C Typical EMC ±0.01 mg/L
Deviation Light Source Tungsten lamp with narrow band interference filter @ 525 nm Method Adaptation of the
18th edition
pink tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93716-0 DPD Reagent 1 packet
REAGENT SETS
HI 93716-01 Reagents for 100 tests HI 93716-03 Reagents for 300 tests
For other accessories see page 72.
MEASUREMENT PROCEDURE
• Select the
• Fill the cuvette with 10 mL of unreacted sample (up to the
Bromine
method using the procedure described in the
Method Selection
mark) and replace the cap.
section (see page 12).
Standard Methods for the Examination of Water and Wastewater,
, DPD method. The reaction between bromine and the reagent causes a
10 mL
• Place the cuvette into the holder and close the lid.
• Press the Zero key. The display will show “-0.0-” when the meter is zeroed and ready for
measurement.
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Bromine
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