GB770466A - Improvements in and relating to electric motor protection - Google Patents

Improvements in and relating to electric motor protection

Info

Publication number
GB770466A
GB770466A GB2346354A GB2346354A GB770466A GB 770466 A GB770466 A GB 770466A GB 2346354 A GB2346354 A GB 2346354A GB 2346354 A GB2346354 A GB 2346354A GB 770466 A GB770466 A GB 770466A
Authority
GB
United Kingdom
Prior art keywords
networks
network
relay
fuses
relating
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
GB2346354A
Inventor
Roy Newell Benns
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.)
British Thomson Houston Co Ltd
Original Assignee
British Thomson Houston 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 British Thomson Houston Co Ltd filed Critical British Thomson Houston Co Ltd
Priority to GB2346354A priority Critical patent/GB770466A/en
Publication of GB770466A publication Critical patent/GB770466A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/26—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
    • H02H3/28—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at two spaced portions of a single system, e.g. at opposite ends of one line, at input and output of apparatus
    • H02H3/286—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at two spaced portions of a single system, e.g. at opposite ends of one line, at input and output of apparatus involving comparison of similar homopolar quantities

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

770,466. Protective cut-out systems. BRITISH THOMSON-HOUSTON CO., Ltd. July 29, 1955 [Aug. 12, 1954], No. 23463/54. Class 38(5) To protect a polyphase motor 1 against single phasing should one of the fuses 5...7 blow, resistance network N<SP>1</SP>, N<SP>2</SP> is connected on each side of the fuses and a relay 15 is connected between normally equipotential points 0<SP>1</SP>, 0<SP>2</SP> of the networks. The relay 15 may be of an electronic kind and control the energisation of the trip coil 21 of a circuit-breaker 8, or an indicating or alarm circuit. Short-circuiting switches 30, .31 in conjunction with auxiliary resistances may be provided for unbalancing either of the networks to check the operation of the system. If a group of motors is supplied from a common source, each motor may be provided with a network and a single comparison network is connected to the supply source, a common relay being connected between the equipotential point of the comparison network and a conductor which is connected through a test. switch and rectifier to the respective point of each of the separate networks. According to the Provisional Specification the networks may comprise resistance, inductances or capacitances or combinations thereof.
GB2346354A 1954-08-12 1954-08-12 Improvements in and relating to electric motor protection Expired GB770466A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2346354A GB770466A (en) 1954-08-12 1954-08-12 Improvements in and relating to electric motor protection

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2346354A GB770466A (en) 1954-08-12 1954-08-12 Improvements in and relating to electric motor protection

Publications (1)

Publication Number Publication Date
GB770466A true GB770466A (en) 1957-03-20

Family

ID=10196028

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2346354A Expired GB770466A (en) 1954-08-12 1954-08-12 Improvements in and relating to electric motor protection

Country Status (1)

Country Link
GB (1) GB770466A (en)

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