Hanna Instruments HI 83225 User manual

Instruction Manual
HI 83225
Grow Master
for Nutrient Analyses
This Instrument is in
Compliance with the CE Directiveswww.hannainst.com
MAN83225R1 04/05
www.hannainst.com

Dear Customer,
Thank you for choosing a Hanna product. Please read this instruction
manual carefully before using the meter. 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 [email protected]. These instruments are in compliance
with directives.
PRELIMINARY EXAMINATION ....... 3
GENERAL DESCRIPTION ............... 3
SPECIFICATIONS ......................... 4
PRINCIPLE OF OPERATION .......... 4
FUNCTIONAL DESCRIPTION.......... 6
GUIDE TO DISPLAY CODES .......... 7
TIPS FOR AN ACCURATE
MEASUREMENT ........................ 10
PARAMETERS REFERENCE TABLE 11
OPERATIONAL GUIDE ................ 12
ABBREVIATIONS ....................... 13
INTRODUCTION ........................ 14
SAMPLE PREPARATION .............. 19
AMMONIA LR ........................... 23
AMMONIA MR .......................... 25
AMMONIA HR ........................... 27
CALCIUM .................................. 29
MAGNESIUM ............................ 31
NITRATE LR .............................. 33
NITRATE MR ............................. 35
NITRATE HR ............................. 37
PHOSPHORUS LR ..................... 39
PHOSPHORUS MR .................... 41
PHOSPHORUS HR ..................... 43
POTASSIUM LR ......................... 45
POTASSIUM MR........................ 47
POTASSIUM HR ........................ 49
POTASSIUM UHR ...................... 50
SULFATE .................................. 51
INTERFACE WITH PC ................. 53
STANDARD METHODS ............... 55
BATTERY REPLACEMENT ............ 55
ACCESSORIES ........................... 56
WARRANTY ............................... 57
CE DECLARATION
OF CONFORMITY....................... 58
HANNA LITERATURE .................. 59
Allrightsarereserved.Reproductioninwholeorinpartisprohibitedwithoutthewrittenconsentof
the copyright owner, Hanna Instruments Inc., Woonsocket, Rhode Island, 02895 , USA.
TABLE OF CONTENTS
259
Hanna publishes a wide range of catalogs and handbooks for
an equally wide range of applications. The reference literature
currently covers areas such as:
•Water Treatment
• Process
• Swimming Pools
• Agriculture
• Food
• Laboratory
• Thermometry
and many others. New reference material is constantly being
added to the library.
For these and other catalogs, handbooks and leaflets contact
your dealer or the Hanna Customer Service Center nearest to
you. To find the Hanna Office in your vicinity, check our home
page at www.hannainst.com.
HANNA LITERATURE

3
Remove the instrument from the packing material and examine it
carefully to make sure that no damage has occurred during shipment.
If there is any damage, notify your Dealer.
Each HI 83225 Meter is supplied complete with:
• Four Sample Cuvets and Caps
• One Transport Cap
• Two 9 V Battery
• 12 VDC Transformer (HI 710005 or HI 710006)
Note: Save all packing material until you are sure that the instrument
functions correctly. Any defective item must be returned in its
original packing with the supplied accessories.
HI 83000 Series is a line of 18 different bench, microprocessor-based
photometers that measure more than 50 parameters in water and
wastewater. These multipurpose meters are manufactured to measure
the most important parameters of the application they have been
especially designed for:
HI 83099 Laboratories, with COD HI 83200 Laboratories
HI 83203 Aquaculture HI 83205 Boilers & Cooling Towers
HI 83206 Environmental Testing HI 83207 Industrial Wastewater
HI 83208 Water Conditioning HI 83209 Education
HI 83210 Pulp & Paper Mills HI 83211 Chemical Manufacturers
HI 83212 Power Plant Utilities HI 83213 Municipal Wastewater
HI 83214 Wastewater Treatment Applic. HI 83215 Nutrient Analyses
HI 83216 Pool & Spa Applic. HI 83218 Environmental Applic.
HI 83225 Nutrient Analyses HI 83226 Pool & Spa Applic.
All meters use an exclusive positive-locking system to ensure that the
cuvet is in the same position every time it is placed into the
measurement cell.
The reagents are in liquid or powder form and are supplied in bottles
or in packets. The amount of reagent is precisely dosed to ensure the
maximum repeatability.
Display codes aid the user in routine operations.
The meters have an auto-shut off feature, turning the unit off after 10
minutes of non-use.
The HI 83000 Series can be connected to a personal computer via the
HI 920010 three wire RS 232 cable. The HI 92000 Hanna Windows®
Compatible Software aids the user to manage all test data.
PRELIMINARY EXAMINATION
GENERAL DESCRIPTION
58
Recommendations for Users
Before using these products, make sure that they are entirely suitable for the environment in which
they are used.
Operation of these instruments in residential area could cause unacceptable interferences to radio
and TV equipments, requiring the operator to take all necessary steps to correct interferences.
Any variation introduced by the user to the supplied equipment may degrade the instruments' EMC
performance.
To avoid damages or burns, do not perform any measurement in microwave ovens.
CE DECLARATION OF CONFORMITY

4
Light Source Tungsten lamp with narrow band interference
filter
Light Detector Silicon Photocell
Environment 0 to 50°C (32 to 122°F);
max 95% RH non-condensing
Power Supply 2x 9 V batteries / 12 to 20 VDC through voltage
adapter
Auto-Shut off After 10' of non-use
Dimensions 230 x 165 x 70 mm (9.0 x 6.5 x 2.8")
Weight 640 g (22.6 oz.)
For specifications related to each single parameter (e.g. range, accu-
racy, etc.), refer to the related measurement section.
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, mol-
ecules 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 physico-
chemical characteristics of substance according to the Lambert-Beer
Law:
-log I/Io= ελc d
or
A = ελc 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.
SPECIFICATIONS
PRINCIPLE OF OPERATION
57
All Hanna Instruments meters are warranted for two years against
defects in workmanship and materials when used for their intended
purpose and maintained according to instructions.
This warranty is limited to repair or replacement free of charge.
Damages due to accidents, misuse, tampering or lack of prescribed
maintenance are not covered.
If service is required, contact the dealer from whom you purchased the
instrument. If under warranty, report the model number, date of
purchase, serial number and the nature of the failure. If the repair is
not covered by the warranty, you will be notified of the charges
incurred.
If the instrument is to be returned to Hanna Instruments, first obtain a
Returned Goods Authorization Number from the Customer Service
department and then send it with shipment costs prepaid. When
shipping any instrument, make sure it is properly packaged for com-
plete protection.
To validate your warranty, fill out and return the enclosed warranty
card within 14 days from the date of purchase.
Hanna Instruments reserves the right to modify the design, construc-
tion and appearance of its products without advance notice.
WARRANTY

5
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 83000 multiparameter photometers
is based on special subminiature tungsten lamps and narrow-band
interference filters to guarantee both high performance and reliable
results.
Four measuring channels (at four different wavelengths) allow a wide
range of tests.
HI 83000 Block diagram (optical layout)
A microprocessor controlled special tungsten lamp emits radiation
which is first optically conditioned and beamed to the sample con-
tained in the cuvet. The optical path is fixed by the diameter of the
cuvet. Then the light is spectrally filtered to a narrow spectral band-
width, to obtain a light beam of intensity Ioor I.
The photoelectric cell collects the radiation Ithat is not absorbed by
the sample and converts it into an electric current, producing a poten-
tial 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 cuvet 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) cuvets are optically identi-
cal to provide the same measurement conditions. Whenever possible
use the same cuvet for both.
It is also necessary that the surface of the cuvet is 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
cuvet walls with hands.
Furthermore, in order to maintain the same conditions during the
zeroing and the measuring phases, it is necessary to close the cuvet to
prevent any contamination.
56
REAGENT SETS
HI 93706-01 100 Phosphorus tests
HI 93706-03 300 Phosphorus tests
HI 93715-01 100 Ammonia tests
HI 93715-03 300 Ammonia tests
HI 93728-01 100 Nitrate tests
HI 93728-03 300 Nitrate tests
HI 93750-01 100 Potassium tests
HI 93750-03 300 Potassium tests
HI 93751-01 100 Sulfate tests
HI 93751-03 300 Sulfate tests
HI 937520-01 50 Magnesium tests
HI 937520-03 150 Magnesium tests
HI 937521-01 50 Calcium tests
HI 937521-03 150 Calcium tests
OTHER ACCESSORIES
HI 721310 9V battery (10 pcs)
HI 731318 Tissue for wiping cuvets (4 pcs)
HI 731321 Glass cuvets (4 pcs)
HI 731325N New cap for cuvet (4 pcs)
HI 740034 Cap for 100 mL beaker (6 pcs)
HI 740036 100 mL plastic beaker (6 pcs)
HI 740157 Plastic refilling pipette (20 pcs)
HI 92000 Windows®Compatible Software
HI 920010 PC connection cable
HI 93703-50 Cuvets cleaning solution (230 mL)
HI 740223 170 mL plastic beaker
HI 740224 170 mL plastic beakers (12 pcs)
HI 740225 60 mL graduated syringe
HI 740226 5 mL graduated syringe
HI 740227 Filter assembly
HI 740228 Filter discs (25 pcs)
HI 740229 100 mL Polypropylene cylinder
HI 740230 230 mL Demineralized water
HI 93703-54 Dried resin (100 g)
HI 93703-55 Activated Carbon (50 pcs)
ACCESSORIES

6
FRONT PANEL
1) Cuvet Holder
2) Dual Level Liquid Crystal Display
3) Programs List
4) READ DIRECT, to perform measurement immediately
5) TIMER, to perform measurements after a preprogrammed
countdown
6) ZERO, to zero the meter prior to measurement
7) Program Wand V, to select the desired parameter
8) ON/OFF, to turn the meter on and off
REAR PANEL
1) Power Socket 12V to 20V DC 2.5 Watt
2) RS 232 Socket
3) Batteries Compartment
FUNCTIONAL DESCRIPTION
55
Description Program Range Method
Ammonia, LR 1 0.0 to 10.0 mg/L Nessler
Ammonia, MR 2 0.0 to 50.0 mg/L Nessler
Ammonia, HR 3 0 to 100 mg/L Nessler
Nitrate, LR 4 0.0 to 30.0 mg/L Cadmium Reduction
Nitrate, MR 5 0 to 150 mg/L Cadmium Reduction
Nitrate, HR 6 0 to 300 mg/L Cadmium Reduction
Phosphorus, LR 7 0.0 to 10.0 mg/L Aminoacid
Phosphorus, MR 8 0.0 to 50.0 mg/L Aminoacid
Phosphorus, HR 9 0 to 100 mg/L Aminoacid
Potassium, LR 10 0.0 to 20.0 mg/L Turbidimetric
Potassium, MR 11 10 to 100 mg / L Turbidimetric
Potassium, HR 12 20 to 200 mg / L Turbidimetric
Calcium, 13 0 to 400 mg/L Oxalate
Magnesium, HR 14 0 to 150 mg/L Calmagite
Sulfate 15 0 to 150 mg/L Turbidimetric
Besides to the 12 VDC supply, this meter can also be fed by two 9V
batteries.
To prolong battery life, switch your meter off after use. However, the
meter has an auto-shut off feature that will turn itself off after 10
minutes of non-use.
A blinking "LOBAT" on the display, while a
measurement is in progress, indicates low
voltage and the batteries should be replaced.
If the batteries are not replaced immedi-
ately, in order to prevent erroneous readings
due to low voltage, "-BA-" is displayed soon
afterwards. At this point the batteries must
be changed.
Battery replacement must only take place in a non-hazardous area
using two 9V alkaline batteries.
Remove the battery cover on the back of photometer, attach two fresh
9V batteries, while paying attention to the correct polarity, and
replace the cover.
The meter will turn on automatically when a new battery is connected.
You can turn it off by pressing ON/OFF.
STANDARD METHODS
BATTERY REPLACEMENT

7
Note: The secondary LCD below shows a generic "P– –", whereas the
meter will indicate the exact program number (e.g. "P1" for
Ammonia LR).
Sampling in progress. This flashing prompt
appears each time the meter is perform-
ing a measurement.
The microprocessor is adjusting the light
level, indicated by a scrolling "SIP".
This indicates that the meter is in a zeroed
state and measurement can be performed.
The blinking "LOBAT" indicates that the
battery voltage is getting low and the bat-
teries need to be replaced.
The instrument is performing an internal
check-up.
This indicates that the meter is in a ready
state and zeroing can be performed.
This indicates that the batteries are dead
and must be replaced.
GUIDE TO DISPLAY CODES
54
/PUP - Program Up
/PDN - Program Down
/PTM - Turn Test Mode On
/Brx - Set the baud rate
1 - 300 2 - 600
3 - 1200 4 - 2400
/KBL - Lock Keyboard
/KBU - Unlock Keyboard
?PR# - Send Current Program Number (1 to 12)
?BRQ - Send current baud rate
1 - 150 2 - 300
3 - 600 4 - 1200
5 - 2400
?CNQ - Send Concentration (three bytes)
conc
decimal point
unit
m - ppm b - ppb
t - ppt u - pcu
h - pH
?ERR - send error / status information
0 - No error
1 - CAP
2 - HI
3 - ZERO
4 - LO
5 - IDLE
6 - ZERO DONE
7 - TIMED READ
Excel©Copyright of "Microsoft Co."
Lotus 1-2-3©Copyright of "Lotus Co."
TELIX®is registered Trademark of "Deltacomm"
Windows®and Windows Terminal®are registered Trademark of "Microsoft Co."

8
This indicates that the meter has lost its
configuration. Contact your dealer or the
nearest Hanna Customer Service Center.
ERROR MESSAGESERROR MESSAGES
ERROR MESSAGESERROR MESSAGES
ERROR MESSAGES
a) on zero reading:a) on zero reading:
a) on zero reading:a) on zero reading:
a) on zero reading:
The instrument cannot adjust the light
level. Please check that the sample does
not contain any debris.
There is not enough light to perform a
measurement. Please check the prepara-
tion of the zero cuvet.
This indicates that the zeroing procedure
failed due to a low signal-to-noise ratio. In
this case press ZERO again.
There is too much light to perform a mea-
surement. Please check the preparation of
the zero cuvet.
The lamp is not working properly. Contact
your dealer or the nearest Hanna Customer
Service Center.
The lamp is not working properly. Contact
your dealer or the nearest Hanna Customer
Service Center.
Light over range. The cuvet is not inserted
correctly and an eccess ambient light is
reachingthedetector.If thecuvet isproperly
inserted, then contact your dealer or the
nearest Hanna Customer Service Center.
53
To connect your meter to the PC use the optional HI 920010 (avail-
able from your Hanna Dealer). Make sure that your meter is switched
off and plug the connectors, one into the meter RS 232C socket, the
other into the serial port of your PC.
Note: Cables other than HI 920010 may use a different configura-
tion, in which case, communication between the meter and the PC
may not be possible.
SETTING THE BAUD RATE
The transmission speed (baud rate) of the meter and the external
device must be identical. The meter is factory set to 2400.
If you wish to change this value, please contact your nearest Hanna
Center.
SENDING COMMANDS FROM PC
With terminal programs such as, for example, Telix®, Windows Termi-
nal®, it is possible to remotely control your Hanna Instruments bench
meter. Use HI 920010 cable to connect the meter to the PC, start the
terminal program and set the communication options as follows: 8, N,
1, no flow control.
Command Types
To send a command to the pH meter the scheme is:
<DLE> <command> <CR>
This line makes the computer send a Data Link Escape character (/ or
?), the command expressed as a number or a 3-character sequence
and a CR character.
INTERFACE WITH PC
Note: Windows Terminal®and all the other terminal programs that
support the ANSI escape sequence, represent the DLE character by the
string ‘^P’ and the CR character by the string ‘^M’.
Type of Commands
/OFF - Turn the meter OFF
/PDR - Press Read Direct
/PTR - Press Timer
/PZR - Press Zero

9
A zero reading was not taken. Follow the
instruction described in the measurement
procedures for zeroing the meter.
Under range. A blinking "0.00" indicates
that the sample absorbs less light than the
zero reference. Check the procedure and
make sure that you use the same cuvet for
reference (zero) and measurement.
1) A flashing value of the maximum con-
centration indicates an over range condi-
tion. The concentration of the sample is
beyond the programmed range: dilute the
sample and rerun the test.
2) A flashing value lower than the maxi-
mum concentration indicates a low signal-
to-noise ratio condition. In this case accu-
racy of the result is not guaranteed. Repeat
the reading procedure.
The sample and zero cuvet are inverted.
b) on sample reading:b) on sample reading:
b) on sample reading:b) on sample reading:
b) on sample reading:
There is too much light for the sample
measurement. Please check if the right
sample cuvet is inserted.
• Wait for a few seconds and the
display will show "-0.0-". Now the
meter is zeroed and ready for
measurement.
• Remove the cuvet.
• Add the content of one packet of
93751 reagent
• Replace the cap and shake gently
for 1 minute.
• Reinsert the cuvet into the
instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 5 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L of Sulfate
(SO4
2-) on the Liquid Crystal Display.
INTERFERENCES
Color or suspended matter in large amounts will interfere: suspended
matter should be removed by previous filtration.
Organic matter in large amounts may impede the precipitation of
barium sulfate.
Calcium (as CaCO3) >20000 mg/L
Chloride (as Cl-) >40000 mg/L
Magnesium (as MgCO3) >10000 mg/L
Silica (as SiO2) >500 mg/L
Sulfate 52
12
3
6
9
1’

10
The instructions listed below should be carefully followed during testing
to ensure best accuracy.
• Color or suspended matter in large amounts may cause interference,
therefore, these should be removed by treatment with active carbon
and by prior filtration.
• For a correct filling of the cuvet: the liquid
in the cuvet forms a convexity on the top;
the bottom of this convexity must be at
the same level of the 10 mL mark.
• Proper use of the dropper: to get good re-
producible results, tap the dropper on the
table for several times and wipe the outside
of the dropper tip with a cloth. Always keep
the dropper bottle in a vertical position while
dosing the reagent.
• 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.
10 mL
TIPS FOR AN ACCURATE MEASUREMENT
• It is important that the sample does not contain any debris. This
would corrupt the readings.
• Do not let the reacted sample stand too long after reagent is
added, or accuracy will be lost.
• In order to avoid reagent leaking and to obtain more
accurate measurements, it is recommended to close
the cuvet first with the supplied HDPE
plastic stopper and then with the black cap.
• Each time the cuvet is used, the cap must be tightened
to the same degree.
(a) (b) (c)
SPECIFICATIONS
Range 0 to 150 mg/L
Resolution 5 mg/L
Accuracy ±5 mg/L ±3% of reading
Light Source Tungsten lamp with narrow band interference filter
@ 466 nm
Method Sulfate is precipitated with barium chloride crystals.
Light absorbance of the suspension is measured.
REQUIRED REAGENTS
Code Description Quantity
HI 93751-0 Indicator reagent 1 packet
REAGENT SETS
HI 93751-01 Reagents for 100 tests
HI 93751-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
Note: for sample preparation follow the IRRIGATION WATER (LR)
procedure at page 19.
• Select the program number 15 “Sulfate” on the secondary LCD by
pressing PROGRAM Mand L.
• Fill a cuvet with 10 mL of unreacted
sample (up to the mark) and replace
the cap.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
• Press ZERO and "SIP" will appear on
the display.
SULFATE
Sulfate
51
10 mL

11
• Whenever the cuvet is placed into
the measurement cell, it must be
dry outside, and completely free of
fingerprints, oil or dirt. Wipe it
thoroughly with HI 731318 or a
lint-free cloth prior to insertion.
• 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 cuvet for zeroing and
measurement.
• It is important to discard the sample immediately after the reading
is taken because the glass might become permanently stained.
• All the reaction times reported in this manual are referred to 20°C
(68°F). As a general rule of thumb, they should be doubled at
10°C (50°F) and halved at 30°C (86°F).
HI 83225 - NUTRIENT ANALYSES
Code Parameter Page
1 Ammonia LR 23
2 Ammonia MR 25
3 Ammonia HR 27
4 Nitrate LR 33
5 Nitrate MR 35
6 Nitrate HR 37
7 Phosphorus LR 39
8 Phosphorus MR 41
9 Phosphorus HR 43
Code Parameter Page
10 Potassium LR 45
11 Potassium MR 47
12 Potassium HR 49
13 Calcium 29
14 Magnesium 31
15 Sulfate 51
PARAMETERS REFERENCE TABLE
50
• Wait for a few seconds and the display will
show “-0.0-”. Now the meter is zeroed
and ready for measurement.
• Remove the cuvet and add
the content of one packet
of HI 93750B reagent. Re-
place the cap and mix
gently for one minute by
turning slowly the cuvet up-
side down.
• Reinsert the cuvet into the
instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 2 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L of potassium
(K) on the Liquid Crystal Display.
• To convert the reading to mg/L of potassium oxide (K2O), multiply
by a factor of 1.20.
INTERFERENCES
The following ions do not interfere below the concentrations reported:
Ammonium 10 ppm Calcium 10000 ppm as CaCO3
Chloride 12000 ppm Magnesium 8000 ppm as CaCO3
Sodium 8000 ppm
Potassium HR
For samples containing more than 200 ppm of Potassium: first follow
the sample preparation procedure described at page 21 for NUTRIENTS
SOLUTION (HR). Then add to the graduated cylinder 20 mL of the
prepared sample (for HR) and fill the cylinder with demineralized
water from the Demineralizer Bottle up to the 100 mL mark.
Follow the MEASUREMENT PROCEDURE at page 49.
Read the result in mg/L of Potassium on the display and multiply the
reading by 5 to obtain the real concentration of Potassium in your
sample.
POTASSIUM ULTRA HIGH RANGE

12
POWER CONNECTION
Plug the 12VDC adapter (HI 710005 - 110VDC, or HI 710006 -
220VDC) into the DC socket. Plug the adapter into the outlet.
Alternatively, remove the battery cover on the back of the meter;
attach 2 fresh 9V batteries and replace the cover.
Note:Insure the main line is surge protected.
Note: Always turn the meter off before unplugging it to insure no data
is lost.
MEASUREMENT PROCEDURE
•Turn the meter on by pressing ON/OFF.
•The meter will first perform an LCD self
diagnostic test by displaying a full set of
figures.
• Then it will show a scrolling
"225 Hanna Inst" message.
OPERATIONAL GUIDE
• When the LCD displays “----”, the meter
is ready. On the secondary LCD "P1" will
appear to inform that the first parameter
measurement procedure (Ammonia LR)
can be performed.
•Press the PROGRAM Mand PROGRAM Lkeys to select the
desired parameter.
49
SPECIFICATIONS
Range 20 to 200 mg/L
Resolution 5 mg/L
Accuracy ±30 mg/L ±7% of reading
Light Source Tungsten lamp with narrow band interference
filter @ 610 nm
Method Adaptation of the Turbidimetric Tetraphenylborate
method. The reaction between Potassium and
reagents causes turbidity in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93750AA
AA
A-0 Potassium Reagent 6 drops
HI 93750BB
BB
B-0 Powder Reagent 1 packet
REAGENT SETS
HI 93750-01 Reagents for 100 tests
HI 93750-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
Note: for sample preparation follow the NUTRIENTS SOLUTION (HR)
procedure at page 21.
• Select the program number 12 “Potassium HR” on the secondary
LCD by pressing PROGRAM Mand L.
• Fill the cuvet with 10 mL of sample, up to the
mark.
• Add six drops of HI 93750A,
replace the cap and swirl the
solution.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
• Press ZERO adn “SIP”
will appear on the dis-
play.
10 mL
Potassium HR
POTASSIUM HIGH RANGE
x 6

13
Note: in the following measurement
sections, a generic "P– –" will be placed
on the secondary LCD instead of the exact
related message (e.g. "P1" for Ammonia
LR).
•Before performing a test read carefully all the instructions related
to the selected parameter.
For the program number, see the table on page 11 or look at the list
printed on the mask of the meter.
°C°C
°C°C
°C: degree Celsius
°F°F
°F°F
°F: degree Fahrenheit
HRHR
HRHR
HR: High Range
kg/hakg/ha
kg/hakg/ha
kg/ha: kilograms per hectare
LCDLCD
LCDLCD
LCD: Liquid Crystal Display
LRLR
LRLR
LR: Low Range
L/haL/ha
L/haL/ha
L/ha: liters per hectare
mm/hamm/ha
mm/hamm/ha
mm/ha: millimeters per hectare
mg/Lmg/L
mg/Lmg/L
mg/L: milligrams per liter (ppm)
mLmL
mLmL
mL: milliliter
MRMR
MRMR
MR: Medium Range
UHRUHR
UHRUHR
UHR: Ultra High Range
ABBREVIATIONS
48
• Press ZERO and “SIP” will appear on the display.
• Wait for a few seconds and the display will
show “-0.0-”. Now the meter is zeroed
and ready for measurement.
• Remove the cuvet and add
the content of one packet
of HI 93750B reagent. Re-
place the cap and mix
gently for one minute by
turning slowly the cuvet up-
side down.
• Reinsert the cuvet into the instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 2 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L of potassium
(K) on the Liquid Crystal Display.
• To convert the reading to mg/L of potassium oxide (K2O), multiply
by a factor of 1.20.
INTERFERENCES
The following ions do not interfere below the concentrations reported:
Ammonium 10 ppm
Calcium 10000 ppm as CaCO3
Chloride 12000 ppm
Magnesium 8000 ppm as CaCO3
Sodium 8000 ppm
Potassium MR

14
THE ROLE OF NUTRIENTS IN THE GROWTH AND
PRODUCTION OF PLANTS
The three primary macro elements needed by the plants are nitrogen
(N), phosphorus (P) and potassium (K), while calcium (Ca), magne-
sium (Mg) and Sulfer (S) are so called secondary macro elements. In
hydroponics, plants need a balanced nutritive solution, composed of
both primary and secondary elements.
Shortage or excess of even only one nutritive element may cause an
imbalance in plant physiology and in the absorption of the other
nutrients. Nutrients shortages may result in irregular plant growth, low
resistance to diseases, scarce production both in quantity and quality,
while nutrients excess may cause waste of fertilizer, pollution of the
groundwater and the possible accumulation of dangerous substances
in the crops produced.
INTRODUCTION
NITROGENNITROGEN
NITROGENNITROGEN
NITROGEN
Nitrogen (N) is mostly absorbed by plants as nitrates (NO3
-) and, in
smaller amount, in the form of ammonium (NH4
+). In hydroponics, an
adequate ratio between the two forms is generally used in nutritive
solutions.
PRESENT IN proteins, enzymes, chlorophyll, hormones, vitamins,
DNA and RNA
ACTION • is fundamental for plants in phase of growth
• promotes the lengthening of trunks and sprouts
• increases the production of foliage
• helps to absorb other nutrients
(in particular phosphorus)
• assists a bigger production for both size and
number of fruits
SHORTAGE • slower growth
EFFECTS • smaller leaves
• yellowing of leaves
• smaller fruits
• premature ripening
EXCESS • reduction in resistance to diseases and atmospheric agents
EFFECTS • increase of water demand (caused by an excessive
production of leaves)
• bad quality of fruits
• delayed ripening
• reduction in potassium absorption
47
SPECIFICATIONS
Range 10 to 100 mg/L
Resolution 2.0 mg/L
Accuracy ±15 mg/L ±7% of reading
Light Source Tungsten lamp with narrow band interference
filter @ 610 nm
Method Adaptation of the Turbidimetric Tetraphenylborate
method. The reaction between potassium and
reagents causes turbidity in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93750AA
AA
A-0 Potassium Reagent 6 drops
HI 93750BB
BB
B-0 Powder Reagent 1 packet
REAGENT SETS
HI 93750-01 Reagents for 100 tests
HI 93750-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
Note: for sample preparation follow the NUTRIENTS SOLUTION (MR)
procedure at page 20.
• Select the program number 11 “Potassium MR” on the secondary
LCD by pressing PROGRAM Mand L.
• Fill the cuvet with 10 mL of sample, up to the
mark.
• Add six drops of HI 93750A,
replace the cap and swirl the
solution.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
10 mL
x 6
Potassium MR
POTASSIUM MEDIUM RANGE

15
PHOSPHORUSPHOSPHORUS
PHOSPHORUSPHOSPHORUS
PHOSPHORUS
Phosphorus (P) has an important role in many fundamental biochemi-
cal and physiological processes. Plants take up phosphorus in the form
of phosphate ion (PO4
3-).
PRESENT IN DNA and RNA, ATP, ADP
ACTION • stimulates the roots growth
• stimulates blooming
• stimulates fecundation and ripeness
• strengthens the plant tissues
• is necessary in the formation of seeds
SHORTAGE • delayed ripening
EFFECTS • slower growth
• small leaves
• decrease of production (smaller fruits and difficult
seeds formation)
• reduction of root system
EXCESS EFFECTS • premature ripening
• excess of fruit-setting
• negative effects on the absorption of some micro-
elements such as iron, zinc, boron and copper
POTASSIUMPOTASSIUM
POTASSIUMPOTASSIUM
POTASSIUM
Potassium (K) is essential in proteic synthesis. The problem of lack of
potassium is quite frequent in calcareous soils.
Potassium is absorbed as K+.
PRESENT IN tissues responsible for the growth of plants (primary
and secondary meristems), embryos and cell vacuole
ACTION • improves the quality of fruits and flowers
• gives more resistance both to frost and to
diseases caused by fungi (increases the cuticular
thickness)
• regulates the cellular turgidity (helps to regulate the
osmotic processes and increases the resistance to
dryness)
• regulates the stomatic opening and closing (it means
a strong influence on transpiration and photo-
synthesis)
SHORTAGE • slower growth
EFFECTS • smaller fruits, less colored and less preserved
• increase of transpiration
• less resistance to the cold
46
• Press ZERO and “SIP” will appear on the display.
• Wait for a few seconds and the display will
show “-0.0-”. Now the meter is zeroed and
ready for measurement.
• Remove the cuvet and add
the content of one packet
of HI 93750B reagent. Re-
place the cap and mix
gently for one minute by
turning slowly the cuvet up-
side down.
• Reinsert the cuvet into the instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 2 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L of potassium
(K) on the Liquid Crystal Display.
• To convert the reading to mg/L of potassium oxide (K2O), multiply
by a factor of 1.20.
INTERFERENCES
The following ions do not interfere below the concentrations reported:
Ammonium 10 ppm
Calcium 10000 ppm as CaCO3
Chloride 12000 ppm
Magnesium 8000 ppm as CaCO3
Sodium 8000 ppm
Potassium LR

EXCESS EFFECTS • reduced absorption of calcium and magnesium
• increase of water consumption
• increase of the substrate salinity
16
MAGNESIUMMAGNESIUM
MAGNESIUMMAGNESIUM
MAGNESIUM
Magnesium (Mg) is essential for the formation of chlorophyll and it
stimulates the absorption of phosphorus by plants.
PRESENTIN chlorophyll
ACTION •it acts similar like calcium
•is present in chlorophyll and pectin
•it stimulates absorption of phosphourus
SHORTAGE •interveinal chlorosis which first develops in older
EFFECTS leaves
•small veins and not green
•severe starvation, older leaves shrivel and die
EXCESSEFFECTS •very little information available on visual symptoms
CALCIUMCALCIUM
CALCIUMCALCIUM
CALCIUM
Calcium (Ca) forms a structural part of the plant cell walls. It helps to
build up resistance against fungus and bacteriological attack.
PRESENTIN tissue of cell walls
ACTION • it gives rigidity or stiffness to plant stems
• it stimulates roots growth
• neutralizes organic acids like oxalic and succinic acid
• regulates the absorption of potassium, magnesium
etc.
SHORTAGE • young leafs become distorted
EFFECTS • bud development is inhibited
• root tips often die
• plant growth stunted with short internodes
EXCESSEFFECTS • no consistent visual symptoms, usually associated
with excess carbonates
45
SPECIFICATIONS
Range 0.0 to 20.0 mg/L
Resolution 0.5 mg/L
Accuracy ±3.0 mg/L ±7% of reading
Light Source Tungsten lamp with narrow band interference
filter @ 610 nm
Method Adaptation of the Turbidimetric Tetraphenylborate
method. The reaction between potassium and
reagents causes turbidity in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93750AA
AA
A-0 Potassium Reagent 6 drops
HI 93750BB
BB
B-0 Powder Reagent 1 packet
REAGENT SETS
HI 93750-01 Reagents for 100 tests
HI 93750-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
Note: for sample preparation follow the IRRIGATION WATER (LR)
procedure at page 19.
• Select the program number 10 “Potassium LR” on the secondary
LCD by pressing PROGRAM Mand L.
• Fill the cuvet with 10 mL of sample, up to the
mark.
• Add six drops of HI 93750A,
replace the cap and swirl the
solution.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
10 mL
x 6
Potassium LR
POTASSIUM LOW RANGE

17
SULPHURSULPHUR
SULPHURSULPHUR
SULPHUR
Sulphur (S) is a constituent of plant proteins and hormones. Plants
take up sulphur in the form of sulphate ions (SO4
2-).
PRESENTIN proteins, hormones, vitamins and essential oils
ACTION •plant metabolism
•stimulates absorption of atmospheric nitrogen
SHORTAGE •upper leaves remain small, and curl downward
EFFECTS •yellowing of younger leaves
EXCESSEFFECTS •reduction of growth and leave size
•leave symptoms often absent or poor defined
•sometimes interveinal yellowing and burning
44
Phosphorus HR
INTERFERENCES
Calcium above 10000 mg/L as CaCO3
Chloride above 150000 mg/L as Cl–
Ferrous iron above 100 mg/L
Magnesium above 40000 mg/L as CaCO3
Sulfide
x 10
• Wait for a few seconds and the
display will show "-0.0-". Now
the meter is zeroed and ready for
measurement.
• Remove the cuvet.
• Add 10 drops of HI 93706A
Molybdate reagent.
• Add the content of one packet of
HI 93706B Phosphorus Reagent
B (Amino Acid) to the cuvet.
Replace the cap and shake gently
until dissolution is complete.
• Reinsert the cuvet into the
instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 5 minutes and press READ
DIRECT. In both cases "SIP" will blink during measurement.
• The instrument directly displays concentration in mg/L of phosphorus
(P) on the Liquid Crystal Display.
• To convert the reading to mg/L of phosphate (PO4
3–), multiply by
a factor of 3.07.

18
NUTRIENTS SOLUTIONS (MEDIUM AND HIGH RANGE)NUTRIENTS SOLUTIONS (MEDIUM AND HIGH RANGE)
NUTRIENTS SOLUTIONS (MEDIUM AND HIGH RANGE)NUTRIENTS SOLUTIONS (MEDIUM AND HIGH RANGE)
NUTRIENTS SOLUTIONS (MEDIUM AND HIGH RANGE)
The nutrients requirements of the plants are determined by the type of
plant, its age and the environmental conditions. The control of chemi-
cal composition of nutrients solutions given to the plants is an operation
that allows a correct preparation of the fertilizer. In analyzing the
solution, it is possible to choose between medium range and high
range values, depending on the concentration of substances.
Medium range usually covers the analysis of residual solutions in
recycling systems. The nutritive elements are differently absorbed by
the plants, hence the nutrient solution loses substances, becomes
impoverished and must be enriched.
High range normally corresponds to the typical values of nutrients
solutions. It is therefore possible to verify that the solution given to the
plants contains the correct quantities of nutritive substances.
WATER AND NUTRIENT MANAGEMENT
IRRIGATION WATER (LOW RANGE)IRRIGATION WATER (LOW RANGE)
IRRIGATION WATER (LOW RANGE)IRRIGATION WATER (LOW RANGE)
IRRIGATION WATER (LOW RANGE)
In agricultural areas it is quite common to find altered values in the
chemical composition of irrigation waters. The problem concerns mostly
the high nitrate concentration, usually determined by excessive fertili-
zation or irrational liquid manure spreading. The analysis of irrigation
waters allows us to find out which are the substances present in major
or minor quantity and to organize an advantageous fertilization plan.
For example, if the quantity of water utilized for crop cultivation is 250
mm/ha (= 2500000 L/ha) and the nitrate (NO3
-) concentration is
150 mg/L (34 mg/L as nitrate-nitrogen NO3-N), soil receives 85 kg/
ha of nitrogen. In choosing type and quantity of fertilizer to be used, it
is important to consider this information, in order not to waste fertilizer
nor to induce soil pollution.
43
SPECIFICATIONS
Range 0 to 100 mg/L
Resolution 1 mg/L
Accuracy ±5 mg/L ±4% of reading
Light Source Tungsten lamp with narrow band interference
filter @ 525 nm
Method Adaptation of the Standard Methods for the
Examination of Water and Wastewater, 18th
edition, Amino Acid method. The reaction be-
tween phosphorus and reagents causes a blue
tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93706A-0 Molybdate 10 drops
HI 93706B-0 Amino Acid Powder 1 packet
REAGENT SETS
HI 93706-01 Reagents for 100 tests
HI 93706-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
Note: for sample preparation follow the NUTRIENTS SOLUTION (HR)
procedure at page 21.
Phosphorus HR
PHOSPHORUS HIGH RANGE
• Select the program number 9 “Phosphorus HR” on the secondary
LCD by pressing PROGRAM Mand L.
• Fill the cuvet with 10 mL of unreacted
sample (up to the mark) and replace
the cap.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
• Press ZERO and “SIP” will blink on
the display.
10 mL

LIST OF MATERIAL
Each instrument HI 83225 is supplied with the following accessories
for sample preparation:
• 4 cuvettes (10 mL);
• 2 plastic beakers (100 and 170 mL);
• 1 graduated cylinder (100 mL);
• 1 syringe with screw rim (60 mL)
• 1 syringe (5 mL);
• 1 filter assembly;
• 25 filter discs;
• 1 spoon;
• 2 pipettes;
• Carbon powder packets (50 pcs);
• 1 Demineralizer Bottle with filter cap for about 12 liters of
deionized water (depending on the hardness level of water to
be treated).
SAMPLE PREPARATION PROCEDURE
Note: If the water sample to be analyzed is very turbid, let it stand in
a beaker for a while until most of the solid particles have
settled. Then, use the pipette to transfer the supernatant solu-
tion to the other beaker and prepare the samples as described
below. During this operation, take care not to induce air bubbles
into the solution, in order not to displace the settled solids at
the bottom of the beaker.
IRRIGATION WATER (LR):
• Measure with the graduated cylinder about 100 mL of
sample.
• If the solution contains
some turbidity or color,
pour it in the large
170mL beaker and
add a powder packet
of active carbon.
SAMPLE PREPARATION
19
42
Phosphorus MR
x 10
• Wait for a few seconds and the
display will show "-0.0-". Now
the meter is zeroed and ready for
measurement.
• Remove the cuvet.
• Add 10 drops of HI 93706A
Molybdate reagent.
• Add the content of one packet of
HI 93706B Phosphorus Reagent
B (Amino Acid) to the cuvet.
Replace the cap and shake gently
until dissolution is complete.
• Reinsert the cuvet into the
instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 5 minutes and press READ
DIRECT. In both cases "SIP" will blink during measurement.
• The instrument directly displays concentration in mg/L of phosphorus
(P) on the Liquid Crystal Display.
• To convert the reading to mg/L of phosphate (PO4
3–), multiply by
a factor of 3.07.
INTERFERENCES
Calcium above 10000 mg/L as CaCO3
Chloride above 150000 mg/L as Cl–
Ferrous iron above 100 mg/L
Magnesium above 40000 mg/L as CaCO3
Sulfide

20
filter
disc
• Mix well using the spoon
and then wait for 5
minutes.
• Unscrew the filter assembly,
put a filter disc inside and
close it again.
• Connect the filter assembly
to the 60 mL syringe by
the screw rim.
• Take off the syringe
plunger and fill the syringe
with the sample to be
filtered. Pour the sample
gently, trying to avoid
transferring of the actived
carbon to the syringe.
• Reinsert the plunger and
filter the solution into the
100mL beaker by pushing
gently the syringe plunger.
The sample is now ready.
Note: Filter at least 40 mL of solution if all the four parameters
have to be tested. If the solution is still turbid or colored, treat it
again with a packet of active carbon. After use, throw the filter
disc away and wash the syringe and the filter assembly well.
Always use a new disc for another sample.
NUTRIENTS SOLUTION (MR):
• Use the graduated cylinder to measure exactly 20 mL
of sample.
41
SPECIFICATIONS
Range 0.0 to 50.0 mg/L
Resolution 0.5 mg/L
Accuracy ±2.5 mg/L ±4% of reading
Light Source Tungsten lamp with narrow band interference
filter @ 525 nm
Method Adaptation of the Standard Methods for the
Examination of Water and Wastewater, 18th
edition, Amino Acid method. The reaction be-
tween phosphorus and reagents causes a blue
tint in the sample.
REQUIRED REAGENTS
Code Description Quantity
HI 93706A-0 Molybdate 10 drops
HI 93706B-0 Amino Acid Powder 1 packet
REAGENT SETS
HI 93706-01 Reagents for 100 tests
HI 93706-03 Reagents for 300 tests
For other accessories see page 56.
MEASUREMENT PROCEDURE
• Select the program number 8 “Phosphorus MR” on the secondary
LCD by pressing PROGRAM Mand L.
• Fill the cuvet with 10 mL of unreacted
sample (up to the mark) and replace
the cap.
• Place the cuvet into the holder and
ensure that the notch on the cap is
positioned securely into the groove.
• Press ZERO and “SIP” will blink on
the display.
Note: for sample preparation follow the NUTRIENTS SOLUTION (MR)
procedure at page 20.
Phosphorus MR
PHOSPHORUS MEDIUM RANGE
10 mL