LaMotte 1200 User manual

5.00 • RM626728

TABLE OF CONTENTS
GENERAL INFORMATION
Packaging and Delivery ..........................4
General Precautions ...........................4
Safety Precautions ............................4
Limits of Liability .............................4
Specifications ...............................5
Parts & Accessories ............................6
EPA Compliance .............................7
Warranty .................................7
CE Statement...............................7
CHEMICAL TESTING
Water Sampling for Chemical Analysis ................8-9
Filtration .................................9
An Introduction To Colorimetric Analysis..............10-11
Reagent Blank..............................11
Colorimeter Tubes ............................11
Sample Dilution Techniques & Volumetric Measurement........12
Interferences...............................13
Stray Light Interference .........................13
GENERAL OPERATING INFORMATION
Overview...............................14-15
The Keypad and Display.........................16
Testing Tips ...............................17
CALIBRATION PROCEDURE ................18-19
ANALYSIS PROCEDURE ..................20-21
AVAILABLE TEST KITS .....................22
TROUBLESHOOTING GUIDE .................23
RS232 PORT..........................24
MAINTENANCE OF THE 1200
.....................................25
Replacing the Battery ..........................25
Repairs..................................25
3

GENERAL INFORMATION
PACKAGING & DELIVERY
Experienced packaging personnel at LaMotte Company assure adequate
protectionagainst normal hazardsencountered in transportation of shipments.
Afterthe product leaves themanufacturer, all responsibility forsafe delivery is
assured by the transportation company. Damage claims must be filed immediately
withthe transportation companyto receive compensationfor damaged goods.
Shouldit be necessaryto returnthe instrument forrepair or servicing, pack the
instrumentcarefully in a suitable container with adequatepacking material. A
returnauthorization number must beobtained from LaMotte Companyby calling
1-800-344-3100 or faxing 1-410-778-6394. Attach a letter with the authorization
number to the shipping carton which describes the reason for the return. This
informationwill enablethe servicedepartment tomake therequired repairsmore
efficiently.
GENERAL PRECAUTIONS
Readthe instruction manualbefore attempting toset upor operate this
instrument. Failure to do so could result in personal injury or damage to the
instrument.
The 1200 Colorimeter should not be stored or used in a
wet or corrosive environment. Care should be taken to
prevent water from wet colorimeter tubes from entering
the colorimeter light chamber.
NEVERPUT WET TUBESIN THE COLORIMETER.
SAFETY PRECAUTIONS
Readthe label on all reagent containers. Somelabels include precautionary
noticesand first aidinformation. Certain reagentsare considered hazardous
substancesand are designatedwith a *in the instructionmanual. Material Safety
DataSheets (MSDS) aresupplied forthese reagents. Readaccompanying MSDS
beforeusing these reagents.Additional emergency informationfor all LaMotte
reagentsis available24 hours aday fromthe PoisonControl Center listedin the
frontof the phonebook. Be preparedto supply the name andfour digit LaMotte
code number found on the container label or at the top of the MSDS. LaMotte
reagentsare registered withPOISONDEX, a computerized poison control
informationsystem availableto alllocal poisoncontrol centers.
LIMITS OF LIABILITY
Underno circumstances shall LaMotteCompany be liable forloss of life,
property,profits, orother damagesincurred throughthe useor misuseof their
products.
4

SPECIFICATIONS
Instrument Type Single wavelength, direct reading colorimeter
Measurement Wavelengths: 420 nm, 460 nm, 510 nm, 530 nm, 570 nm or
605 nm
Readable Resolution: Determined by test factor
Photometric Precision: ±0.001 Absorbance Unit
Range: 0 - 2.00 absorbance units
Display: 3 ½ digits
Response Time: 2 seconds
Warm-up Time: Not required
Lamp: LED
Detector: Silicon Photodiode
Sample: 10 mL in capped tube
Sample Chamber: Accepts 25mm diameter flat-bottomed tubes
(capped)
Power Source: Battery Operation: 9 Volt Alkaline
Line Operation: 120V/60Hz, 220V/50Hz, with available adapter
Size (L X W X H): 8.5 x 16.2 x 6.7 cm, 3.4 X 6.4 X 2.6 inches
Shipping Weight: 11 oz (312 g) meter only
Serial Interface: RS232, 8 pin mDIN, 9600b, 8, 1, n
5

PARTS & ACCESSORIES
Included in the Model 1200 Colorimeter Kit :
1200 Colorimeter
Colorimeter tubes, set of 6
Water Sample Collecting Bottle
Reagent System
Optional Accessories
AC Adapter, 110V/60Hz Code 1773
AC Adapter, 220V/50Hz Code 1774
Colorimeter Tubes, set of 6 Code 0290-6
6

EPA COMPLIANCE
The 1200 Chlorine Colorimeter is an EPA Accepted instrument.
EPA Accepted means that the instrument meets
requirements for colorimeters as found in test procedures
that are approved for the National Primary Drinking
Water Regulations (NPDWR) or National Pollutant
DischargeEliminationSystems (NPDES) compliance
monitoringprograms. EPA Acceptedinstruments may be
used with approved test procedures without additional
approval.
WARRANTY
This instrument is guaranteed to be free from defects
in material and workmanship for one year from
original purchase date. If within that time the
instrument is found to be defective, it will be repaired
withoutcharge exceptfor transportation costs.The
guarantee does not cover batteries.
This guarantee is void under the following circumstances:
operatornegligence, improper application,and unauthorized servicing.
CE COMPLIANCE
The 1200 Colorimeter has
been independently tested
and has earned the
European CE Mark of
Compliance for
electromagnetic
compatibilityand safety.
7

CHEMICAL TESTING
WATER SAMPLING FOR CHEMICAL ANALYSIS
Taking Representative Samples
Theunderlying factor tobe consideredfor any typeof water sampling is whether
ornot the sample is truly representative ofthe source. To properly collect a
representative sample:
•Sample as frequently as possible.
•Collect a large sample or at least enough to conduct whatever tests are
necessary.
•Make a composite sample for the same sampling area.
•Handle the sample in such a way as to prevent deterioration or
contamination before the analysis is performed.
•Perform analysis for dissolved gases such as dissolved oxygen, carbon dioxide,
and hydrogen sulfide immediately at the site of sampling. These factors, as
well as samples for pH, cannot be stored for later examination.
•Make a list of conditions or observations which may affect the sample. Other
considerations for taking representative samples are dependent upon the
source of the sample. Taking samples from surface waters involves different
considerations than taking samples from impounded and sub-surface waters.
Sampling of Open Water Systems
Surfacewaters, such asthose foundinstreams andrivers, areusuallywell mixed.
Thesample should betaken downstream fromany tributary,industrial or sewage
pollutionsource. Forcomparison purposessamples may betaken upstreamand at
the source of the pollution before mixing.
Inponds, lakes, and reservoirs with restricted flow,it is necessaryto collect a
numberof samplesina crosssection ofthe bodyofwater, andwhere possible
composite samples should be made to ensure representative samples.
Tocollect samples fromsurface waters, selecta suitable plasticcontainer with a
tight fitting screw cap. Rinse the container several times with the sample to be
tested, then immerse the container below the surface until it is filled to
overflowingand replace the cap. If the sampleis not tobe tested immediately,
poura small part ofthe sample out andreseal. This will allowfor any expansion.
Anycondition which mightaffect the sampleshould be listed.
Sub-surfacesampling is requiredto obtain avertical profileof streams, lakes,
ponds, and reservoirs at specific depths. This type of sampling requires more
sophisticatedsampling equipment.
8

For dissolved oxygen studies, or for tests requiring small sample sizes, a Water
SampleBottle (LaMotteCode 1060)willserve asa subsurfaceor in-depth
sampler.This weighteddevice islowered tothe samplingdepth andallowed to
restat this depth for a few minutes.The water percolatesinto the sample
chamber displacing the air which bubbles to the surface. When the bubbles cease
torise, the devicehas flushed itselfapproximately five times and itmay be raised
tothe surface for examination.The inner chamberof the sampling deviceis lifted
outand portions of thewater sample are carefullydispensed for subsequent
chemical analysis.
ASnap-Plunger Water Sampler(LaMotte Code 1077)is another “in-depth”
samplingdevice which is designed to collect largesamples which canbe used for
amultitude of tests. Basically, this collection apparatusis a hollowcylinder with a
spring loaded plunger attached to each end. The device is cocked above the
surfaceof thewater andlowered to the desired depth.A weightedmessenger is
sentdown thecalibrated lineto trip the closing mechanismand theplungers seal
thesample from mixingwith intermediate layersas it is brought tothe surface. A
specialdrain outlet is providedto draw off samplesfor chemical analysis.
Sampling of Closed System
Toobtain representative samples fromconfined water systems, suchas pipe lines,
tanks, vats, filters, water softeners, evaporators and condensers, different
considerations are required because of chemical changes which occur between
theinlet andoutletwater. Onemust havea basicunderstandingof thetype of
chemicalchanges which occurfor thetype ofequipmentused. Also,
considerationshould begiven tothe rate of passage andretaining timefor the
process water.
Temperature changes play an important part in deciding exactly what test should
be performed. Process water should be allowed to come to room temperature,
20–25°C,beforeconducting any tests.
Whendrawing off samples from anoutlet pipe suchas atap, allow sampleto run
forseveral minutes, rinsingthe container severaltimes beforetaking the final
sample. Avoid splashing and introduction of any contaminating material.
FILTRATION
When testing natural waters that contain significant turbidity due to suspended
solids and algae, filtration is an option. Reagent systems, whether EPA, Standard
Methods,LaMotte orany others, will generally onlydetermine dissolved
constituents.Both EPA and Standard Methodssuggest filtration througha 0.45
micronfilter membrane, to removeturbidity, for thedetermination of dissolved
constituents.** To test for total constituents, organically bound and suspended or
colloidalmaterials, a rigoroushigh temperature aciddigestion is necessary.
**LaMotteoffers afiltering apparatus: SyringeAssembly (Code1050) and
Membrane Filters, 0.45 micron (Code 1103).
9

AN INTRODUCTION TO
COLORIMETRIC ANALYSIS
Mosttest substances in water are colorless andundetectable to thehuman eye. To
testfor their presencewe mustfind a wayto “see” them. The LaMotte
colorimetercan be usedto measure anytest substance that is itselfcolored or can
bereacted to producea color. Infact a simple definition ofcolorimetry is “the
measurementof color” and acolorimetric method is “anytechnique used to
evaluatean unknown colorin reference toknown colors”.In a colorimetric
chemicaltest, the intensityof the colorfrom the reaction must beproportional to
theconcentration of thesubstance beingtested. Some reactionshave limitations
orvariances inherent to themthat may give misleadingresults. Many such
interferencesare discussed witheach particular testinstruction. Inthe most basic
colorimetricmethod the reactedtest sample isvisually comparedto a known
color standard. However, accurate and reproducible results are limited by the
eyesight of the analyst, inconsistencies in the light sources, and the fading of
color standards.
Toavoid these sourcesof error, acolorimeter can beused to photoelectrically
measurethe amountof coloredlight absorbed by a coloredsample inreference to
acolorlesssample (blank).
Whitelight ismade upof many different colors orwavelengths oflight. A
colored sample typically absorbs only one color or one band of wavelengths from
thewhite light. Onlya small differencewould be measuredbetween white light
before it passes through a colored sample versus after it passes through a colored
sample.The reason for this is that theone color absorbedby the sampleis only a
smallportion of the totalamount of lightpassing through the sample.However, if
wecould select only that onecolor or bandof wavelengthsof light towhich the
testsample ismost sensitive,we would see a largedifference betweenthe light
beforeit passes throughthe sample andafter it passesthrough the sample.
A colorimeter passes a white light beam through an optical filter which transmits
only one particular color or band of wavelengths of light to the photodetector
whereit is measured. The differencein theamount of coloredlight transmitted
by a colorless sample (blank) and the amount of colored light transmitted by a
colored sample is a measurement of the amount of colored light absorbed by the
sample. In most colorimetric tests the amount of colored light absorbed is directly
proportional to the concentration of the test factor producing the color and the
pathlength through the sample. However,for sometests the amountof colored
lightabsorbed isinverselyproportional tothe concentration.
Thechoice of thecorrect optical filterand therefore thecorrect color or
wavelengthof light isimportant. It isinteresting to note that thefilter that gives
themost sensitive calibrationfor atest factor isthe complementary color of the
testsample. For example, the Nitrate-Nitrogentest produces apink color
proportionalto the nitrate concentrationin the sample (thegreater the nitrate
concentration,the darker thepink color). Agreen filter isused since a
pinkish-red solution absorbs mostly green light.
10

The 1200 Colorimeter has been specially calibrated to read test results directly in
parts per million (ppm) of the test factor. The sensitivity of the response has been
maximizedby using a specific, complementary light sourcefor each test.
REAGENT BLANK
Sometests will providegreater accuracy ifa reagent blankis determined, to
compensatefor any coloror turbidity resultingfrom thereagents themselves. A
reagent blank is performed by running the test procedure on 10 mL of
demineralized water. Use sample water to zero the meter. Insert the reagent blank
inthe colorimeter chamberand select READ. Note result of reagent blank.
Perform the tests on the unknown as described. Subtract results of reagent blank
fromall subsequenttest results.
COLORIMETER TUBES
Thehandling of the colorimeter tubesis of utmostimportance. Scratches,
fingerprintsand water droplets on the tube orinside the lightchamber can cause
straylight interference leadingto inaccurate results.It isimperative that the
tubes and light chamber be clean and dry. The glassware must be clean and
defect-free.Scratches and abrasionswill permanentlyaffect theaccuracyof the
readings. Tubescan beacid washedperiodically. Aftera tubehas beenfilled and
capped,it should be heldby the cap andthe outside surface shouldbe wiped with
a clean, lint-free absorbent cloth until it is dry and smudge-free. Handling the
tube only by the cap will avoid problems from fingerprints. Always set the clean
tubeaside on aclean surface thatwill notcontaminate the tube.
Variability in the geometry and quality of the glassware is the predominate cause
of variability in results. Orientation of the tube in the chamber will greatly affect
the test results. Toobtain the mostaccurate results,the tubesmustbe positioned
so that the index line on the tube is aligned with the arrow-shaped index mark t
molded into the housing in front of the light chamber. This will ensure that the
mostaccurate resultsare obtained.
11

SAMPLE DILUTION TECHNIQUES
& VOLUMETRIC MEASUREMENTS
If a test result using the 1200 Colorimeter gives anER2 (over range) message, the
sample must be diluted. Then the test should be repeated to obtain a reading
whichis inthe concentrationrange forthe test.(Note: Thisis nottrue for
colorimetric determination of pH.)
Example:
Measure 5 mL of the water sample into a graduated cylinder. Add demineralized
wateruntil thecylinder isfilled tothe 10 mLline. Thesample hasbeen diluted
by one-half, and the dilution factor is therefore 2. Perform the test procedure,
thenmultiply the resulting concentrationby 2 to obtainthe test result.
Thefollowing table gives quick referenceguidelines on dilutionsof various
proportions.All dilutions are based on a 10mL volume, soseveral dilutions will
requiresmall volumesof the watersample. Graduatedpipets shouldbe used forall
dilutions.
SizeofSample DeionizedWater to Bring Volume to 10 mL Multiplication Factor
10 mL 0 mL 1
5mL 5 mL 2
2.5mL 7.5 mL 4
1mL 9 mL 10
0.5mL 9.5 mL 20
Ifthe aboveglassware isnot available,dilutions canbe madewith thecolorimeter
tube.Fill the colorimetertube to the10 mL linewith the samplethen transfer it
toanother container. Add10 mL volumesof demineralizedwater to the
containerand mix. Transfer back 10 mL of the diluted sample to the colorimeter
tubeand follow thetest procedure. Continuediluting and testinguntil a reading,
whichis inthe concentration rangefor thetest, isobtained. Be sureto multiply
theconcentration found by the dilutionfactor (thenumber of total10 mL
volumes used).
Example:
10mL ofsample isdiluted withthree 10mL volumesof demineralizedwater; the
dilutionfactoris four.
12

INTERFERENCES
LaMottereagent systems aredesigned to minimizemost common interferences.
Each individual test discusses interferences unique to that test. Be aware of
possibleinterferences in thewater being tested.
Thereagent systems alsocontain buffersto adjust thewater sample to the ideal
pH for the reaction. It is possible that the buffer capacity of the water sample may
exceedthe buffer capacityof the reagentsystem and the ideal pHwill not be
obtained.If thisis suspected,measure the pH of areacted distilledwater reagent
blank using a pH meter. This is the ideal pH for the test. Measure the pH of a
reactedwater sample usingthe pHmeter.If thepH issignificantlydifferent from
the ideal value, the pH of the sample should be adjusted before testing.
Interferencesdue to highconcentration of thesubstance beingtested, can be
overcomebysample dilution(seepage 12).
STRAY LIGHT INTERFERENCE
Straylight interferencecan beminimized by alwayszeroing themeter and
readinga samplewith the lidclosed. Turbidimetricdeterminations(i.e. sulfate)
are most likely to exhibit a stray light interference. Colorimetric tests are less
likelyto havethis problemunless the samples are turbid.If sampleturbidity is
causing a stray light interference, filtration may be needed.
13

GENERAL OPERATING INFORMATION
OVERVIEW
The Model 1200 Colorimeter is a portable, microprocessor controlled, direct
reading colorimeter. The microprocessor enables factory programmed calibrations
to optimally match non-linear curves. The auto zero feature eliminates the need
to dial in the zero manually. A sealed keypad controls the operation. The large
displaypresents measurements inppm concentration andindicates low battery
warnings. The 1200 will turn off automatically after 5 minutes to prolong battery
life.This will notaffect the usercalibration and themeter will nothave to be
re-zeroed. The calibration and the last zero reading will be stored in memory.
The 1200 is supplied with a 9 volt alkaline battery. An optional AC power
adapter is available.
A RS-232 serial port on the back of the meter allows an interface of the
colorimeter with a computer for real time data acquisition and data storage using
thePC. This portalso allows aninterface with aRS-232 serial printer.
14

15

THE KEYPAD and DISPLAY
16

TESTING TIPS
17

CALIBRATION PROCEDURE
The 1200 has been pre-calibratede. Recalibration of the 1200 by the user is not
required. However, a procedure to standardize the calibration (shown below)
should be performed to obtain the most accurate readings.
18

uThe 1200 can be calibrated with two prepared standards. The concentrations
of the standards should be chosen from the low and high ends of the range of
the meter. The low standard must be less than 5% of over range. To calibrate
the meter with two standards, follow steps 1-11 of the calibration procedure
for one reacted sample. Repeat steps 1-11 of the calibration procdure with
the second reacted standard.
uThe calibration procedure should be followed as often as required by
regulations and laws for compliance monitoring.
uTo reset the calibration to the factory calibration: with the meter off, hold
down the tand push READ. The meter will turn on and the calibration
will be reset.
19

ANALYSIS PROCEDURE
20