GB1392708A - Determination of moisture content in hygroscopic material - Google Patents
Determination of moisture content in hygroscopic materialInfo
- Publication number
- GB1392708A GB1392708A GB3613171A GB3613171A GB1392708A GB 1392708 A GB1392708 A GB 1392708A GB 3613171 A GB3613171 A GB 3613171A GB 3613171 A GB3613171 A GB 3613171A GB 1392708 A GB1392708 A GB 1392708A
- Authority
- GB
- United Kingdom
- Prior art keywords
- moisture content
- standard
- mass
- sample
- deviation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/22—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
- G01N27/223—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/22—Measuring resistance of fluids
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
1392708 Measuring moisture content electrically WIRA 23 June 1972 [31 July 1971] 36131/71 Heading G1N The moisture deviation per unit of standard mass at standard moisture content, #W/Mo of a sample of fibrous material is determined electrically from the equation:- and M o is the standard mass, W o is its moisture content and C o the capacitance change it produces of a reference sample and #M, #W, #C are the corresponding deviations from the reference sample of the production or batch sample. A reference sample 4 of fibrous material (textile, tobacco, wood, powder) of standard mass, standard moisture content and standard capacitance change it effects is placed on base 3 between the plates 1 of a measuring capacitor which forms part of oscillator circuit 2. The potentiometers Py, Px are then set according to the characteristics of the reference sample and oscillators 2, 6 adjusted to have equal frequencies, a final adjustment of the apparatus being made until meter 14 reads the known moisture content deviation in relation to the standard mass. The reference sample is then replaced by a production sample which will result in the frequency of the measuring oscillator changing and the frequency difference detected by mixer 8 is representative of the capacitor changes due to deviation in moisture content, mass and temperature of the production sample from the reference sample. To compensate for the deviations in temperature the signal from mixer 8 is modified in signal rectifier 13 by a signal from amplifier 12 the input of which is connected to a temperature probe 1 linserted in the sample and which may be a resistance thermometer, thermistor or thermocouple. After multiplying by the factor Px in potentiometer Px the signal is added to a signal representative of the total mass deviation per unit of standard mass at standard moisture content multiplied by the factor Py in potentiometer Py to give a reading on meter 14 representative of the percentage mass deviation in moisture content per unit of standard mass and since the latter is known the total moisture content deviation can be obtained. The mass deviation signal is obtained from a strain gauge 10 rigidly connected to base 3 and amplifier 9, the D.C. output of which is indicated by meter 15. Instead of having two oscillators only one is used which is provided with an adjustable capacitor to nullify the effect of the production sample. Alternatively capacitors 1, 5 may be connected in a bridge circuit.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB3613171A GB1392708A (en) | 1971-07-31 | 1971-07-31 | Determination of moisture content in hygroscopic material |
| AU44885/72A AU465118B2 (en) | 1971-07-31 | 1972-07-24 | Determination of moisture content in hygroscopic material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB3613171A GB1392708A (en) | 1971-07-31 | 1971-07-31 | Determination of moisture content in hygroscopic material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1392708A true GB1392708A (en) | 1975-04-30 |
Family
ID=10385292
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB3613171A Expired GB1392708A (en) | 1971-07-31 | 1971-07-31 | Determination of moisture content in hygroscopic material |
Country Status (2)
| Country | Link |
|---|---|
| AU (1) | AU465118B2 (en) |
| GB (1) | GB1392708A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6420882B1 (en) | 1997-04-08 | 2002-07-16 | Sentech Ag | Apparatus for capacitive electrical detection |
| EP1980844A1 (en) * | 2007-04-12 | 2008-10-15 | Manneschi, M. Alessandro | Analysing the composition of the content of a container by measuring the complex dielectric properties at plural frequences selected from the range of several Hz to plural Ghz and by measuring additionally at least one further physical quantity like the mass of the container with its content |
| MD3713G2 (en) * | 2008-05-19 | 2009-04-30 | Институт Химии Академии Наук Молдовы | Method for determining the normal water equilibrium variation domain |
-
1971
- 1971-07-31 GB GB3613171A patent/GB1392708A/en not_active Expired
-
1972
- 1972-07-24 AU AU44885/72A patent/AU465118B2/en not_active Expired
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6420882B1 (en) | 1997-04-08 | 2002-07-16 | Sentech Ag | Apparatus for capacitive electrical detection |
| EP1980844A1 (en) * | 2007-04-12 | 2008-10-15 | Manneschi, M. Alessandro | Analysing the composition of the content of a container by measuring the complex dielectric properties at plural frequences selected from the range of several Hz to plural Ghz and by measuring additionally at least one further physical quantity like the mass of the container with its content |
| FR2914998A1 (en) * | 2007-04-12 | 2008-10-17 | Alessandro Manneschi | DEVICE FOR ANALYZING THE COMPOSITION OF THE CONTENT OF A CONTAINER COMPRISING MEANS FOR OBTAINING AT LEAST ONE ADDITIONAL PHYSICAL DATA RELATING TO THE CONTAINER |
| US8030948B2 (en) | 2007-04-12 | 2011-10-04 | Manneschi Alessandro M | Device for analyzing the composition of the contents of a container comprising means for obtaining at least one additional physical datum relating to the container |
| MD3713G2 (en) * | 2008-05-19 | 2009-04-30 | Институт Химии Академии Наук Молдовы | Method for determining the normal water equilibrium variation domain |
Also Published As
| Publication number | Publication date |
|---|---|
| AU4488572A (en) | 1974-02-07 |
| AU465118B2 (en) | 1975-09-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PLNP | Patent lapsed through nonpayment of renewal fees |