Hanna Instruments HI 9142 User manual

Instruction Manual
HI 9142
Portable Waterproof
Dissolved Oxygen Meter
This instrument is in Compliance with the CE Directives
http://www.hannainst.com

PRELIMINARY EXAMINATION
Removetheinstrumentfromthepackingmaterial
andexamineittomakesurethatnodamagehas
occurred during shipping. If there is any
damage, notify your Dealer.
In addition to this manual you should find the
followingitems:
•D.O.meter
•4 x 1.5V AA batteries
•DO Probe (HI 76407/4)
•Membrane cap (HI 76407A)
•Protectivecap
•30 mL electrolyte solution (HI 7041S)
•Rugged carrying case
Note: Save all packing material until you are
sure that the instrument functions
correctly. All defective items must be
returned to us in the original packaging
with the supplied accessories.
GENERAL DESCRIPTION
Hanna Instruments' HI 9142 is a water-resis-
tant, Dissolved Oxygen meter with Automatic
TemperatureCompensation.Ithasbeendevel-
oped for dissolved oxygen measurement in
water and wastewater applications as well as
otherapplicationssuchasfishfarming.
Dissolvedoxygenisindicatedintenthsofparts
per million (ppm=mg/l) .
Four1.5VAAbatteriesprovidepowerandmake
theinstrumentcompletelyportable.
Themeterishousedinaruggedwater-resistant
caseformaximumprotectioninthefieldaswell
as in the laboratory.
Thedissolved oxygenprobehas amembrane
coveringthepolarographicsensorsandabuilt-
1
DearCustomer,
Thank you for choosing a Hanna Instruments
Product.
Please read this instruction manual carefully
beforeusingthe instrument.
Thismanualwillprovideyouwithalltheneces-
sary information for the correct use of the
instrument, as well as a precise idea of its
versatility in a wide range of applications.
Thisinstrumentisincompliancewith direc-
tivesEN50081-1and50082-1.
TABLE OF CONTENTS
PreliminaryExamination ............................. 1
GeneralDescription..................................... 1
FunctionalDescriptionProbe ...................... 2
FunctionalDescriptionMeter....................... 3
Specifications ............................................. 4
InitialProbePreparation .............................. 5
CalibrationProcedure .................................. 6
TakingMeasurements ................................. 8
AltitudeandSalinityCompensation............. 9
Probe&MembraneMaintenance .............. 11
BatteryReplacement ................................ 13
Accessories .............................................. 14
Warranty ................................................... 15
OtherProductsfromHanna....................... 16
CEDeclarationofConformity .................... 17
ISO 9000 Certified
Companysince1992

FUNCTIONAL DESCRIPTION
1. BatteryCompartment
2. ProbeConnector
3. LiquidCrystalDisplay
4. ON/OFFButton
5. CalibrationButton
6. SlopeCalibrationTrimmer
7. ZeroD.O. CalibrationTrimmer
3
in thermistor for temperature measurements
and compensation. The thin permeable
membrane isolates the sensor elements from
thetestingsolution,butallowsoxygentoenter.
When a voltage is applied across the sensor,
oxygenthathaspassedthroughthemembrane
reacts causing current to flow, allowing the
determinationofoxygen.
1. D.O.Probe
2. ProtectiveCap
3. Water-tightShieldedCable
4. Polypropylene Probe Body
5. TemperatureSensor
6. O-RingSeal
7. SilverChlorideAnode
8. PlatinumCathode(sensor)
9.OxygenPermeablePTFEMembrane
10.MembraneCap
FUNCTIONAL DESCRIPTION PROBE
9
1
3
4
4
5
6
7
8
9
2
10
8
7
6
2

INITIAL PROBE PREPARATION
Probe Preparation
All probes shipped from Hanna Instrument
are dry. 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. This cap is for ship-
ping purposes and can be
thrown away.
2 Wet the sensor by soaking the
bottom 2½ cm (1") of the probe
in electrolyte (HI 7041S) for 5
minutes.
3 Rinse the membrane (HI 76407A supplied
in the kit with the
meter) with elec-
trolyte while
shaking it gen-
tly. Refill with
clean electrolyte.
4 Gently tap the
sides of the
membrane with
your finger tip
to ensure that
no air bubbles
remain trapped.
To avoid dam-
aging the mem-
brane, do not tap the membrane directly on
the bottom.
5 Place rubber O-Ring properly inside the
membrane cap.
6 With the sensor facing down, screw the
cap clockwise. Some electrolyte
will overflow.
When not in use and during polar-
ization, place the protective cap
supplied in the kit with the meter.
S
hipping
cap
black
red
THEN SCREW
BACK ON
THEN TAP
FILL FIRST
5
HI9142
Range 0.0 to 19.9 mg/l
Resolution 0.1 mg/l
Accuracy ±1.5% Full Scale
TypicalEMC ±0.8 mg/l
Deviation with 4 m cable probe
Calibration Manual on 2 points
(zeroandslope)
Temperature Automatic from 0 to 30°C
Compensation (32to86°F)
Probe HI76407/4polarographic
with 4 m cable
Battery Type 4 x 1.5V AA
Life 500hoursofcontinuoususe
Environment 0 to 50°C (32 to 122°F);
100%RH
Dimensions 196x80x60 mm (7.7x3.1x2.4")
Weight 425 g (15 oz.); kit: 1.4 kg (3.1 lbs)
SPECIFICATIONS
4

Zero Calibration:
•DiptheprobeintoHI7040zero
oxygensolutionandstirgen-
tly for 2-3 minutes.
•Allow 2 minutes for the LCD readout to
stabilize.
•Adjust the zero D.O. calibration
trimmer until the display reads
"0.0".
Note Thezerocalibrationscrewis
located close to the probe
connector.
Slope Calibration:
Itissuggestedtoperformtheslopecalibration
insaturedair.
•Rinse the probe in a large amount of clean
water to remove any residual zero oxygen
solution.
•Dry the probe tip and allow a few minutes for
theLCDreadouttostabilize.
•Press and hold the CAL key.
•Adjust the slope trimmer on
the top of the meter to read
"100%" on the LCD (while still
holdingtheCALbutton).
NoteTheslopecalibrationscrew
islocatedfarthestfromtheprobe
connection.
•Release the CAL key and the
LCD will display the value in
ppmof oxygen.
The zero calibration of the HI 9142 is very
stable, therefore this procedure needs only to
be performed whenever the probe is re-
placed.
However, because the slope calibration is
more critical, it is recommended to perform
this procedure every week.
%
CAL
7
CALIBRATION PROCEDURE
PROBE POLARIZATION
The probe is under polarization with a fixed
voltageofapproximately800mV.
Probepolarizationis essential for stable mea-
surements with the same recurring degree of
accuracy.
With the probe properly polarized, oxygen is
continually"consumed"bypassingthroughthe
sensitivediaphragmanddissolvingintheelec-
trolyte solution contained in the probe.
If this operation is interrupted, the electrolyte
solution continues to be enriched with oxygen
untilitreachesanequilibriumwiththesurround-
ingsolution.
Whenevermeasurementsaretakenwithanon-
polarized probe, the oxygen level revealed is
both that of the tested solution as well as that
presentintheelectrolytesolution.Thisreading
is incorrect
Thecalibrationis very simple and fast.
•Make sure the probe is ready for measure-
ments(see initialpreparation atpage7), i.e.
themembraneisfilledwithelectrolyteandthe
probe is connected to the meter.
•Switchthemeteronbypress-
ing the ON/OFF key
•Foranaccuratecalibration,itisrecommended
that you wait at least 15 minutes to ensure
preciseconditioningoftheprobe.
•Remove the protective cap
fromtheD.O.probe.
ON/OFF
6

ALTITUDE & SALINITY COMPENSATION
If the sample contains salts or if you are
performing the measurements at a different
altitudethansealevel,thereadoutvaluesmust
be corrected, taking into account the lower
degreeofoxygensolubility.
ALTITUDE COMPENSATION
Allthe readoutsarereferred atsea level,thus
the displayed measurements are higher than
theactual values.Infact, altitude affectsD.O.
concentrationdecreasingitsvalue.Thefollow-
ingtablereportstheoxygensolubilityatvarious
temperaturesandaltitudes,basedonsealevel
barometricpressureof760 mmHg.
°C
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
0 m
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
300 m
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
600 m
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
1200 m
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
1500m
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
1800m
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
900 m
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
Altitude, Meters above Sea Level
This gives an idea of the error that can be
introducedatdifferentaltitudesandallowsyou
to calculate the quantity to be subtracted to
correctyourreading.
°F
32.0
35.6
39.2
42.8
46.4
50.0
53.6
57.2
60.8
64.4
68.0
71.6
75.2
78.8
82.4
86.0
89.6
93.2
96.8
100.4
104.4
9
TAKING MEASUREMENTS
Makesurethemeterhasbeen
calibrated and the protective
cap has been removed. Im-
mersethetipoftheprobeinthe
sampletobetested.
Make sure the temperature sensor is also
immersed.
Foraccuratedissolvedoxygenmeasurements
awatermovementof0.3m/secisrequiredata
minimum. This is to ensure that the oxygen-
depleted membrane surface is constantly re-
plenished. A moving stream will provide ad-
equatecirculation.Toquicklycheckifthewater
speed is sufficient, wait for the reading to
stabilize and then move the D.O. probe. If the
readingisstillstable,themeasurementcondi-
tionsareright,whileifthereadingincreasesthe
watermovementisnotadequate.
Duringfieldmeasurements,thisconditionmay
bemet bymanuallyagitating theprobe.Accu-
ratereadingsarenotpossiblewhiletheliquidis
at rest.
Duringlaboratorymeasurements,theuseof a
magnetic stirrer to ensure a certain velocity in
the fluid is recommended. In this way, errors
duetothediffusionoftheoxygenpresentinthe
air in the solution are reduced to a minimum.
Atalltimes,timenecessaryforthermalequilib-
riumtooccurbetweentheprobeandthesample
mustbeallowed(afewminutesfortemperature
differenceofseveraldegrees).
8

PROBE & MEMBRANE MAINTENANCE
The oxygen probe body is made of reinforced
plasticfor maximumdurability.
Athermistortemperaturesensorprovidestem-
peraturemeasurementsofthesampletested.It
isalwaysrecommendedthattheprotectivecap
bekeptontheprobewhentheprobeisnotinuse
toprovideprotectionagainstdamageanddirt.
Toreplacethemembraneorrefillwithelectro-
lyte, proceed as follows:
•Removetheprotectivecap
bygentlytwistingandpull-
ing it off the body of the
probe (see fig. 1).
•Unscrew the membrane
by turning it counter-
clock-wise with the other
hand (see fig. 2)
•Wet the sensor by soak-
ingthebottom2½cm(1")
oftheprobeinelectrolyte
(HI7041S)for5minutes.
•Rinsethenewmembrane
(HI76407A)suppliedwith
themeterwithelectrolyte
while shaking it gently.
Refill with clean electro-
lyte.
•Gentlytapthesidesofthe
membrane with your fin-
ger tip to ensure that no
air bubbles remain
trapped. Do no directly
tap the bottom with your
fingerasthiswilldamage
themembrane.
TWIST
AND
PULL
fig. 1
UNSCREW
fig. 2
11
SALINITY COMPENSATION
The table below shows the influence of salt in
themeasurementofoxygen.
In HI 9142 allthereadoutsarereferredto0g/l
of salinity value. In fact, salinity affects D.O.
concentrationdecreasingits value.
Foryourreferencethetable belowreportsthe
oxygensolubilityatvarioustemperaturesand
salinity. From the table you can calculate the
quantitytobesubtractedtocorrectyourread-
ing.
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
°F
50.0
53.6
57.2
60.8
64.4
68.0
71.6
75.2
78.8
82.4
Salinity (g/l) at Sea Level
10

BATTERY REPLACEMENT
Whenthebatteryisrundown
"V"isdisplayedontheLiquid
Crystal Display to warn the
user.
Thisistoinformtheuserthatthedisplaywillbe
shut-off after about 4 hours of use to prevent
erroneous measurements being taken due to
lowvoltage.
Battery replacement must only take place in a
non hazardous area using alkaline 1.5 V AA
type batteries.
In order to replace run-down batteries, simply
removethetwoscrewsontherearcoverofthe
instrumentandreplacethefour1.5VAAbatter-
ies with new ones, paying attention to the
correct polarity (refer to #1 in the Functional
Description page 5).
V
13
•Make sure that the rubber O-ring is seated
properly inside the membrane cap.
•With the sensor facing down, screw the
membrane cap clock-wise. Some electro-
lytewilloverflow.
The Platinum cathode (#8 in the Functional
Descriptionatpage4)shouldalwaysbebright
and untarnished. If it is tarnished or stained,
which could be due to contact with certain
gasesorextendedusewithalooseordamaged
membrane,thecathodeshouldbecleaned.You
canuseacleanlint-freecardboardorcloth.Rub
thecathodeverygentlysideto side 4-5 times.
This will be enough to polish and remove any
stainswithoutdamagingtheplatinumtip.After-
wards,rinsetheprobewithdeionizedordistilled
water and install a new membrane cap using
fresh electrolyte and follow the steps above.
Recalibratetheinstrument.
Important:inordertohaveaccurateandstable
measurements,itisimportantthatthe surface
of the membrane is in perfect condition. This
semi-permeablemembraneisolatesthesensor
elementsfromtheenvironmentbutallowsoxy-
gen to enter. If any dirt is observed on the
membrane,rinsecarefullywithdistilledordeion-
izedwater.Ifanyimperfectionsstillexist,orany
damageisevident(suchaswrinklesortears-
holes), the membrane should be replaced.
MakesurethattheO-Ringisproperlyseatedin
themembrane cap.
12

WARRANTY
AllHannaInstrumentsmetersare warranted
fortwoyearsagainstdefectsinworkmanship
and materials when used for their intended
purpose and maintained according to the in-
structions. The probes are warranted for a
period of six months.
Damagesduetoaccidents,misuse,tampering
or lack of prescribed maintenance are not
covered. This warranty is limited to repair or
replacement free of charge.
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 charge for
repairorreplacement.Iftheinstrumentistobe
returnedtoHannaInstruments,obtainaReturn
Goods Authorization from the Customer Ser-
vice Department first and then send it with
shipment cost prepaid. When shipping any
instrument, make sure it is properly packaged
forcompleteprotection.
Tovalidateyourwarranty,filloutandreturnthe
enclosedwarrantycardwithin14daysfromthe
date of purchase.
All rights are reserved. Reproduction in whole
or in part is prohibited without the written
consent of the copyright owner.
HannaInstrumentsreservestherighttomodify
thedesign,constructionandappearanceofits
productswithoutadvancenotice.
15
ACCESSORIES
HI7040M ZeroOxygencalibrationso-
lution,230 mL
HI7040L ZeroOxygen calibrationso-
lution,460 mL
HI7041S RefillingElectrolytesolution,
30 mL
HI721308 1.5VAAsizealkalinebattery
(10pcs)
HI76407/10 Spare probe with 10 meters
(33') cable
HI76407/20 Spare probe with 20 meters
(66') cable
HI76407A/P Sparemembrane(5pcs)
MAN9142R1 Instructionmanual
14

CE DECLARATION OF CONFORMITY
RecommendationsforUsers
Before using this product, make sure that it is entirely suitable for the environment
in which it is used.
Operation of this instrument in residential area could cause unacceptable interfer-
ences 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
instrument's EMC performance.
To avoid electrical shock, do not use this instrument when voltages at the measure-
ment surface exceed 24VAC or 60 VDC.
To avoid damages or burns, do not perform any measurement in microwave ovens.
In particular cases the meter could turn off. In these cases it can be turned on by
pressing the ON/OFF key.
17
•CALIBRATION AND MAINTENANCE
SOLUTIONS
•CHEMICAL TEST KITS
•CHLORINE METERS
•CONDUCTIVITY/TDS METERS
•DISSOLVED OXYGEN METERS
•HYGROMETERS
•ION SPECIFIC METERS (Colorimeters)
•MAGNETIC STIRRERS
•pH/Na/NaCl METERS
•pH/ORP/Na ELECTRODES
•PROBES (DO, µS/cm, RH, T, TDS)
•PUMPS
•REAGENTS
•SOFTWARE
•THERMOMETERS
•TITRATORS
•TRANSMITTERS
•TURBIDITY METERS
•Wide Range of Accessories
Most Hanna meters are available in the fol-
lowing formats:
•BENCH-TOP METERS
•POCKET-SIZED METERS
•PORTABLE METERS
•PRINTING/LOGGING METERS
•PROCESS METERS (Panel and Wall-
mounted)
•WATERPROOF METERS
•METERS FOR FOOD INDUSTRY
For additional information, contact your dealer
or the nearest Hanna Customer Service Cen-
ter. You can also e-mail us at:
[email protected].
OTHER PRODUCTS FROM HANNA
16

MAN9142R1
12/95
PRINTED IN
PORTUGAL
http://www.hannainst.com