GB1021570A - Apparatus for detecting heat protected against false actuation - Google Patents

Apparatus for detecting heat protected against false actuation

Info

Publication number
GB1021570A
GB1021570A GB3029864A GB3029864A GB1021570A GB 1021570 A GB1021570 A GB 1021570A GB 3029864 A GB3029864 A GB 3029864A GB 3029864 A GB3029864 A GB 3029864A GB 1021570 A GB1021570 A GB 1021570A
Authority
GB
United Kingdom
Prior art keywords
detector
abnormal
temperature
protected against
ohms
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
GB3029864A
Inventor
Roger Bennett Jones
Edgar John Schmidt
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.)
Specialties Development Corp
Original Assignee
Specialties Development Corp
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 Specialties Development Corp filed Critical Specialties Development Corp
Priority to GB3029864A priority Critical patent/GB1021570A/en
Publication of GB1021570A publication Critical patent/GB1021570A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
    • G08B21/18—Status alarms
    • G08B21/182—Level alarms, e.g. alarms responsive to variables exceeding a threshold

Landscapes

  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Fire-Detection Mechanisms (AREA)

Abstract

1,021,570. Temperature alarms. SPECIALTIES DEVELOPMENT CORPORATION. July 31, 1964, No. 30298/64. Heading G4N. [Also in Divisions H2 and H3] In a temperature alarm of the type in which an abnormal temperature varies the resistance of a detector element, false alarms due to moisture across the electrodes of the detector element are obviated by ensuring that the voltage across the element, when the abnormal resistance value is approached, is less than about 1À2 V. As described, resistors 40, 42, 45 and a detector cable 19<SP>1</SP> form a bridge. As the abnormal temperature is approached transistor 46 is cut off switching on transistor 54 to operate alarm relay 60. The supply 41 is 10 V., resistor 40 is 10,000 ohms and detector 191 about 700 ohms in the abnormal condition, giving a potential of about 0À7 voltas across the detector. It is stated that potentials of this order cause the moisture to polarize and thus make the leakage resistance Rs high.
GB3029864A 1964-07-31 1964-07-31 Apparatus for detecting heat protected against false actuation Expired GB1021570A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3029864A GB1021570A (en) 1964-07-31 1964-07-31 Apparatus for detecting heat protected against false actuation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3029864A GB1021570A (en) 1964-07-31 1964-07-31 Apparatus for detecting heat protected against false actuation

Publications (1)

Publication Number Publication Date
GB1021570A true GB1021570A (en) 1966-03-02

Family

ID=10305427

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3029864A Expired GB1021570A (en) 1964-07-31 1964-07-31 Apparatus for detecting heat protected against false actuation

Country Status (1)

Country Link
GB (1) GB1021570A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2464465A1 (en) * 1979-08-29 1981-03-06 Loher Gmbh TEMPERATURE CONTROL DEVICE

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2464465A1 (en) * 1979-08-29 1981-03-06 Loher Gmbh TEMPERATURE CONTROL DEVICE

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