GB897938A - Improvements in or relating to temperature measuring indicating and/or controlling apparatus - Google Patents

Improvements in or relating to temperature measuring indicating and/or controlling apparatus

Info

Publication number
GB897938A
GB897938A GB293360A GB293360A GB897938A GB 897938 A GB897938 A GB 897938A GB 293360 A GB293360 A GB 293360A GB 293360 A GB293360 A GB 293360A GB 897938 A GB897938 A GB 897938A
Authority
GB
United Kingdom
Prior art keywords
meter
thermocouple
leads
rectifier
voltage
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
GB293360A
Inventor
Ian Watt Stevenson
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.)
Kelvin Hughes Ltd
Original Assignee
Kelvin Hughes 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 Kelvin Hughes Ltd filed Critical Kelvin Hughes Ltd
Priority to GB293360A priority Critical patent/GB897938A/en
Priority to FR849308A priority patent/FR1277564A/en
Publication of GB897938A publication Critical patent/GB897938A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
    • G05D23/22—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature the sensing element being a thermocouple
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
    • G01K7/02—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using thermoelectric elements, e.g. thermocouples
    • G01K7/026—Arrangements for signalling failure or disconnection of thermocouples

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Protection Of Static Devices (AREA)

Abstract

897,938. Electrical indicating systems. KELVIN & HUGHES Ltd. Dec. 30, 1960 [Jan. 27, 1960], No. 2933/60. Class 40 (1). A temperature indicating, measuring and/or controlling system and protection circuit comprises a thermocouple 1 (e.g. in a furnace) connected to a D.C. meter 2, a source 31 of alternating voltage in series with a resistor 33 across the meter leads, and a rectifier 32 having a certain threshold voltage below which it will not conduct also connected across the leads, whereby breakage of the thermocouple may be signalled. Resistor 33 is adjusted so that when thermocouple 1 is intact the voltage across rectifier 32, which is preferably a silicon diode, is below the threshold value. Meter 2 is preferably a moving coil instrument, the moment of inertia of the coil being sufficient to prevent A.C. from source 31 producing a deflection. If, however, the thermocouple breaks the increased forward voltage across the rectifier causes it to conduct, which results in meter 2 receiving a large D.C. signal, and leads to the operation of a safety switch or warning system.
GB293360A 1960-01-27 1960-01-27 Improvements in or relating to temperature measuring indicating and/or controlling apparatus Expired GB897938A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB293360A GB897938A (en) 1960-01-27 1960-01-27 Improvements in or relating to temperature measuring indicating and/or controlling apparatus
FR849308A FR1277564A (en) 1960-01-27 1961-01-30 Temperature measuring, indicating and regulating device and protection device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB293360A GB897938A (en) 1960-01-27 1960-01-27 Improvements in or relating to temperature measuring indicating and/or controlling apparatus

Publications (1)

Publication Number Publication Date
GB897938A true GB897938A (en) 1962-05-30

Family

ID=9748793

Family Applications (1)

Application Number Title Priority Date Filing Date
GB293360A Expired GB897938A (en) 1960-01-27 1960-01-27 Improvements in or relating to temperature measuring indicating and/or controlling apparatus

Country Status (1)

Country Link
GB (1) GB897938A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3468164A (en) * 1966-08-26 1969-09-23 Westinghouse Electric Corp Open thermocouple detection apparatus
US3617886A (en) * 1968-07-26 1971-11-02 Bailey Meter Co Transducer open-circuit failure detector
US3760265A (en) * 1972-05-16 1973-09-18 Honeywell Inc Open circuit detection apparatus for thermocouple circuits
US4088947A (en) * 1976-06-03 1978-05-09 Rca Corporation Electrical continuity test apparatus having a forward biased diode across the test terminals

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3468164A (en) * 1966-08-26 1969-09-23 Westinghouse Electric Corp Open thermocouple detection apparatus
US3617886A (en) * 1968-07-26 1971-11-02 Bailey Meter Co Transducer open-circuit failure detector
US3760265A (en) * 1972-05-16 1973-09-18 Honeywell Inc Open circuit detection apparatus for thermocouple circuits
US4088947A (en) * 1976-06-03 1978-05-09 Rca Corporation Electrical continuity test apparatus having a forward biased diode across the test terminals

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