Hanna Instruments HI 93703 User manual

1
Instruction Manual
HI 93703
Portable Microprocessor
Turbidity Meter
99 Washington Street
Melrose, MA 02176
Phone [phone]
Toll Free 1-800-517-8431
Visit us at www.TestEquipmentDepot.com

32
With HI 93703 turbidity measurements can be
performed with high precision in the field as well
as in the laboratory.
HI 93703 turbidity meter is a portable,
microprocessor-based instrument used to
determine the turbidity of water and wastewater.
The meter covers a 0 to 1000 FTU range in two
scales: 0.00 to 50.00 FTU and 50 to 1000 FTU.
The auto-ranging feature sets the appropriate
range for the measurement.
HI 93703 has been designed according to
the ISO7027 International Standard,
consequently the turbidity unit is the FTU
(Formazine Turbidity Unit). FTU is
equivalent to the other internationally
recognized unit: NTU (Nephelometric
Turbidity Unit).
GENERAL DESCRIPTION
Dear Customer,
Thank you for choosing a HANNA instruments®
product.
Please read this instruction manual carefully
before using the instrument.
This manual will provide you with all the neces-
sary information for the correct use of the
instrument.
This instrument is in compliance with the
directives.
TABLE OF CONTENTS
Preliminary examination ............................. 3
General description .................................... 3
Principle of operation .................................. 5
Functional description ................................ 6
Specifications ............................................ 7
Operational guide ....................................... 8
Measurement procedure ........................ 8
How to ensure accurate measurements ... 11
Sources of interferences ...................... 12
Calibration ................................................ 13
Calibration procedure .......................... 13
How to ensure accurate calibration...... 16
Standard suspension .......................... 17
Viewing the calibration date ................ 17
Battery replacement ................................. 18
LCD and error messages .......................... 20
Accessories ............................................. 22
Warranty .................................................. 22
CE declaration of conformity .................... 23
PRELIMINARY EXAMINATION
Remove the instrument from the packing material
and examine it to make sure that no damage has
occurred during shipping. If there is any damage,
notify your dealer.
HI 93703 is supplied complete with:
•Glass cuvet with cap
•Batteries (4 x 1.5V AA) and instructions
HI 93703C is a complete kit supplied with:
•2 glass cuvets with caps
•Batteries (4 x 1.5V AA) and instructions
• HI 93703-0 & HI 93703-10 cal. solutions
• HI 93703-50 cleaning solution
•Tissue for wiping cuvets
•Rugged carrying case
Note: Save all packing material until you are
sure that the meter functions correctly.
All defective items must be returned in
its original packaging with the supplied
accessories.

54
IR LED
EMITTED LIGHT (890 nm)
CUVET
LIGHT
DETECTOR
90° SCATTERED
LIGHT
PRINCIPLE OF OPERATION
* 1 FTU = 1 NTU
HI 93703 has been designed to perform mea-
surements according to the ISO 7027 Interna-
tional Standard.
The instrument functions by passing a beam of
infrared light through a vial containing the sample
being measured.
The light source is a High Emission Infrared
LED with a wavelength peaking at 890 nm,
ensuring that the interference caused by col-
ored samples is minimum.
A sensor, positioned at 90° with respect to the
direction of light, detects the amount of light
scattered by the undissolved particles present
in the sample. The microprocessor converts
such readings into FTU* values.
As noted above, FTU unit is equal to the NTU
unit. However, there are other known measure-
ment units for turbidity: Jackson Turbidity Unit
(JTU) based on the old method of Jackson's
candle, and Silica Unit (mg /L of SiO2). For your
reference the conversion table between these
measurement units is shown below:
JTU FTU/NTU SiO2 (mg/ L)
JTU 1 19 2.5
FTU/NTU 0.053 1 0.13
SiO2 (mg / L) 0.4 7.5 1
* 1 FTU = 1 NTU
The meter housing is a rugged and lightweight
case, with an easy-to-read LCD.
To save battery-life, the instrument is equipped
with an automatic shut-off feature which is
activated after 4 minutes of non-use.
The meter is very simple to use: all operations
can be carried out with only four keys and
troubleshooting functions can be performed with
displayed error code guides.
An exclusive positive-locking system guaran-
tees that the cuvet is firmly placed in the cell.
The keypad is water-resistant and can be wiped
with a moist cloth for quick cleanups.
The one-point calibration at 10 FTU* can be
easily performed using the available stan-
dard. In addition, HI 93703 is the first por-
table turbidity meter that allows to store the
last calibration date and to retrieve it at the
user’s convenience.
HANNA instruments has chosen 10 FTU * as
the calibration point because it is the value
that best fits the water turbidity measure-
ments in different applications, from drink-
ing water to wastewater treatment.
HANNA instruments uses the primary standard
AMCO-AEPA-1 to avoid all formazine-related
problems. Formazine is a very toxic, unstable
substance, which requires particular care: its
standards have to be prepared only a few min-
utes before performing the calibration, and can-
not be reused because of their short life. Hanna
Instruments standards are extremely stable,
can be reused, and last up to six months, if free
from contamination.
HI 93703 can be used with both standards.

76
SPECIFICATIONS
* 1 FTU = 1 NTU
Range 0.00 to 50.00 FTU *
50 to 1000 FTU *
Resolution 0.01 and 1 FTU *
Accuracy ±0.5 FTU* or
±5% of reading (whichever is greater)
Typical EMC Deviation ±2% FS
Calibration 3 point (0, 10 and 500 FTU*)
Light Source Infrared LED
Light Source Life Life of the instrument
Light Detector Silicon Photocell
Battery Type 4 x 1.5V AA alkaline
Battery Life Approx. 60 hours of use
or 900 measurements
Auto-off After 5 minutes of non-use
Environment 0 to 50°C (32 to 122°F);
RH max 95% non-condensing
Dimensions 220 x 82 x 66 mm
(8.7 x 3.2 x 2.6")
Weight 510 g (1.1 lb.)
3
45
6
2
1
FUNCTIONAL DESCRIPTION
1) Measurement cell
2) LCD (Liquid Crystal Display)
3) ON/OFF key
4) CAL key, to enter the calibration mode
5) READ/⇑ key, to perform measurements and
to set the date (day and month) of the last
calibration
6) DATE/⇒ key, to display the last calibration
date and to select either the month or the
day of last calibration

98
•Wipe the cuvette thor-
oughly with a lint-free
tissue (HI 93703-70)
before inserting into
the measurement
cell. The cuvette
must be completely
free of fingerprints
and other oil or dirt,
particularly in the
area where the light
goes through (ap-
proximately the bot-
tom 2 cm/1 inch of
the cuvette).
•Place the cuvette
into the cell and
check that the notch
on the cap is posi-
tioned securely into
the groove.
• The mark on the
cuvette cap should
point towards the
LCD.
•Press the READ/⇑
key and the LCD will
display a blinking
“SIP” (Sampling in
Process). The tur-
bidity value will ap-
pear after approxi-
mately 25 seconds.
OPERATIONAL GUIDE
To prepare the instrument for taking
measurements, first install the batteries (see
Battery Replacement section on page 17) and
then turn the instrument on.
To maximize the battery life the meter is
automatically switched off after 5 minutes of
non-use. To reactivate it, simply press the ON/
OFF key.
MEASUREMENT PROCEDURE
•Turn the meter on by
pressing the ON/OFF
key.
•The meter will carry
out a self-test display-
ing a full set of figures.
After the test, the LCD
will change to the mea-
surement mode.
•When the LCD dis-
plays “----” the meter
is ready to measure.
•Fill a clean cuvette up
to one quarter inch
(0.5 cm) from its rim
with the thoroughly
agitated sample.
•Allow sufficient time for bubbles to escape
before securing the cap.

1110
HOW TO ENSURE ACCURATE MEASURE-
MENTS
•Each time the cuvette is used, tighten the
cap to the same degree.
•Discard the sample soon after the reading is
taken to avoid permanently clouding the glass.
•All glassware used to contain the standards
and the samples should be maintained clean,
washed with HI 93703-50 cleaning solution
and rinsed with HI 93703-0 or turbidity-free
water.
• Collect the samples in clean glass or plastic
bottles, fit stoppers and perform the analysis
quickly. If unavoidable, store the sample in
a cool, dark place, but not for longer than 24
hours (the sample needs to be kept at room
temperature prior to the analysis).
• To obtain a representative sample, gently,
but thoroughly, mix it before samples are
taken. Do not shake (to prevent air bubbles)
and do not let the sample settle.
• It is recommended to monthly calibrate the
meter with the supplied HI 93703-10 @10
FTU* standard or more frequently for greatest
accuracy.
•Before inserting vials
into the instrument,
wipe them with HI
93703-70 soft, lint-free
tissue. Handle vials so
that no fingerprints can
get on the areas
where light passes (ap-
proximately 2 cm/1
inch from the bottom
of the vial).
If you experience any problems in taking mea-
surements, please contact your dealer or the
nearest Hanna Instruments Customer Service
Department.
* 1 FTU = 1 NTU* 1 FTU = 1 NTU
• Even though HI93703 covers a very wide
range of turbidity values, for very accurate
measurements of samples exceeding
40 FTU*, Standard Methods require dilu-
tion. In such cases, the correct amount of
HI 93703-0 or turbidity-free water to be
added to the sample can be calculated
as follows:
Vos = 3000 / T
where: Vos = volume of sample (mL) to be
combined with HI 93703-0 to
obtain the final volume of 100
mL.
T = HI 93703 reading (exceeding
40FTU*)
E.g.: HI 93703 reading = 200 FTU *
3000 / 200 = 15 mL (Vos)
15 mL (Vos)+85 mL (HI 93703-0) = 100
mL
At this point, take a sample of this solution
and measure turbidity.
The correct turbidity value of the original
sample will be:
Tn x 100 mL / Vos = Ta
where: Tn = new HI 93703 reading
Ta = actual turbidity value of the original
sample

1312
CALIBRATION
A monthly calibration is recommended. To
check the date of last calibration, simply hold
the DATE/⇒ key down for few seconds.
A more frequent check of the instrument is
suggested by using the supplied standard solu-
tion.
CALIBRATION PROCEDURE
•Turn the meter on and
wait for the display to
show "----".
•Press the CAL key
once, the "CAL" mes-
sage will blink on the
display for about 6
seconds, then the
calibration mode
stops.
•While the "CAL" mes-
sage is still blinking,
press CAL again. The
instrument is now in
the calibration mode
and a "CL" will ap-
pear on the lower part
of the display. The
date of calibration can
be edited now by sim-
ply pressing the
DATE/⇒ key. To
scroll to the correct
number press the
READ/⇑key. The de-
fault blinking param-
eter is the month, on
the left hand of the
display (MM.DD).
SOURCES OF INTERFERENCE
•Presence of floating debris and coarse sedi-
ments which settle out rapidly will give false
readings.
•The infrared light source used for HI 93703
turbidity meter, according to ISO 7027 Inter-
national Standard, can effectively minimize
errors due to colored dissolved substances.
This effect, named "true color", is a common
interference for most commercially available
instruments operating in the range of visible
light.
•Air bubbles and the effect of vibrations that
disturb the surface of the sample will give
false results.
•Dirty glassware could also affect readings
along with scratched or edged vials.

1514
•Insert the cuvette with
the HI 93703-10
AMCO-AEPA-1 stan-
dard @10 FTU* into
the measurement cell
and press the CAL key
again.
•After the second cali-
bration point (10.00
FTU*) has been ac-
cepted, the meter will
display “500”, asking
for the 500 FTU* solu-
tion to be placed in
the cuvet holder.
Note: At this point the user can exit the
calibration mode and save the two-point
calibration by pressing READ.
To perform a three-point calibration, place the
500 FTU* standard solution in the cuvet holder.
•Press CAL: “SIP” and
“CL” will start blink-
ing.
•After approximately
30 seconds, the dis-
play will show "----".
Now the meter is calibrated and ready for use.
Note: If "ERR1" is displayed, the calibration
data are maintained
•To confirm the dis-
played data values
and to go to the next
step, press the CAL
key once. A blinking
"ZERO" message will
appear.
•Take the HI 93703-0
bottle containing the
ZERO FTU* Standard
(or turbidity-free dilu-
tion water) and fill the
measurement cu-
vette.
Note: In order to minimize any error intro-
duced by the cuvette, it is recommended
to use, during calibration, the same cu-
vette you are going to use to perform the
measurement.
•Insert the cuvette with
the HI 93703-0 @
ZERO FTU* standard
solution (or turbidity-
free dilution water)
into the measurement
cell and press the
CAL key. A blinking
"SIP" message indi-
cates that the instru-
ment is performing
the measurement. Af-
ter approximately 50
seconds the instru-
ment will ask for the
HI 93703-10 standard
solution @10 FTU*
by displaying "10.0".
•Repeat the same procedure with HI 93703-
10 @10FTU* standard solution.
sip
cl
500
cl
* 1 FTU = 1 NTU

1716
STANDARD SUSPENSION
Presently, there are only two recognized pri-
mary standards: AMCO-AEPA-1 and formazine.
HANNA instruments supplies HI 93703 with the
AMCO-AEPA-1 which has a much longer shelf
life at all concentrations (approximately six
months, if free from contamination). In addition,
no special handling or disposal is required and
a much higher stability of suspended particles
has been observed.
On the other hand, formazine is a very toxic
substance, generated by a known carcinogen,
its stability is poor (particles flocculate and
settle quickly). Lower concentrations change
value within a few days or hours after dilution
from stock solutions.
The consistency of HI 93703 readings by using
both standards has been separately estab-
lished by Advanced Polymer Systems and
HANNA instruments.
Additional documentation about the formazine
standard and more complex calibration proce-
dures is available upon request.
VIEWING THE CALIBRATION DATE
•Turn the meter on and
wait for the display to
show "----".
•Press and hold the
DATE/⇒ key and a
"MM.DD" message
appears while the key
is held.
Note: The displayed date is the date that was
input by the user at the beginning of the
last calibration.
HOW TO ENSURE ACCURATE CALIBRA-
TION
The instructions listed below should be carefully
followed during testing and during calibration:
•All glassware that comes into contact with
standards should be maintained clean. Wash
with HI 93703-50 cleaning solution and rinse
with HI 93703-0 or turbidity free water.
•Rinse the vial twice with 5 ml of the liquid to
be tested. This removes the effect of any
previous liquid and any dust or foreign matter
that may be present inside. Gently pour the
liquid down the side of the vial to reduce air
bubbles (no mixing is required when HI 93703-
0 and HI 93703-10 AMCO-AEPA-1 stan-
dards are used).
•Before inserting the vial
into the instrument,
wipe it with HI 93703-
70 soft, lint-free tissue.
Handle vials so that no
fingerprints can get on
the areas where light
passes (approx. 2 cm/
1'' from the bottom of
the vial ) .

1918
Battery replacement must only take place in a
safe area and using the battery types specified
in this instruction manual.
To install or replace the
batteries, turn the unit off
and unscrew the 2 screws
located on the back of the
meter.
Remove the battery cover
and insert the new batteries
in the compartment while
paying attention to the po-
larity.
After the batteries have
been installed, close the
battery cover and tighten
the 2 screws.
BATTERY REPLACEMENT
All components have been selected to mini-
mize current drain without compromising func-
tionality.
In order to minimize the battery consumption,
the meter is equipped with an auto-off function
which switches the meter off after 5 minutes of
non-use.
The power source are 4 alkaline batteries (1.5V
AA) with an expected life of 60 hours, or 900
measurements.
To always grant accurate measurements, the
batteries are monitored to ensure that readings
are not taken when there is insufficient power.
A "LO BAT" indication will appear on the lower
right corner of the display when the batteries are
weak and require replacement. The instrument
can still perform approx. 50 measurements.
A "-BA-" indication will appear on the display
when the batteries are too weak to perform
reliable measurements. The message appears
for a few seconds, and then the meter will
automatically switch off. Batteries must be
immediately replaced.