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Ammattilaiselta
Ammattilaisille
Huomioi! FATTORE Vitale & Co.
ei
 toimi kuluttajamarkkinoilla.

Yritykseltä
Yrityksille

Huomioi! FATTORE Vitale & Co.
ei
 toimi kuluttajamarkkinoilla.

30
 
VUOTTA
1983 - 2013
 

 

 HUOMIOI! Palvelemme klo.: 11:00 - 17:00  perjantaisin 11:00 - 15:00

 

soita aina ½h ENNEN KUIN TULET  

  Osoitekartta

Postiosoite

Sähköposti

Lankapuhelin

 

Käsipuhelin

Faksi

Y-tunnus

Palveluajat

Kuunkierros 3 F
02210 Espoo

 

PL 59
02211 Espoo

 

 

          

     

09 803 94 84     0500 205 819
Soita aina ennekuin tulet

 

09 803 94 21

 

0532156-7

 

Tiedustelulomake
Takaisin etusivulle

 

Painoit
Veden aktiivisuus AW

FATTORE Vitale & Co.:ssa olemme veden aktiivisuuden mittausten asiantuntijana yli 30-vuoden kokemuksella: luennoitsijana, kouluttajana sekä aw-laitteiden käyttöopastajana.

Toimitiloissamme ovat myös ROTRONIC AG:n valtuuttama huolto-, korjaus- ja kalibrointilaboratorio

FATTORE Vitale & Co.


ROTRONIC
:n virallinen maahantuoja
vuodesta 1983!

HP23-AW-SET-40
A Trend-Setter in your Water-Activity application.

HP23-AW
- mukana kulkeva Aw-laboratorio
Erikoistarjous

The HP23-AW sets are the perfect solution for on-site measurements.

They are supplied in a tough, lightweight ABS carry case and include everything needed for measurement and calibration.

Highlights

  • Measures humidity and temperature (aw or %rh and °C/°F)

  • Calculates absolute humidity

  • Software-aided probe calibration / adjustment (one-point / multi-point)

  • Range of application 0…1 aw (0…100 %rh) / -10…60 °C

  • UART interface

  • Battery power monitor

  • Trend indication

    Ote katalogista


 


Veden Aktiivisuuden (Aw) mittausasema

Rotronic HygroPalm aw1

 


Lemmikkien ruuat, tärkeää että hekin syövät hyvin!


Elintarviketeollisuus – juusto


Elintarviketeollisuus –lihatuotteet


Puutarhatuotteet – siemenet – estettävä varastoinnin aikainen pilaantuminen



Lääketeollisuus – tabletit ja jauheet ERH


 


Paperin tuotanto, muokkaus,
varastointi ja painatus


Rakennemateriaalit


Tupakkateollisuus

 

Veden aktiivisuuden anturit

wpeA.jpg (4335 bytes)
 

AW-DIO veden aktiivisuuden mittausasema ja WA-14

 

wpeB.jpg (4530 bytes)
 

Tilauskoodi: AW-DIO

 

 

 

wpeC.jpg (2518 bytes)

AW-DIO

AW-DIO on veden aktiivisuuden mittausasema, joka mittaa koko alueelta 0…1 Aw (0…100%RH) ja jossa on digitaalinen ulostulo-signaali mittareille/näyttölaitteille kuten
HygroLab ja HygroPalm Aw.
Digitaalinen kalibrointi voidaan suorittaa näyttölaitteen avulla.

aw_station.jpg

wpe5.jpg (16636 bytes)

 

 

 

 

 

 

 

 

 

 

 

 

 

Vesiaktiivisuudenmittaus keskimäärin viidessä minuutissa!

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 AW1 telakointiasemalla
jossa liitäntä
AC1207-virtalähteelle

DockingStat_adapter_kl.jpg

Lisävarusteena telakointiasema akkujen lataamiseen tai virran syöttöön
t
elakointiasema
PD1
 virtalähde AC1207

ROTRONIC -anturit soveltuvat lähes kaikkiin sovelluksiin.
Anturit perustuvat digitaaliseen teknologiaan taaten korkeatasoisen käyttäytymisen ja helpon kalibroinnin.
Kaikissa veden aktiivisuuden mittausasemissa ja antureissa on vakiona lämpötilan mittaus.

Fuehler_Set.jpg

     
HygroClip HK25   


HygroClipSP05

Aseman mahdollisimman pienen mittauselintä ympäröivän tilan takia tasapainotila saavutetaan nopeasti kaikilla materiaaleilla.

Kokometallinen rakenne takaa parhaan mittauksen aikaisen  lämpötila-stabiliteetin.

Kaikilla kriittisillä pinnoilla käytetään ruostumatonta terästä.

 Näytekupeista ja -alustoista sekä sulkijamekanismeista saa lisätietoja
Rotronic-katalogeista tai soittamalla
FATTORE Vitale & Co.
:lle numeroon 09 803 94 84 tai 0400 205 819.
Probeschalen.jpg

AW-DIO on nykyään peruslaite veden aktiivisuuden mittauksiin näytekupista ja  
on saatavana myös "turbo"-versiona;

AWVC
-malli integroidulla kiertoilmapuhaltimella. AW-DIO soveltuu tuttujen mittausasemien
WA-14
, WA40, AS-ST ja WAO tilalle.
AW-DIO:n mittausalueet ovat: 0...100 %rh (0...1 aw), 5...50°C
AW-DIO on varustettu erityisellä Aw-mittauselimellä ja parannetulla mekaanisella suunnittelulla.

Lämpötilan kontrolli

Joillekin näytteille on erityisen tärkeää ylläpitää tarkka ja tasapainotettu lämpötila koko mittaustapahtuman ajan.
 
ROTRONIC Aw-mitta-antureissa on korkea terminen massa hidastamassa lämpötilavaihteluja mittauksen aikana.
 
Suurimpaan tarkkuuteen, tai kun laboratorion lämpötila vaihtelee, suosittelemme
ROTRONIC:n lämpötilan kontrollilaitteita.
 

HygroPalm AW1

HygroPalm AW1 on veden aktiivisuuden mittaamiseen suunniteltu kuljetettava laite.

Se sisältää monia kehittyneitä ominaisuuksia kuten
Aw Quick -toiminto, jonka avulla mittaustulos saadaan jo 4-6 minuutissa.

Juuri tämän takia laite sopii hyvin käyttäjille, joka tarvitsee veden aktiivisuuden arvot nopeasti tuotannon keskellä, tavaroiden vastaanotossa, tai varastoalueilla – tällöin kuljetettava mittalaite on paikallaan.

Tärkeimmät ominaisuudet:

Nopeutettu veden aktiivisuuden mittaus:

(
AwQuick toiminto): mahdollistaa useimmista materiaaleissa mittaustuloksen n. 5 minuutissa

• Täysi tasapainotilan mittaus (perustoiminto) automaattisella tasapaino-olosuhteiden tunnistuksella

• Yksi digitaalinen anturin sisääntulo

• Yhden tai monen pisteen digitaalinen kalibrointi suoraan näppäimistöltä

• Näyttöyksikkönä
Aw

Tilauskoodi:
HygroPalm_aw.jpg
HygroPalm AW1

 

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• Saatavissa kantosalkun sisältävänä settinä:
HygroPalm AW1-SET/14

HygroPalm AW-setit

Paikanpäällä mittaamiseen tai ensimmäisenä Aw-laitehankintana HygroPalm AW1-setit ovat erinomaisia valintoja.
Setteihin kuuluu kevyt mutta luja ABS- muovinen salkku sisältäen kaiken tarpeellisen
Aw-mittauksiin ja laitteen huoltamiseen.

Kahden HygroPalm AW1 -settien ero on näyteastian ja sen alustan koossa.
AW1-Set/14 sisältää WP14-alustan WP_14_S_kl.jpg 
ja
PS14-astiat sopien mm. tableteille, jauhoille, siemenille, jauhetuille mausteille, teelle jne.
AW1-Set/40 sisältää WP40-alustan  
ja
PS40
-astiat
isommille näytteille kuten  lemmikkiruuat, pähkinät, pavut jne.



WP-40/WP-14 sample holder
shown with
PS-14/PS-40 disposable sample cups

 

HygroPalm AW-setit

 

 

Kuvaus

AW1-Set/14

AW1-Set/40

 

HygroPalm AW1  

HygroPalm AW1  

Kädessä pidettävä mittari/näyttölaite

AW-DIO

AW-DIO

Mittausanturi näyterasian päälle

WP-14-S

WP-40

Metallinen näyterasian alusta

PS-14

PS-40

Läpinäkyvä 13/6 näyterasia

EA35-SCS

EA35-SCS

35%RH kalibrointistandardi

EA80-SCS

EA80-SCS

80%RH kalibrointistandardi

EA50-SCS

EA50-SCS

50%RH kalibrointistandardi

EA10-SCS

EA10-SCS

10%RH kalibrointistandardi

AC1119

AC1119

Salkku

AW-DIO-aseman mitat

wpe2.jpg (17368 bytes)
 

Veden aktiivisuus parhaimmillaan
mm. makeisista (esim. lakritsi ja suklaa)


WP-40TH sample holder with integrated water jacket for temperature control.

 


 

Water Activity Measurement

ROTRONIC offers fast and accurate instruments for the measurement of water activity of foods, seeds,  pharmaceuticals, cosmetics, etc.

Our unique technology also guarantees water activity measurement at the lowest possible purchase price.
 
We offer a choice of three water activity systems that all use the same high precision to ensure consistently precise results and full interchangeability between the quality control laboratory and production areas.

Our probes can measure not only product samples but also materials in bulk and can test product packaging.

 

HygroPalm AW1 Set

HygroLab-2-HW4 Set

HygroLab 3 Set


Portable system in a carrying case


PC based system

LAB2_back.jpg


Bench-top system no PC required

HygroLab_A.jpg

HygroPalm AW1
portable indicator (battery operated), one
Aw-DIO probe for the measurement of product samples, accessories and a carrying case.

  • Measures water activity in typically 5 minutes!

  • Wide choice of probes, suitable for different applications

  • Ideal for low budget laboratories and quality control in the production

  • Uses the same technology as our more advanced systems

  •  

 

 

 

HygroLab 2
bench-top indicator, one
Aw-DIO probe for the measurement of product samples, accessories and HW4 software on a CD.
Requires PC with Windows XP or Vista.

  • Measures water activity in typically 5 minutes!

  • Full featured water activity software with capture of end values

  • Measures up to 4 product samples simultaneously

  • Wide choice of probes, suitable for different applications


HygroLab 2 Set


 

 

HygroLab 3
bench-top indicator, one Aw-DIO probe for the measurement of product samples, accessories and HW4 software on a CD (use of HW4 is optional).

  • Measures water activity in typically 5 minutes!

  • Measures up to 4 product samples simultaneously

  • Wide choice of probes, suitable for different applications

  • Compatible with the HW4 software (capture of end values, graph, data logging, etc.)


HygroLab 3 Set

 

 

HygroPalm AW1 Set

Portable system
in a carrying case

HygroPalm AW1 portable indicator (battery operated), one Aw-DIO probe for the measurement of product samples, accessories and
a carrying case.

  • Measures water activity in typically 5 minutes

  • Wide choice of probes, suitable for different applications

  • Ideal for low budget laboratories and quality control in the production

  • Uses the same technology as our more advanced systems

 

Water Activity Instruments:
a comparison of two measuring techniques

Abstract  
A point by point comparison shows that there is no real advantage of instruments that use a chilled mirror over instruments that use a relative humidity sensor.

Water Activity  Measuring Techniques
Commercially available water activity instruments commonly use one of the following humidity measurement techniques:

  • Chilled mirror
     

  • Relative humidity sensor (%RH)

    Instruments that use a relative humidity sensor are typically less expensive than instruments that use a chilled mirror.
     
    Do instruments based on a chilled mirror offer such benefits that paying a higher price is justified?
     
    This question can be answered after considering the following facts:

    Speed of Measurement


    Water activity is defined under static conditions of equilibrium. Under such conditions, the partial pressure of water vapor at the surface of the product is equal to the partial pressure of water vapor in the immediate environment of the product.
     
    When placed in a sealed chamber, most products typically require at least 20 to 30 minutes to achieve full water vapor pressure equilibrium with the air volume inside the chamber.
     
    This assumes that the temperature of the product sample and the temperature of the air volume inside the chamber are the same from the beginning to the end of the process.

    Unless something is very wrong, the time that is required to reach equilibrium does not depend on the technique used to measure humidity in the air volume above the product sample.

    Based on the above, getting a valid water activity reading in only a few minutes generally requires the use of a mathematical algorithm to project the final result ahead of the time when actual equilibrium occurs.
     
    In this regard, there is absolutely no difference between the chilled mirror technique and the relative humidity sensor technique.

    Temperature Stability

    Temperature stability is an important factor when measuring water activity.

    When measuring the water activity of a product, any temperature imbalance or temperature instability can change the partial pressure of water vapor generated by the product sample.

    Any type of sensor used to measure water activity, chilled mirror or relative humidity, is affected by this.

    When temperature is not stable, measurements typically take longer and are inaccurate.

    The temperature of a product sample takes more than a few minutes to change from one value to another.

    Using a fast response instrument that features a temperature controlled sample holder makes sense only when each product sample is pre-conditioned to the temperature of measurement.

    Accuracy

    Instruments based on the chilled mirror technique typically claim an accuracy of ± 0.003 aw.

    Instruments based on a relative humidity sensor claim a more modest ± 0.015 aw accuracy.

    Is the chilled mirror technique inherently more accurate when applied to the measurement of water activity?

    Here are three facts to consider:

    # 1: A chilled mirror measures dew point as opposed to measuring water activity.
     
    Any instrument that uses a chilled mirror computes water activity from the value of both dew point and temperature.

    The resulting accuracy depends on the combination of the errors made on the measurement of both dew point and temperature.

    # 2: At room temperature, the water activity of many foods is within the range of 0.800 to 1.000 aw.
     
    Within this range, measuring water activity with an accuracy of ± 0.003 aw would require dew point to be measured with an accuracy of ± 0.05°C,  assuming  no error on the measurement of temperature.

    Top-of-the-line chilled mirror instruments such as those used by national laboratories do not claim better than ± 0.10°C accuracy.
     
    A chilled mirror water activity instrument that claims an accuracy of ± 0.003 aw, 
    effectively claims to be at least two times more accurate than the best laboratory chilled mirror instruments Is this to be believed?

    # 3: At room temperature and within the range of 0.800 to 1.000 aw, the ± 0.015 aw accuracy claimed by instruments based on a relative humidity sensor corresponds to a dew point accuracy of ± 0.15°C (similar to a good chilled mirror instrument).
     
    This makes sense because the conversion of both dew point and temperature into relative humidity is always less accurate at high humidity values than at low humidity values.

    Considering the above, it is reasonable to suggest that the accuracy specification of ± 0.003 aw published by some manufacturers of chilled mirror water activity instruments possibly refers to the repeatability (or precision) of the instrument rather than to its actual accuracy.

    This kind or repeatability is matched by instruments using a relative humidity sensor.

    Range of Measurement
     
    The ability of a chilled mirror instrument to measure low water activity values depends both on the power available to cool the mirror and on the evacuation of heat away from the mirror.

    Chilled mirror based water activity instruments are usually severely limited and should not be used to measure products that are below 0.20 .. 0.30 aw.

    By contrast, a value of 0.01 Aw can be measured without problems with an instrument that uses a relative humidity sensor.

    Maintenance
     

    Many products contain volatile additives and some products are in the form of a fine powder.
     
    Because the chilled mirror operates at condensation, there is the tendency to trap airborne contaminants on the mirror.

    Since deposits on the mirror clearly affect measurement accuracy, frequent mirror cleaning is required.
     

  • Water Activity: Definition & Applications

    Definitions

    The moisture content of a product can be defined as the percentage weight of water in relation to the dry weight of the product.

    Products in which moisture can be present can be classified in two categories: hygroscopic and non hygroscopic.
     
    Examples of hygroscopic materials are salts, vegetal fibers, most metal oxides, many polymers, etc.
     
    Examples of non hygroscopic products are metal powders, glass granules, etc.

    Regarding the moisture content of a product, we define static equilibrium as a set of conditions under which the  product does not exchange any moisture with its environment.

    Under conditions of static equilibrium, the moisture content of a hygroscopic product depends on the nature of the product and also on the two following factors:


    (a) the partial pressure of water vapor in the immediate environment of the product
    (b) the temperature of the product

    If the moisture content of a product is not dependent on both these factors, then the product is not hygroscopic.


    Hygroscopic products may absorb water in different ways: sorption with formation of a hydrate, binding by surface energy, diffusion of water molecules in the material structure, capillary condensation, formation of a solution, etc. Depending on the absorption process, water is bound to the product with more or less strength.

    Moisture content can include both an immobilized part (e.g. water of hydration) and an active part.


    Water activity Aw (or equilibrium relative humidity %ERH) measures the vapor pressure generated by the moisture present in a hygroscopic product.
     

    aw = p / ps  and  %ERH = 100 x Aw, where:

    p    : partial pressure of water vapor at the surface of the product
    ps  : saturation pressure, or the partial pressure of water vapor above pure water at the product temperature


    Water activity reflects the active part of moisture content or the part which, under normal circumstances, can be exchanged between the product and its environment.

    Water activity is defined under static conditions of equilibrium.
     
    Under such conditions, the partial pressure of water vapor (p) at the surface of the product is equal to the partial pressure of water vapor in the immediate environment of the product.

    Any exchange of moisture between the product and its environment is driven by a difference between these two partial pressures.

    Finally, water vapor can also be present in a gas or gas mixture.

    The relative humidity of a gas is defined as %RH = 100 x p/ps, where (p) is the partial pressure of the water vapor present in the gas mixture and (ps) is
    the saturation pressure, or the partial pressure of water vapor above pure water at the temperature of the gas.

    Aw and Temperature

    Both water activity (materials) and relative humidity (gases) are referred to the saturation pressure (ps) or partial pressure of water vapor above pure water:

    aw = p / ps

    %RH = 100 x p/ps

    The saturation pressure (ps) is strongly dependent on temperature.

    At normal room temperature, ps increases by about 6.2% for a 1°C increase in temperature.

    In an open environment that is not saturated with water vapor, the partial pressure of water vapor (p) does not change with temperature.

    In a closed environment, (p) changes proportionally to the °K temperature (°K temperature = °C temperature + 273.16).
     
    At normal room temperature, the change in (p) caused by a small change in temperature is practically negligible.

    Because (p) does not change with temperature while (ps) does, the relative humidity of a gas (%RH = 100 x p/ps) is strongly temperature dependent.

     

    At 95 %RH and room temperature, an increase of 1°C results in a relative humidity decrease of about 6 %RH.
     
    At 50%RH, the same temperature increase causes relative humidity to decrease by about 3 %RH.

    The water activity of most hygroscopic products is not as strongly dependent on temperature.

    At room conditions, research data typically shows that water activity varies only by roughly 0.0005 to 0.005 aw (0.05 to 0.5 %RH) when temperature changes by 1°C.

    This is explained by the fact that the partial pressure (p) at the surface of a hygroscopic product does vary with temperature.

     Above most hygroscopic products, the magnitude of the change in the partial pressure of water vapor (p) with temperature is similar (but not exactly equal) to the magnitude of the change of the saturation pressure (ps) above pure water.

    In summary, a change in temperature causes the partial pressure of water vapor above a hygroscopic product to change.
     
    At the same time, the partial pressure in the air above the product is practically unchanged.
     
    It follows that any change in the temperature of a hygroscopic product automatically causes the product to exchange moisture with the air (or gas) that surrounds it.

    Moisture is exchanged until the partial water vapor pressure at the surface of the product and in the air are equal. When measuring aw, it is important to keep temperature as constant as possible both at the product sample and in the air above it.

    Applications

    The active part of moisture content and, therefore, water activity, provide better information than the total moisture content regarding the micro-biological, chemical and enzymatic stability of perishable products such as foods and seeds.
     
    For similar reasons, water activity is equally relevant in the pharmaceutical industry where it provides useful information regarding the cohesion of tablets and pills, or the adherence of coatings.
     
    Water activity can be directly compared with the relative humidity of the ambient air to prevent dimensional changes in a product (paper, photographic film), to prevent hygroscopic powders (powdered sugar, salt) from caking or turning into a solid block, etc


    Water activity can be used with some products (mostly synthetic products) as a means of indirectly measuring the total moisture content.
    This requires developing sorption isotherms to this purpose.

    Sorption isotherms are graphs that provide the relationship between water activity and moisture content at constant temperature.

    For most natural products, repeatable sorption isotherms cannot be reliably developed and water activity should be regarded as separate from moisture content.

    Takaisin etusivulle