Hanna Instruments HI 9146 User manual

Instruction Manual
HI 9146
Portable Waterproof
Microprocessor
Dissolved Oxygen Meter
www.hannainst.com

23
DearCustomer,
ThankyouforchoosingaHannaProduct.
Please read this instruction manual carefully
beforeusingtheinstrument.
Thismanualwillprovideyouwiththenecessary
informationforacorrectuseoftheinstrument,
as well as a precise idea of its versatility.
If you need more technical information, do not
hesitatetoe-mailusat[email protected]
Thismeterisincompliancewith directives.
PreliminaryExamination ............................. 3
GeneralDescription..................................... 3
FunctionalDescription-Probe .................... 4
FunctionalDescription-Meter..................... 5
Specifications ............................................. 6
ProbePreparation ....................................... 7
Calibration................................................... 8
Measurement ............................................ 10
AltitudeCompensation .............................. 12
SalinityCompensation .............................. 13
Probe&MembraneMaintenance .............. 14
BatteryReplacement ................................ 16
Accessories.............................................. 17
Warranty ................................................... 18
CEDeclarationofConformity .................... 19
PRELIMINARYEXAMINATION
Removetheinstrumentfromthepackingmaterial
and examine it to make sure that no damage
has occurred during shipping. If there is any
damage,notifyyourDealer.
The meter is supplied complete with:
• HI76407/4FDOprobewith4mcable and
protectivesleeveforHI9146-04
• HI76407/10FDOprobewith10mcable &
protectivesleeveforHI9146-10
•2membranes(HI76407A)withO-rings
•protectivecap
•30 mL electrolyte solution (HI 7041S)
•4 x 1.5V AA batteries
•instructionmanual
•ruggedcarryingcase
Note: Save all packing material until you are
sure that the instrument functions
correctly. Any defective items must be
returnedin theoriginal packingwith the
suppliedaccessories.
GENERAL DESCRIPTION
The Hanna HI 9146 is a water-resistant,
microprocessor-based, auto-calibrating
DissolvedOxygenmeterwithATC. Ithasbeen
developedfordissolvedoxygen andtemperature
measurementinwaterandwastewateraswell
as other applications such as fish farming.
Dissolvedoxygenisindicatedinhundredthsof
parts per million (ppm=mg/L) or in % of
saturation.
Thetemperaturerangeisindicatedincentigrade
from0 to 50°Cwith 0.1°Cresolution.
The ppm and the % saturation are both
compensatedforchangesinsolubilityofoxygen
inwaterandforpermeabilityofthemembrane
aswell as the temperature effect.
TABLE OF CONTENTS

45
FUNCTIONAL DESCRIPTION - PROBE
9
1
3
4
4
5
6
7
8
9
2
10
8
7
6
1. D.O. Probe
2. Protective Cap
3. Watertight Shielded
Cable
4. Polypropylene
Probe Body
5. Temperature Sen-
sor
6. O-Ring Seal
7. AgCl Anode (sensor
element)
8. Platinum Cathode
(sensor element)
9. Oxygen Permeable
Teflon Membrane
10. Membrane Protec-
tive Cap
FUNCTIONAL DESCRIPTION - METER
1) Battery Compartment
2) Probe Connector
3) Liquid Crystal Display
4) ON/OFF key
5) CAL key (to enter/exit calibration mode)
6) FACTOR key (to select altitude F1 and
salinity F2)
7) UP and DOWN arrow keys (to select F1
and F2 levels)
8) HOLD key (to freeze displayed value)
9) RANGE key (to select ppm or % of
saturation)
10) Power socket for 12 Vdc adapter
19) LOW BAT indicator
20) SAMPLE indicator (to indicate measure-
ment mode)
21) F1 indicator (altitude factor)
22) F2 indicator (salinity factor)
23) % or ppm mode indicator
24) Temperature and factor display
Salinity compensation in water allows
determination of mg/L of dissolved oxygen in
salty waters and the altitude compensation
readjustsforthealtitudevariance.
Four 1.5V AA alkaline batteries provide power
and make the instrument completely portable.
HI 9146isalsodesignedtobeusedwithabattery
recharger or a 12 Vdc power supply. A 12 Vdc
input jack is incorporated into the housing.
A microprocessor ensures an accurate and
rapid calibration and measurement. The case
rugged and water-resistant for maximum
protectioninthefieldaswellasinthelaboratory.
Thedissolved oxygenprobe hasa membrane
covering the polarographic sensor elements
and a built-in thermistor for temperature
measurement and compensation. The thin
permeable membrane isolates the sensor
elements from the testing solution, but allows
oxygen to enter. When a voltage is applied
acrossthesensor,oxygenthatpassesthrough
the membrane causes a current to flow from
whichtheoxygenconcentrationisdetermined.

67
PROBE PREPARATION
All probes are shipped dry by Hanna Instru-
ments. To hydrate the probe and prepare it
for use, connect it to the meter and proceed
as follows.
1 Remove the red and black plas-
tic cap which is for shipping
purposes and can be discarded.
2 Wet the sensor by soaking the
bottom 2½ cm (1") of the probe
in electrolyte (HI 7041S) for 5
minutes.
3 Take a membrane
(HI 76407A sup-
plied with the
meter) and Make
sure that the rub-
ber O-ring sits
properly inside
the membrane
cap.
4 Rinse the mem-
brane with electro-
lyte while shaking
it gently. Refill
with clean electro-
lyte.
5 Gently tap the sides of the membrane cap
with your finger tip to ensure that no air
bubbles remain trapped. To avoid damag-
ing to the membrane, do not tap the mem-
brane directly on the bottom.
6 With the sensor facing down, screw the
cap clockwise. Some electrolyte will over-
flow.
When not in use, protect the mem-
brane by placing the protective cap
on it.
Range 0.00 to 45.00 mg/L O2
0.0 to 300 %O2
0.0 to 50.0 °C
Resolution 0.01mg/L O2
0.1 %O2
0.1°C
Accuracy ±1.5% Full Scale mg/L O2
(@25°C/77°F) ±1.5% Full Scale %O2
±0.5°C
TypicalEMC ±0.3 mg/L O2 / ±3.5 %O2
Deviation ±0.5°C
Calibration Automatic in saturated air
Temperature Automatic from 0 to 50°C
Compensation (32to 122°F)
Altitude 0 to 4 km
Compensation 100mresolution
Salinity 0 to 80 g/L
Compensation 1g/Lresolution
Environment 0 to 50°C (32 to 122°F)
RH100%
Power supply • 4x1.5V AA batteries;
200hoursof continuoususe;
auto-offafter4hours.
• 12 Vdc adapter
Dimensions 196 x 80 x 60 mm
(7.7 x 3.1 x 2.4")
Weight 500 g (1.1 lb.)
SPECIFICATIONS
Shipping
cap
black
red
THEN SCREW
BACK ON
THIRD
TAP
SECOND
FILL
FIRST
INSERT
O’RING

89
• For an accurate calibration, it is recom-
mended to wait an additional 5 or 10 min-
utesto ensure optimumconditioningof the
probe.
• Removetheprotectivecap.
• Press CAL. "----" appears
onthelargerLCDtogether
with "CAL" to indicate that
theinstrumentisincalibra-
tionmode.
• The instrument will auto-
maticallystandardizeitself
to the actual saturation
value. After approx. 1
minute it will show "100%"
on the LCD and a small
"SAMPLE" to indicate that
the calibration is complete.
• Press FACTOR and ensure F1 and F2 are
set to the appropriate altitude and salinity
values(pages10-11).
Notes: • Theinstrumentmustbecalibrated
whenever the probe, membrane
or the electrolyte is changed.
• To exit the calibration mode during
calibration,pressCAL.
• The display may be
switchedfromreadings
in%saturationto mg/
Lwithoutrecalibration,
by simply pressing
RANGE.
CALIBRATION
PROBE POLARIZATION
The probe is under polarization with a fixed
voltage of approximately 800 mV.
Probepolarization isessential forstable mea-
surements with the same recurring degree of
accuracy.
With the probe properly polarized, oxygen is
continually "consumed" by passing through
the sensitive diaphragm and dissolving in the
electrolytesolutioncontainedinsidetheprobe.
If this operation is interrupted, the electrolyte
solution continues to be enriched with oxygen
until it reaches an equilibrium with the sur-
rounding solution. Whenever measurements
are taken with a non-polarized probe, the
oxygen level indicated is that of the test solu-
tion as well as any oxygen present in the
electrolyte solution. This reading is obviously
incorrect. The Hanna oxygen meter shown
here automatically polarize the probe when
they are switched on.
Calibration is simple and is recommended
every time the meter is switched on.
• Makesure the probeis readyfor measure-
ment (see page 5), i.e. the membrane is
filled with electrolyte and probe is con-
nectedtothemeterandproperlypolarized.
• Switch the meter on.
• "COND" appears on the
display to inform you that
theprobeisinauto-condi-
tioning(automaticpolariza-
tion) mode.
• Once "COND"disappears
the probe is polarized and
instrument can be calibrated.
ON/OFF
CAL
CAL
SAMPLE
%
°C
CAL
RANGE

10 11
If the sample contains significant salinity or
if the measurement is taken at a higher
altitude than sea level, the read-out values
mustbecorrected(bytakingintoaccountthe
lower degree of oxygen solubility in such
conditions- see below).
Set the altitude and/or the salinity before
calibration and taking mg/L measurements.
Themeterwillautomaticallycompensatefor
thesefactors.
%O2SATURATION READINGS
The%O2readingprovidestherateofoxygen
saturation with reference to 100.0% at sea
level.
TEMPERATURE READINGS
The lower part of the display
will show the measured
temperature in Celsius
degrees.
Allow the probe to reach thermal equilibrium
with the sample before taking any measure-
ment. The greater the difference between the
ambienttemperatureandthetemperatureofthe
sample, the longer it will take the probe to
acclimatized itself to the sample.
MEASUREMENT
Makesurethemeterhasbeen
calibrated and the protective
cap has been removed. Im-
merse the tip of the probe in
the sample to be tested and
ensure that the temperature
sensor is also immersed.
To display values in % satura-
tion, press RANGE.
Foraccuratedissolvedoxygenmeasurements,
a water movement of at least 30 cm (12”)/sec
is required. This is to ensure that oxygen
depleted on the membrane surface is con-
stantly replenished. A moving stream will pro-
vide adequate circulation.
Duringfieldmeasurements,thisconditionmay
be obtained by manually stirring the probe.
Accurate readings are not possible while the
liquid is stationary.
Duringlaboratorymeasurements,theuseof a
magneticstirrertoensureacertainagitationof
thefluidisrecommended.Thisway,anyerrors
due to the presence of air bubbles on the
membranesurfaceareminimized.
Foranaccuratemeasurement,allowsufficient
timeforthermalequilibrium betweentheprobe
and the measurement sample (a few minutes
if the temperature difference is several de-
grees).
mg/L READINGS
Themg/Lreadingsmakeitpossibletoreadthe
concentrationof thedissolved oxygen directly
in ppm.
RANGE
SAMPLE
%
°C

12 13
ALTITUDE COMPENSATION
Press FACTOR and “F1” will
bedisplayed.
Use the UP and the DOWN
keystosetthealtitudefrom0
and4.0km(4000m),insteps
of 0.1 km (100 m).
Thetableprovidesanideaoftheerrorthatcan
be introduced at different altitudes and the
quantitytobesubtractedtocorrectthereading.
FACTOR
SAMPLE
ppm
F1
or
FACTOR
or
SAMPLE
F2
ppm
35 g/L
9.0
8.6
8.3
8.0
7.6
7.4
7.1
6.9
6.6
6.4
30 g/L
9.3
8.9
8.6
8.2
7.9
7.6
7.3
7.1
6.8
6.6
°C
10
12
14
16
18
20
22
24
26
28
0 g/L
11.3
10.8
10.3
9.9
9.5
9.1
8.7
8.4
8.1
7.8
10 g/L
10.6
10.1
9.7
9.3
8.9
8.5
8.2
7.9
7.6
7.4
20 g/L
9.9
9.5
9.1
8.7
8.4
8.0
7.8
7.5
7.2
7.0
Salinity(g/L)atSeaLevel °F
50.0
53.6
57.2
60.8
64.4
68.0
71.6
75.2
78.8
82.4
°C
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
42
44
46
48
50
0
14.6
13.8
13.1
12.4
11.8
11.3
10.8
10.3
9.9
9.5
9.1
8.7
8.4
8.1
7.8
7.5
7.3
7.1
6.8
6.6
6.4
6.3
6.1
5.9
5.8
5.6
300
14.1
13.3
12.7
12.0
11.4
10.9
10.4
9.9
9.7
9.2
8.8
8.4
8.1
7.8
7.5
7.2
7.1
6.9
6.6
6.4
6.2
6.1
5.9
5.7
5.6
5.4
600
13.6
12.9
12.2
11.6
11.0
10.5
10.1
9.6
9.2
8.7
8.5
8.1
7.8
7.5
7.3
7.0
6.8
6.6
6.3
6.2
6.0
5.8
5.7
5.5
5.4
5.2
1200
12.7
12.0
11.4
10.8
10.3
9.8
9.4
9.0
8.6
8.3
7.9
7.7
7.3
7.0
6.8
6.5
6.4
6.2
5.9
5.7
5.6
5.4
5.3
5.1
5.0
4.9
1500
12.3
11.6
11.0
10.4
9.9
9.5
9.1
8.7
8.3
8.0
7.7
7.3
7.1
6.8
6.6
6.3
6.1
6.0
5.7
5.6
5.4
5.2
5.1
4.9
4.8
4.7
1800
11.8
11.2
10.6
10.1
9.6
9.2
8.8
8.3
8.0
7.7
7.4
7.1
6.8
6.6
6.3
6.1
5.9
5.8
5.5
5.4
5.2
5.0
4.9
4.8
4.6
4.5
900
13.2
12.4
11.9
11.2
10.6
10.2
9.7
9.3
8.9
8.6
8.2
7.8
7.5
7.3
7.0
6.8
6.6
6.4
6.1
5.9
5.8
5.6
5.5
5.3
5.2
5.0
Altitude above Sea Level (in meters)
2100
10.9
10.3
9.8
9.3
8.9
8.5
8.1
7.8
7.5
7.2
6.9
6.6
6.3
6.1
5.9
5.7
5.5
5.4
5.2
5.0
4.8
4.7
4.6
4.4
4.3
4.2
2400
10.2
9.6
9.1
8.6
8.2
7.8
7.5
7.2
6.9
6.6
6.3
6.0
5.8
5.7
5.4
5.2
5.1
4.9
4.8
4.6
4.5
4.3
4.3
4.1
4.0
3.9
2700
9.4
8.9
8.5
8.0
7.6
7.3
7.0
6.6
6.4
6.1
5.9
5.6
5.5
5.2
5.0
4.9
4.7
4.6
4.5
4.3
4.2
4.0
4.0
3.8
3.7
3.6
3000
8.7
8.2
7.8
7.4
7.1
6.8
6.4
6.2
5.9
5.7
5.5
5.3
5.1
4.8
4.7
4.6
4.4
4.2
4.1
4.0
3.9
3.7
3.7
3.5
3.5
3.4
3300
8.1
7.7
7.3
6.9
6.5
6.3
6.0
5.7
5.5
5.3
5.1
4.9
4.7
4.5
4.3
4.2
4.1
3.9
3.8
3.7
3.6
3.5
3.4
3.3
3.2
3.1
3600
7.6
7.1
6.7
6.4
6.1
5.8
5.6
5.3
5.1
4.9
4.7
4.5
4.4
4.2
4.0
3.9
3.8
3.7
3.5
3.5
3.3
3.2
3.1
3.1
2.9
2.9
4000
6.6
6.3
6.0
5.7
5.4
5.1
4.9
4.7
4.5
4.3
4.1
4.0
3.8
3.7
3.6
3.5
3.3
3.2
3.1
3.0
2.9
2.9
2.8
2.7
2.6
2.6
SALINITYCOMPENSATION
Press FACTOR twice and
“F2”will bedisplayed.
Press UP and DOWN to set
thesalinity between0 and 80
g/L.
Press FACTOR again to dis-
playthetemperature.

14 15
• Make sure that the rubber O-ring is seated
properly inside the membrane cap.
• With the sensor facing down, screw the
membrane cap clockwise. Some electro-
lyte will overflow.
ThePlatinum cathode sensor (#8 inthe Func-
tionalDescriptiononpage2)shouldalwaysbe
bright and untarnished. If it is tarnished or
stained, which could be due to contact with
certain gases or extended use with a loose or
damaged membrane, the cathode sensor
shouldbecleaned.Useaclean,lint-freecard-
board or cloth. Rub the cathode very gently
side to side 4-5 times. This will be enough to
polish and remove any stains without damag-
ingtheplatinumtip.Then,rinse the probe with
deionizedordistilledwater.Installanewmem-
brane and fill it with fresh electrolyte following
the instructions above. Recalibrate the instru-
ment.
Important: In order to have accurate and
stable measurements, it is important that the
surface of the membrane is in perfect condi-
tion. This permeable membrane isolates the
sensor elements from the environment but
allowsoxygen toenter. Ifanydirtis deposited
on the membrane, rinse it carefully with dis-
tilled or deionized water. If any imperfections
areobserved, orany damage is evident (such
as wrinkles, tears or holes), the membrane
shouldbereplaced.MakesurethattheO-Ring
is properly seated in the membrane cap.
PROBE & MEMBRANE MAINTENANCE
The oxygen probe body is made of reinforced
polypropylene for maximum durability.
Athermistor sensor measurestemperature of
thesample.Itisrecommendedthattheprotec-
tivecapbealwayskeptontheprobe when the
probe is not in use.
To replace the membrane or refill it with
electrolyte, proceed as follows:
• Removethe protective capby gently twist-
ing and pulling it off the
probe (see fig. 1).
• Unscrew the membrane
byturningitcounterclock-
wise (see fig.2)
• Wet the sensor by soak-
ing the bottom 2½ cm
(1") of the probe in elec-
trolyte (HI 7041S) for 5
minutes.
• Rinse a new membrane
(HI 76407A) with elec-
trolyte while shaking it
gently. Refill with clean
electrolyte.
• Gently tap the sides of
themembranewithyour
finger tip to ensure that
no air bubbles remain
trapped. Do not directly
tap the bottom as this
may cause irreparable
damage to the mem-
brane.
TWIST
AND
PULL
fig. 1
UNSCREW
fig. 2

16 17
BATTERY REPLACEMENT
When the batteries are run
down "LOBAT" is displayed
on the Liquid Crystal Dis-
play.
This is to inform the user that the display will
be shut-off after about 4 hours of use to
prevent erroneous measurements due to low
voltage.
Battery replacement must only take place in a
non-hazardous area using alkaline batteries.
In order to replace run down batteries, simply
remove the two screws
on the rear cover of the
instrument (#1 in the
FunctionalDescriptionon
page 3) and replace the
four 1.5V AA batteries
withnewones,payingat-
tention to the correct po-
larity.
A 12 Vdc power source
canalsobeusedtopower
theunit(seeaccessories).
Simply unscrew the pro-
tective cap on the top of
theinstrument(#10 page
3)andplugthepowersup-
ply into the socket.
Note: The instrument uses the following con-
figuration.
UseonlytheHannavoltageadapters(suchas
HI 710005 or HI 710006 - see below) with
proper polarity configuration.
Themetercanhoweveralsorunonotheradapt-
ers. In this case, check the correct polarity of
youradapterbeforeconnectingittothemeter.
ACCESSORIES
HI7041S Electrolyte solution for D.O.
probe,30mL
HI76407/4F D.O.probewith4m(13’)cable
andprotectivesleeve
HI76407/10F D.O. probe with 10 m (33’)
cableandprotectivesleeve
HI76407A/P D.O.membrane(5pcs)
HI710005 115 Vac to 12 Vdc power
adapter,USplug
HI710006 230 Vac to 12 Vdc power
adapter,Europeanplug
LOBAT
SAMPLE
°C
ppm
+-

18 19
CE DECLARATION OF CONFORMITY
Recommendations for Users
Before using these products, make sure that they are entirely suitable for the environment
in which they are used.
Operation of this instrument in residential area could cause unacceptable interference to
radio and TV equipment, requiring the operator to take all necessary steps to correct
interferences.
Anyvariationintroducedbytheusertothesuppliedequipmentmaydegradetheinstrument's
EMC performance.
To avoid electrical shock, do not use these instruments when voltage at the measurement
surface exceeds 24VAC or 60VDC.
To avoid damage or burns, do not perform any measurement in microwave ovens.
WARRANTY
All Hanna meters are warranted for two
years against defects in workmanship and
materials when used for their intended purpose
and maintained according to the instructions.
Probes are warranted for six months.
This warranty is limited to repair or replacement
free of charge.
Damages due to accidents, misuse, tampering
or lack of prescribed maintenance are not cov-
ered.
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 war-
ranty, you will be notified of the charge for repair
or replacement. If the instrument is to be re-
turned to Hanna Instruments, please obtain a
Return Goods Authorization from the Customer
Service Department and then send it with ship-
ment cost prepaid.
When shipping any instrument, make sure it is
properly packaged for complete protection.
HannaInstrumentsreservestherighttomodifydesign,con-
structionandappearanceofitsproductswithoutadvancenotice.