GB1455121A - Moisture meters - Google Patents

Moisture meters

Info

Publication number
GB1455121A
GB1455121A GB46573A GB46573A GB1455121A GB 1455121 A GB1455121 A GB 1455121A GB 46573 A GB46573 A GB 46573A GB 46573 A GB46573 A GB 46573A GB 1455121 A GB1455121 A GB 1455121A
Authority
GB
United Kingdom
Prior art keywords
electrode
sample
capacitors
electrodes
jan
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
Application number
GB46573A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Probe Engineering Co Ltd
Original Assignee
Probe Engineering Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Probe Engineering Co Ltd filed Critical Probe Engineering Co Ltd
Priority to GB46573A priority Critical patent/GB1455121A/en
Publication of GB1455121A publication Critical patent/GB1455121A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • 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

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

1455121 Electro-physical measurementmoisture PROBE ENG CO Ltd 2 Jan 1974 [4 Jan 1973] 465/73 Heading G1N A capacitance type moisture meter for e.g. grain or hay, comprises sample and reference capacitors in which the electrode spacings in each are simultaneously variable under a common control (to compress the material in the sample capacitor so that no air voids are left) and means for comparing and indicating the ratio of the capacitances. As described and illustrated schematically in Fig. 2, the sample cell comprises a disc electrode 3 and a coaxial piston-electrode 13. The reference cell comprises the surrounding cylindrical electrode 14 and annular electrode 4. Constructional details are given in Fig. 1 (not shown). The electrodes 13, 14 are mounted in a housing adapted to screw down towards the lower electrodes 3, 4 and an earthed guard electrode (7) is mounted in the base between the electrodes 3, 4. CIRCUIT FIG. 3 The reference and sample capacitors Co, Gi, are connected in the feedback path and input respectively to serially arranged operational amplifiers with fixed capacitors Ca, Cb as shown. With V in constant (amplitude and frequency) V out α Kr (the permittivity of the sample); if V in is varied to maintain V out constant, V in α 1/Kr alternatively the ratio V in /V out may be used. In a modified circuit Fig. 4 (not shown) a phasesensitive output detector is used to sense either the capacitive or resistive components of the output.
GB46573A 1973-01-04 1973-01-04 Moisture meters Expired GB1455121A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB46573A GB1455121A (en) 1973-01-04 1973-01-04 Moisture meters

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB46573A GB1455121A (en) 1973-01-04 1973-01-04 Moisture meters

Publications (1)

Publication Number Publication Date
GB1455121A true GB1455121A (en) 1976-11-10

Family

ID=9704834

Family Applications (1)

Application Number Title Priority Date Filing Date
GB46573A Expired GB1455121A (en) 1973-01-04 1973-01-04 Moisture meters

Country Status (1)

Country Link
GB (1) GB1455121A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0303356A2 (en) * 1987-08-14 1989-02-15 Impact Systems, Inc. Scanning combination thickness and moisture gauge for moving sheet material

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0303356A2 (en) * 1987-08-14 1989-02-15 Impact Systems, Inc. Scanning combination thickness and moisture gauge for moving sheet material
EP0303356A3 (en) * 1987-08-14 1989-11-29 Impact Systems, Inc. Scanning combination thickness and moisture gauge for moving sheet material

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee