GB557077A - Improvements in or relating to electric signalling systems - Google Patents

Improvements in or relating to electric signalling systems

Info

Publication number
GB557077A
GB557077A GB5819/42A GB581942A GB557077A GB 557077 A GB557077 A GB 557077A GB 5819/42 A GB5819/42 A GB 5819/42A GB 581942 A GB581942 A GB 581942A GB 557077 A GB557077 A GB 557077A
Authority
GB
United Kingdom
Prior art keywords
loop
contacts
relay
closed
relays
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
GB5819/42A
Other languages
English (en)
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB557077A publication Critical patent/GB557077A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/06—Electric actuation of the alarm, e.g. using a thermally-operated switch
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/02—Monitoring continuously signalling or alarm systems
    • G08B29/06—Monitoring of the line circuits, e.g. signalling of line faults

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Alarm Systems (AREA)
  • Fire Alarms (AREA)
  • Interface Circuits In Exchanges (AREA)
GB5819/42A 1942-04-30 1942-04-30 Improvements in or relating to electric signalling systems Expired GB557077A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB254967X 1942-04-30
GB110942X 1942-09-11

Publications (1)

Publication Number Publication Date
GB557077A true GB557077A (en) 1943-11-03

Family

ID=26248048

Family Applications (2)

Application Number Title Priority Date Filing Date
GB5819/42A Expired GB557077A (en) 1942-04-30 1942-04-30 Improvements in or relating to electric signalling systems
GB12842/42A Expired GB560007A (en) 1942-04-30 1942-09-11 Improvements in or relating to electric signalling systems

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB12842/42A Expired GB560007A (en) 1942-04-30 1942-09-11 Improvements in or relating to electric signalling systems

Country Status (5)

Country Link
US (1) US2367258A (enrdf_load_stackoverflow)
BE (1) BE468184A (enrdf_load_stackoverflow)
CH (1) CH254967A (enrdf_load_stackoverflow)
FR (1) FR932231A (enrdf_load_stackoverflow)
GB (2) GB557077A (enrdf_load_stackoverflow)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE469337A (enrdf_load_stackoverflow) * 1945-10-19

Also Published As

Publication number Publication date
US2367258A (en) 1945-01-16
FR932231A (fr) 1948-03-16
BE468184A (enrdf_load_stackoverflow)
GB560007A (en) 1944-03-15
CH254967A (de) 1948-05-31

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