• DetermineproductqualitywithROTRONICAwproducts

• ROTRONICAwdevicesforlaboratoryandportablesystems

• SpecialUSBprobesfordirectPCconnection

• AwQuickfunctionprovidesaccurateAwreadings

withinafewminutes

• Laboratorybench-topindicatorreadsupto4probes

simultaneously

• Largechoiceofprobesfordifferentapplications

• Easytocalibrateandmaintain

FAST AND PRECISE WATER ACTIVITY MEASUREMENTS.INTRODUCING AIRCHIP DIGITAL TECHNOLOGY.

WATER ACTIVITY MEASUREMENT

WATER ACTIVITY

ROTRONIC offers a complete range of water activity products. Use any combination of probes to fit your application.

ROTRONIC products are freely combinable and can be perfectly adapted to your needs. The devices are accurate and

are characterized by their high efficiency, exchangeability, and ease of calibration.

BE PRECISE:ADVANTAGES AT A GLANCE.

What is water activity?Wateractivity,bydefinition,isthemeasurementofwater

vaporpressuregeneratedby the freeornon-chemically

bound water in foods and other products. The bound

waterandmoisturecontentcannotbemeasureddirectly

withthismethod.TheAwvalue(range:0.00...1.00aw)is

animportantindicatorfortheshelflifeoffoods,pharma-

ceuticalandcosmeticproductsanditstronglyinfluences

theoccurrenceandgrowthofmicroorganisms.

Water activity Contaminantaw=0.91…0.95 Manybacteriaaw=0.88 Manyyeastsaw=0.80 Manymildewsaw=0.75 Halophilebacteriaaw=0.70 Osmiophileyeastsaw=0.65 Xerophilemildew

WATER ACTIVITY

Why measure water activity?Thefreewaterinaproductinfluencesitsmicrobiological,chemicalandenzymaticstability.Thisisofgreatimportanceespeciallyforper-

ishableproductssuchasfoods,grains,seedsandparticularlyforpharmaceuticalpowdersandtablets.Ifthereistoomuchfreewater,the

foodisspoiled.Toolittlewatercanadverselyaffectproductproperties.

Thetableshowstypicalgrowththresholdsbelowwhichthespecifiedorganismcannot

reproduceandthereforespoiltheproduct.Thereforewateractivityhasasignificantim-

pactontheshelflifeofaproduct.

Themeasurementofwateractivityalsoprovidesusefulinformationaboutcharacteristics

suchascohesion,storability,agglomerationorflowpropertiesofpowdersandtabletsor

theadhesionofcoatings.

Aw Quick functionality for very fast and precise resultsRegularAwmeasurementtakesaboutanhourtodetermineexactAwvalue.TheROTRONICAwQuickfunctionallowsAwmeasurement

resultsin5minutesorless.Thefunctionisnearlyaspreciseastheregularmeasurementmethod.Itrequiresanenvironmentwithstable

temperaturesvariationswhichismostlygiveninlaboratoryandindoorapplications.Thebench-topunitHygroLabC1,thehandhelddevice

HP23-AW-AandthesoftwareHW4-P-QUICK-VxallincludetheAwQuickcapability.

Foradditionaltimesavingupto4probescanbeconnectedtotheHygroLabC1.Forapplicationswithalargeamountofmeasurementsup

to64USBprobescanbedirectlyconnectedtotheHW4softwarewhichalsoprovidestheAwQuickfunction.

AllmeasurementresultsaresavedinlogfileseitherdirectlyinthedeviceorviatheHW4softwareonthePC.

Software calibrationIt'sessentialthatinstrumentshaveregularcalibrationcheckstraceabletonationalstand-

ardsensuringoptimumperformanceatalltimes.HW4softwareprovidesconvenient,easy

tousecontrolofthecalibrationprocess,andifrequired,thesensoradjustmentsequence:

• Fullsoftwarecontrolofcalibrationoradjustmentsequenceandtiming

• Singleormultiplepointsadjustment/calibration

• Preciseadjustmentto0.001Aw(0.1%RH)and0.1K

• Automaticgenerationofadjustment,calibrationandconfigurationreports

• Pre-configuredtosuitROTRONICSCScertifiedhumiditystandards

• Userconfigurablecalibrationandadjustmentprocess

WATER ACTIVITY

What is equilibrium relative humidity?Equilibriumrelativehumidity(ERH)isthevalueofrelativehumidityintowhichahygroscopicproductcanbeplacedwherenonetexchangeof

moisturebetweentheproductandthesurroundingenvironmentcantakeplace.Itisexpressedonascaleof0…100%.ERHistypicallyusedinthe

paperandpharmaceuticalindustries,butcanbeappliedtoalmostanyproductthatissensitivetomoisture,orwherethepresenceofmoisture

canaffectproducthandling.

Aw or ERH?BothAwandERHareanexpressionoftheamountoffreewatervaporpresentonaproduct,bothatitssurfaceandwithinitsstructure,andare

practicallythesamemeasurementexpressedinaslightlydifferentway.Throughoutthisbrochurewewillrefertowateractivity,butthiscanbe

interchangedwithERH.Wherespecified,ROTRONICproductsoffertheusertheoptiontoselectdisplayunitsasAwor%RH.

What is water content?Watercontent,whenreferring toasolidmaterial, isanexpressionof thepercentageof thematerialsweightwhich iswater (both in liquidor

gaseousphase);usuallyreferredtoas‘percentmoisturecontent’.Thistermiswidelyusedinmanyareasofindustry.

Water activity or water content?There is frequently confusion between water activity and water content

measurements. In many industries, water content is used to control the

amountofwaterpresentinaproductforquantitativereasons.Forexample,

ifaproduct issoldbyweight,controlling itswatercontentmaybeuseful

in maintaining product quality, but can also impact on profitability (more

waterequalsmoreprofit).Wateractivity ismoresignificant forqualitative

considerations such as product stability, shelf life (e.g. microbiological &

enzymaticstability,aroma retention),handlingcharacteristics (e.g.agglo-

meration of powders), physical properties (e.g. dimensions of paper) and

chemicalstability(e.g.pharmaceuticals).Wateractivityandwatercontent

canberelatedbyagraphcalledaSorptionIsotherm(seediagram)soifthe

user has the ability to measure both parameters, the relationship can be

definedandeachparameterderivedfromtheother(interpolation).Inpractice,thesorptionisothermmaybeimpracticaltouse,because,notonly

doestherelationshipbetweenAwandmoisturecontentchangewithtemperatureofmeasurement,butalsoanyvariationsinthematerialcompo-

sitionhasamodifyingeffect.Thisisespeciallythecasewithproductsofnaturaloriginsuchasfoodandpaper.Theusershouldthereforedecide

whichparameterofmeasurementisbestsuitedtotheirproductsandprocesses.Forqualitycontrolpurposesmoisturecontentlimitsareeasily

convertedtowateractivitylimitsbyverysimplecomparativetests.Wateractivitymeasurementoffersanon-destructive,easy-to-usemeasurement

inawiderangeofconvenientconfigurationsforbothlaboratoryandon-siteuse.

WATER ACTIVITY

Order code HygroLab C1

Probeconnections 4xHC2stationprobeorHC2insertionprobe

Parametersshown Aw,%RH,°C,°F

AwQuickfunction IntegratedandviaHW4softwareHW4-P-QUICK-Vx(inshipmentincluded)

Calculations Allpsychrometriccalculationsavailableoruserdefinedcalculations

Probeadjustment Singleormultiplepointforrelativehumidity&temperature

Oneortwopointtemperature

Memory 4x500Awvalues(2,000Awvalues)

Measurementinterval 1s

Start-uptime 3s

Powersupply 8…16VDCwithACadapter

Interfaces EthernetandUSB

HW4compatible V3.1andhigher

Rangeofapplication -10…60°C(14…140°F)/0…1Aw/0…100%RH

LCD 3-linealphanumericwithtrendindicators

Clock Realtimeclockprovidesatimestampforeverymeasurement

Currentconsumption Max.120mA(12VDC,backlightON,4probesconnected,Ethernet)

IPprotectionclass IP21

CE/EMCconform EMC2008/108/EG

FDA/GAMP FDA21CFRpart11/GAMP5

Dimensions/Weight 225x170x70mm/1100g

Material Aluminum,ABS-757

HygroLab C1

Laboratory applicationROTRONICprovidesahigh-endlaboratorydevice–theHygroLabC1–for

wateractivitymeasurementswithuptofourprobes.Connectstation

probesandinsertionprobesformeasuringwateractivityincheese,meat,

tobacco,buildingmaterials,animalfeed,pharmaceuticalsproductsand

muchmore.

Validated softwareEasy-to-useandintuitive,thelaboratorygradeindicatorcanbeusedby

anyone.HW4runningonaPCprovidesremotemonitoringwithcharting

anddatarecordingfunctions.

Features• 4inputchannelsforHC2stationprobesorHC2insertionprobes

canbeconnectedformeasurementofwateractivity,relativehumidity

andtemperature

• AwQuickfunctionforfastmeasurementresults(typically4-5minutes)

• Audiblealarmtoindicatecompletedmeasurement

• Savesupto2,000datarecordswith%RH,°C/°F,dateandtime

PS-40

HC2-AW

WP-40

AW-KHS

WATER ACTIVITY

Order code HC2-AW

Probetype MeasurementprobewithUARTinterface

Connection ViaUART,1mcable

Forusewith HygroLabC1,HP23-AW-A

Accuracyat23°C±5K(73.4°F) ±0.008Aw/±0.8%RH/±0.1K

Temperaturedependence 0.001K/K,0.0002aw/K

Sensor HYGROMER®WA-1/Pt-100,1/3DINClassB

Calculations Deworfrostpoint

Longtermstability <1%RH/year

Powersupply Viadisplayinstruments

Rangeofapplication -40…85°C(-40…185°F)/0…100%RH

Filtertype Wiremeshfilterwith20…25μmporesize

Responsetimet63 <20s

Measurementinterval 1s

Start-uptime 1.5s

IPprotection IP20

CE/EMCconformity EMC2008/108/EG

FDA/GAMP FDA21CFRpart11/GAMP5

Dimensions/Weight Ø68x60mm/600g

Material Stainlesssteel,aluminum

Aw station probesThestationprobesaredesignedforusingwithHygroLabC1

orHygroPalmHP23-AW-A.Measurementofwateractivitywiththis

digitalprobeisprecise,fastandeasy.Theprobecanbecalibra-

tedwiththeHygroLabC1orviatheHW4software.Minimized

internalvolumeofthesensorchamberensuresfastequilibrium

withallproducts,andanallmetalconstructionensuresgood

temperaturestabilityduringmeasurements,withstainlesssteel

usedonallcriticalsurfaces.Sampleholders,samplecontainers

andasealingmechanismaredetailedinaccessories.

Typical accessoriesSampleholders: WP-14-S,WP-40,WP-40TH

Disposablesamplecontainer: PS-14(14mmdeep),PS-40(40mmdeep)

Note: Ordersamplecontainersseparately.

Sampleholderscanalsobeusedascalibrationdevice.

Typical accessories