CA2107519A1 - Communication system and method - Google Patents

Communication system and method

Info

Publication number
CA2107519A1
CA2107519A1 CA002107519A CA2107519A CA2107519A1 CA 2107519 A1 CA2107519 A1 CA 2107519A1 CA 002107519 A CA002107519 A CA 002107519A CA 2107519 A CA2107519 A CA 2107519A CA 2107519 A1 CA2107519 A1 CA 2107519A1
Authority
CA
Canada
Prior art keywords
circuit
novel
variable
signals
control
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.)
Granted
Application number
CA002107519A
Other languages
French (fr)
Other versions
CA2107519C (en
Inventor
Stephen George Seberger
Bruce Frederick Grumstrup
George Wayne Gassman
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.)
Fisher Controls International LLC
Original Assignee
Stephen George Seberger
Bruce Frederick Grumstrup
George Wayne Gassman
Fisher Controls International, Inc.
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 Stephen George Seberger, Bruce Frederick Grumstrup, George Wayne Gassman, Fisher Controls International, Inc. filed Critical Stephen George Seberger
Publication of CA2107519A1 publication Critical patent/CA2107519A1/en
Application granted granted Critical
Publication of CA2107519C publication Critical patent/CA2107519C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
    • G08C19/00—Electric signal transmission systems
    • G08C19/02—Electric signal transmission systems in which the signal transmitted is magnitude of current or voltage
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7758—Pilot or servo controlled
    • Y10T137/7761—Electrically actuated valve

Abstract

The present invention relates to a circuit which is connected to a two-conductor control system for a variable analog DC input and that also enables bidirectional digital communication along the two conductors for diagnostic operations of a transducer. The novel circuit includes a switch circuit that has a first position that provided the ability to accept both the variable DC analog signals and the bidirectional digital communication signals by presenting a first impedance for the DC signals and a second switch position for providing a second substantially higher impedance while using the same two-conductor system. The novel invention also includes an auxiliary analog input signal to the circuit which allows further control as a current feedback to a control algorithm in a microcontroller. An auxiliary process transmitter can sense pressure, temperature, flow or some other process related variable and couple it to the circuit for control of the transducers. Finally, the novel invention includes a novel voltage regulator and a capacitive voltage supply for utilizing the voltage on the two conductors from the controller to also power the device.
CA 2107519 1992-10-05 1993-10-01 Communication system and method Expired - Lifetime CA2107519C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US95704792A 1992-10-05 1992-10-05
US957,047 1992-10-05

Publications (2)

Publication Number Publication Date
CA2107519A1 true CA2107519A1 (en) 1994-04-06
CA2107519C CA2107519C (en) 2002-04-09

Family

ID=25499005

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 2107519 Expired - Lifetime CA2107519C (en) 1992-10-05 1993-10-01 Communication system and method

Country Status (6)

Country Link
US (2) US5451923A (en)
EP (1) EP0591926B1 (en)
JP (1) JP3421401B2 (en)
CA (1) CA2107519C (en)
DE (1) DE69327562T2 (en)
MX (1) MX9306152A (en)

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Also Published As

Publication number Publication date
JPH06244825A (en) 1994-09-02
EP0591926A3 (en) 1995-03-01
DE69327562D1 (en) 2000-02-17
US5684451A (en) 1997-11-04
MX9306152A (en) 1994-05-31
US5451923A (en) 1995-09-19
DE69327562T2 (en) 2000-06-29
EP0591926A2 (en) 1994-04-13
JP3421401B2 (en) 2003-06-30
EP0591926B1 (en) 2000-01-12
CA2107519C (en) 2002-04-09

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